Last data update: Jun 24, 2024. (Total: 47078 publications since 2009)
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Query Trace: Jo H [original query] |
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HIV risk behaviour, viraemia, and transmission across HIV cascade stages including low-level viremia: Analysis of 14 cross-sectional population-based HIV Impact Assessment surveys in sub-Saharan Africa
Edun O , Okell L , Chun H , Bissek AZ , Ndongmo CB , Shang JD , Brou H , Ehui E , Ekra AK , Nuwagaba-Biribonwoha H , Dlamini SS , Ginindza C , Eshetu F , Misganie YG , Desta SL , Achia TNO , Aoko A , Jonnalagadda S , Wafula R , Asiimwe FM , Lecher S , Nkanaunena K , Nyangulu MK , Nyirenda R , Beukes A , Klemens JO , Taffa N , Abutu AA , Alagi M , Charurat ME , Dalhatu I , Aliyu G , Kamanzi C , Nyagatare C , Rwibasira GN , Jalloh MF , Maokola WM , Mgomella GS , Kirungi WL , Mwangi C , Nel JA , Minchella PA , Gonese G , Nasr MA , Bodika S , Mungai E , Patel HK , Sleeman K , Milligan K , Dirlikov E , Voetsch AC , Shiraishi RW , Imai-Eaton JW . PLOS Glob Public Health 2024 4 (4) e0003030 As antiretroviral treatment (ART) coverage for people living with HIV (PLHIV) increases, HIV programmes require up-to-date information about evolving HIV risk behaviour and transmission risk, including those with low-level viremia (LLV; >50 to ≤1000 copies/mL), to guide prevention priorities. We aimed to assess differences in sexual risk behaviours, distribution of viral load (VL) and proportion of transmission across PLHIV subgroups. We analysed data from Population-based HIV Impact Assessment surveys in 14 sub-Saharan African countries during 2015-2019. We estimated adjusted prevalence ratios (aPR) of self-reported HIV high-risk behaviour (multiple partners and condomless sex) across cascade stages via generalised estimation equations. We modelled the proportions of transmission from each subgroup using relative self-reported sexual risk, a Hill function for transmission rate by VL, and proportions within cascade stages from surveys and UNAIDS country estimates for 2010-2020. Compared to PLHIV with undetectable VL (≤50 copies/mL), undiagnosed PLHIV (aPR women: 1.28 [95% CI: 1.08-1.52]; men: 1.61 [1.33-1.95]) and men diagnosed but untreated (2.06 [1.52-2.78]) were more likely to self-report high-risk sex. High-risk behaviour was not significantly associated with LLV. Mean VL was similar among undiagnosed, diagnosed but untreated, and on ART but non-suppressed sub-groups. Across surveys, undiagnosed and diagnosed but untreated contributed most to transmission (40-91% and 1-41%, respectively), with less than 1% from those with LLV. Between 2010 and 2020, the proportion of transmission from individuals on ART but non-suppressed increased. In settings with high ART coverage, effective HIV testing, ART linkage, and retention remain priorities to reduce HIV transmission. Persons with LLV are an increasing share of PLHIV but their contribution to HIV transmission was small. Improving suppression among PLHIV on ART with VL ≥1000 copies/mL will become increasingly important. |
National Stop Transmission of Polio Program support for polio supplemental immunization activities in Nigeria 2012-2016: deployment of management support team
Edukugho AA , Waziri NE , Bolu O , Gidado SO , Okeke LA , Uba BV , Idris JM , Michael CA , Adegoke JO , Bammeke P , Adamu US , Nguku PM , Biya O , Ohuanbunwo CJ , Vertefeuille J , Damisa E , Wiesen E . Pan Afr Med J 12/28/2021 40 14 INTRODUCTION: to support polio eradication activities in Nigeria, in 2012 the National Polio Emergency Operation Center (NEOC) created the Management Support Teams (MST) to address gaps in the quality of supervision of polio vaccination teams. The National Stop Transmission of Polio (NSTOP) Program supported the polio eradication activities by deploying trained supervisors as part of the MST for polio and non-polio immunization campaigns. METHODS: trained MST members were deployed approximately 4 days before the start of the campaign to participate in pre-implementation activities and supervise vaccination teams during campaigns. Terms of reference (TOR) developed by NEOC was provided to MST members to guide their activities. Qualified MSTs that met pre-determined criteria were selected and deployed to the field to support pre, intra and post campaigns activities. RESULTS: a pool of over 400 MST personnel have been identified, trained, and repeatedly deployed from 2012 till 2016. The number of deployed MST personnel rose from 40 per campaign in October 2012 to 342 in May 2016. Of these, 270 (79%) MST personnel were deployed to 11 polio high-risk states of northern Nigeria, where campaigns are conducted between eight and ten times yearly as planned by NEOC. For measles campaigns, about 300 (75%) MST personnel were deployed for the one-off northern and southern campaigns in 2016. The results of clustered Lot Quality Assurance Sampling (LQAS) post-campaign vaccination coverage surveys, a measure of campaign quality, of which introduction into the polio program coincided with deployment of MSTs, showed improvement over time, from 10% (very poor quality) in February 2012 to about 90% (good quality) in December 2016. CONCLUSION: the deployment of MST personnel increased the number of trained supervisors in the field, frequency of supervisory visits and had a positive impact on the quality of polio campaigns. |
Factors predicting mortality in hospitalised HIV-negative children with lower-chest-wall indrawing pneumonia and implications for management
Gallagher KE , Awori JO , Knoll MD , Rhodes J , Higdon MM , Hammitt LL , Prosperi C , Baggett HC , Brooks WA , Fancourt N , Feikin DR , Howie SRC , Kotloff KL , Tapia MD , Levine OS , Madhi SA , Murdoch DR , O'Brien KL , Thea DM , Baillie VL , Ebruke BE , Kamau A , Moore DP , Mwananyanda L , Olutunde EO , Seidenberg P , Sow SO , Thamthitiwat S , Scott JAG . PLoS One 2024 19 (3) e0297159 INTRODUCTION: In 2012, the World Health Organization revised treatment guidelines for childhood pneumonia with lower chest wall indrawing (LCWI) but no 'danger signs', to recommend home-based treatment. We analysed data from children hospitalized with LCWI pneumonia in the Pneumonia Etiology Research for Child Health (PERCH) study to identify sub-groups with high odds of mortality, who might continue to benefit from hospital management but may not be admitted by staff implementing the 2012 guidelines. We compare the proportion of deaths identified using the criteria in the 2012 guidelines, and the proportion of deaths identified using an alternative set of criteria from our model. METHODS: PERCH enrolled a cohort of 2189 HIV-negative children aged 2-59 months who were admitted to hospital with LCWI pneumonia (without obvious cyanosis, inability to feed, vomiting, convulsions, lethargy or head nodding) between 2011-2014 in Kenya, Zambia, South Africa, Mali, The Gambia, Bangladesh, and Thailand. We analysed risk factors for mortality among these cases using predictive logistic regression. Malnutrition was defined as mid-upper-arm circumference <125mm or weight-for-age z-score <-2. RESULTS: Among 2189 cases, 76 (3·6%) died. Mortality was associated with oxygen saturation <92% (aOR 3·33, 1·99-5·99), HIV negative but exposed status (4·59, 1·81-11·7), moderate or severe malnutrition (6·85, 3·22-14·6) and younger age (infants compared to children 12-59 months old, OR 2·03, 95%CI 1·05-3·93). At least one of three risk factors: hypoxaemia, HIV exposure, or malnutrition identified 807 children in this population, 40% of LCWI pneumonia cases and identified 86% of the children who died in hospital (65/76). Risk factors identified using the 2012 WHO treatment guidelines identified 66% of the children who died in hospital (n = 50/76). CONCLUSIONS: Although it focuses on treatment failure in hospital, this study supports the proposal for better risk stratification of children with LCWI pneumonia. Those who have hypoxaemia, any malnutrition or those who were born to HIV positive mothers, experience poorer outcomes than other children with LCWI pneumonia. Consistent identification of these risk factors should be prioritised and children with at least one of these risk factors should not be managed in the community. |
2020 Ebola virus disease outbreak in Équateur Province, Democratic Republic of the Congo: a retrospective genomic characterisation
Kinganda-Lusamaki E , Whitmer S , Lokilo-Lofiko E , Amuri-Aziza A , Muyembe-Mawete F , Makangara-Cigolo JC , Makaya G , Mbuyi F , Whitesell A , Kallay R , Choi M , Pratt C , Mukadi-Bamuleka D , Kavunga-Membo H , Matondo-Kuamfumu M , Mambu-Mbika F , Ekila-Ifinji R , Shoemaker T , Stewart M , Eng J , Rajan A , Soke GN , Fonjungo PN , Otshudiema JO , Folefack GLT , Pukuta-Simbu E , Talundzic E , Shedroff E , Bokete JL , Legand A , Formenty P , Mores CN , Porzucek AJ , Tritsch SR , Kombe J , Tshapenda G , Mulangu F , Ayouba A , Delaporte E , Peeters M , Wiley MR , Montgomery JM , Klena JD , Muyembe-Tamfum JJ , Ahuka-Mundeke S , Mbala-Kingebeni P . Lancet Microbe 2024 ![]() ![]() ![]() BACKGROUND: The Democratic Republic of the Congo has had 15 Ebola virus disease (EVD) outbreaks, from 1976 to 2023. On June 1, 2020, the Democratic Republic of the Congo declared an outbreak of EVD in the western Équateur Province (11th outbreak), proximal to the 2018 Tumba and Bikoro outbreak and concurrent with an outbreak in the eastern Nord Kivu Province. In this Article, we assessed whether the 11th outbreak was genetically related to previous or concurrent EVD outbreaks and connected available epidemiological and genetic data to identify sources of possible zoonotic spillover, uncover additional unreported cases of nosocomial transmission, and provide a deeper investigation into the 11th outbreak. METHODS: We analysed epidemiological factors from the 11th EVD outbreak to identify patient characteristics, epidemiological links, and transmission modes to explore virus spread through space, time, and age groups in the Équateur Province, Democratic Republic of the Congo. Trained field investigators and health professionals recorded data on suspected, probable, and confirmed cases, including demographic characteristics, possible exposures, symptom onset and signs and symptoms, and potentially exposed contacts. We used blood samples from individuals who were live suspected cases and oral swabs from individuals who were deceased to diagnose EVD. We applied whole-genome sequencing of 87 available Ebola virus genomes (from 130 individuals with EVD between May 19 and Sept 16, 2020), phylogenetic divergence versus time, and Bayesian reconstruction of phylogenetic trees to calculate viral substitution rates and study viral evolution. We linked the available epidemiological and genetic datasets to conduct a genomic and epidemiological study of the 11th EVD outbreak. FINDINGS: Between May 19 and Sept 16, 2020, 130 EVD (119 confirmed and 11 probable) cases were reported across 13 Équateur Province health zones. The individual identified as the index case reported frequent consumption of bat meat, suggesting the outbreak started due to zoonotic spillover. Sequencing revealed two circulating Ebola virus variants associated with this outbreak-a Mbandaka variant associated with the majority (97%) of cases and a Tumba-like variant with similarity to the ninth EVD outbreak in 2018. The Tumba-like variant exhibited a reduced substitution rate, suggesting transmission from a previous survivor of EVD. INTERPRETATION: Integrating genetic and epidemiological data allowed for investigative fact-checking and verified patient-reported sources of possible zoonotic spillover. These results demonstrate that rapid genetic sequencing combined with epidemiological data can inform responders of the mechanisms of viral spread, uncover novel transmission modes, and provide a deeper understanding of the outbreak, which is ultimately needed for infection prevention and control during outbreaks. FUNDING: WHO and US Centers for Disease Control and Prevention. |
Child deaths caused by Klebsiella pneumoniae in sub-Saharan Africa and south Asia: a secondary analysis of Child Health and Mortality Prevention Surveillance (CHAMPS) data
Verani JR , Blau DM , Gurley ES , Akelo V , Assefa N , Baillie V , Bassat Q , Berhane M , Bunn J , Cossa ACA , El Arifeen S , Gunturu R , Hale M , Igunza A , Keita AM , Kenneh S , Kotloff KL , Kowuor D , Mabunda R , Madewell ZJ , Madhi S , Madrid L , Mahtab S , Miguel J , Murila FV , Ogbuanu IU , Ojulong J , Onyango D , Oundo JO , Scott JAG , Sow S , Tapia M , Traore CB , Velaphi S , Whitney CG , Mandomando I , Breiman RF . Lancet Microbe 2024 BACKGROUND: Klebsiella pneumoniae is an important cause of nosocomial and community-acquired pneumonia and sepsis in children, and antibiotic-resistant K pneumoniae is a growing public health threat. We aimed to characterise child mortality associated with this pathogen in seven high-mortality settings. METHODS: We analysed Child Health and Mortality Prevention Surveillance (CHAMPS) data on the causes of deaths in children younger than 5 years and stillbirths in sites located in seven countries across sub-Saharan Africa (Ethiopia, Kenya, Mali, Mozambique, Sierra Leone, and South Africa) and south Asia (Bangladesh) from Dec 9, 2016, to Dec 31, 2021. CHAMPS sites conduct active surveillance for deaths in catchment populations and following reporting of an eligible death or stillbirth seek consent for minimally invasive tissue sampling followed by extensive aetiological testing (microbiological, molecular, and pathological); cases are reviewed by expert panels to assign immediate, intermediate, and underlying causes of death. We reported on susceptibility to antibiotics for which at least 30 isolates had been tested, and excluded data on antibiotics for which susceptibility testing is not recommended for Klebsiella spp due to lack of clinical activity (eg, penicillin and ampicillin). FINDINGS: Among 2352 child deaths with cause of death assigned, 497 (21%, 95% CI 20-23) had K pneumoniae in the causal chain of death; 100 (20%, 17-24) had K pneumoniae as the underlying cause. The frequency of K pneumoniae in the causal chain was highest in children aged 1-11 months (30%, 95% CI 26-34; 144 of 485 deaths) and 12-23 months (28%, 22-34; 63 of 225 deaths); frequency by site ranged from 6% (95% CI 3-11; 11 of 184 deaths) in Bangladesh to 52% (44-61; 71 of 136 deaths) in Ethiopia. K pneumoniae was in the causal chain for 450 (22%, 95% CI 20-24) of 2023 deaths that occurred in health facilities and 47 (14%, 11-19) of 329 deaths in the community. The most common clinical syndromes among deaths with K pneumoniae in the causal chain were sepsis (44%, 95% CI 40-49; 221 of 2352 deaths), sepsis in conjunction with pneumonia (19%, 16-23; 94 of 2352 deaths), and pneumonia (16%, 13-20; 80 of 2352 deaths). Among K pneumoniae isolates tested, 121 (84%) of 144 were resistant to ceftriaxone and 80 (75%) of 106 to gentamicin. INTERPRETATION: K pneumoniae substantially contributed to deaths in the first 2 years of life across multiple high-mortality settings, and resistance to antibiotics used for sepsis treatment was common. Improved strategies are needed to rapidly identify and appropriately treat children who might be infected with this pathogen. These data suggest a potential impact of developing and using effective K pneumoniae vaccines in reducing neonatal, infant, and child deaths globally. FUNDING: Bill & Melinda Gates Foundation. |
Public health data applications using the CDC Tracking Network: Augmenting environmental hazard information with lower-latency NASA data
Amos HM , Skaff NK , Uz SS , Policelli FS , Slayback D , Macorps E , Jo MJ , Patel K , Keller CA , Abue P , Buchard V , Werner AK . Geohealth 2023 7 (12) e2023GH000971 Exposure to environmental hazards is an important determinant of health, and the frequency and severity of exposures is expected to be impacted by climate change. Through a partnership with the U.S. National Aeronautics and Space Administration, the U.S. Centers for Disease Control and Prevention's National Environmental Public Health Tracking Network is integrating timely observations and model data of priority environmental hazards into its publicly accessible Data Explorer (https://ephtracking.cdc.gov/DataExplorer/). Newly integrated data sets over the contiguous U.S. (CONUS) include: daily 5-day forecasts of air quality based on the Goddard Earth Observing System Composition Forecast, daily historical (1980-present) concentrations of speciated PM(2.5) based on the modern era retrospective analysis for research and applications, version 2, and Moderate Resolution Imaging Spectroradiometer (MODIS) daily near real-time maps of flooding (MCDWD). Data integrated into the CDC Tracking Network are broadly intended to improve community health through action by informing both research and early warning activities, including (a) describing temporal and spatial trends in disease and potential environmental exposures, (b) identifying populations most affected, (c) generating hypotheses about associations between health and environmental exposures, and (d) developing, guiding, and assessing environmental public health policies and interventions aimed at reducing or eliminating health outcomes associated with environmental factors. |
Genomic surveillance of SARS-CoV-2 reveals highest severity and mortality of delta over other variants: evidence from Cameroon
Fokam J , Essomba RG , Njouom R , Okomo MA , Eyangoh S , Godwe C , Tegomoh B , Otshudiema JO , Nwobegahay J , Ndip L , Akenji B , Takou D , Moctar MMM , Mbah CK , Ndze VN , Maidadi-Foudi M , Kouanfack C , Tonmeu S , Ngono D , Nkengasong J , Ndembi N , Bissek AZK , Mouangue C , Ndongo CB , Epée E , Mandeng N , Kamso Belinga S , Ayouba A , Fernandez N , Tongo M , Colizzi V , Halle-Ekane GE , Perno CF , Ndjolo A , Ndongmo CB , Shang J , Esso L , de-Tulio O , Diagne MM , Boum Y 2nd , Mballa GAE , Njock LR . Sci Rep 2023 13 (1) 21654 ![]() ![]() While the SARS-CoV-2 dynamic has been described globally, there is a lack of data from Sub-Saharan Africa. We herein report the dynamics of SARS-CoV-2 lineages from March 2020 to March 2022 in Cameroon. Of the 760 whole-genome sequences successfully generated by the national genomic surveillance network, 74% were viral sub-lineages of origin and non-variants of concern, 15% Delta, 6% Omicron, 3% Alpha and 2% Beta variants. The pandemic was driven by SARS-CoV-2 lineages of origin in wave 1 (16 weeks, 2.3% CFR), the Alpha and Beta variants in wave 2 (21 weeks, 1.6% CFR), Delta variants in wave 3 (11 weeks, 2.0% CFR), and omicron variants in wave 4 (8 weeks, 0.73% CFR), with a declining trend over time (p = 0.01208). Even though SARS-CoV-2 heterogeneity did not seemingly contribute to the breadth of transmission, the viral lineages of origin and especially the Delta variants appeared as drivers of COVID-19 severity in Cameroon. |
Recommendations on data sharing in HIV drug resistance research
Inzaule SC , Siedner MJ , Little SJ , Avila-Rios S , Ayitewala A , Bosch RJ , Calvez V , Ceccherini-Silberstein F , Charpentier C , Descamps D , Eshleman SH , Fokam J , Frenkel LM , Gupta RK , Ioannidis JPA , Kaleebu P , Kantor R , Kassaye SG , Kosakovsky Pond SL , Kouamou V , Kouyos RD , Kuritzkes DR , Lessells R , Marcelin AG , Mbuagbaw L , Minalga B , Ndembi N , Neher RA , Paredes R , Pillay D , Raizes EG , Rhee SY , Richman DD , Ruxrungtham K , Sabeti PC , Schapiro JM , Sirivichayakul S , Steegen K , Sugiura W , van Zyl GU , Vandamme AM , Wensing AMJ , Wertheim JO , Gunthard HF , Jordan MR , Shafer RW . PLoS Med 2023 20 (9) e1004293 Author summary • Human immunodeficiency virus (HIV) drug resistance has implications for antiretroviral treatment strategies and for containing the HIV pandemic because the development of HIV drug resistance leads to the requirement for antiretroviral drugs that may be less effective, less well-tolerated, and more expensive than those used in first-line regimens. • HIV drug resistance studies are designed to determine which HIV mutations are selected by antiretroviral drugs and, in turn, how these mutations affect antiretroviral drug susceptibility and response to future antiretroviral treatment regimens. • Such studies collectively form a vital knowledge base essential for monitoring global HIV drug resistance trends, interpreting HIV genotypic tests, and updating HIV treatment guidelines. • Although HIV drug resistance data are collected in many studies, such data are often not publicly shared, prompting the need to recommend best practices to encourage and standardize HIV drug resistance data sharing. • In contrast to other viruses, sharing HIV sequences from phylogenetic studies of transmission dynamics requires additional precautions as HIV transmission is criminalized in many countries and regions. • Our recommendations are designed to ensure that the data that contribute to HIV drug resistance knowledge will be available without undue hardship to those publishing HIV drug resistance studies and without risk to people living with HIV. |
Pathogenic Leptospira are widespread in the urban wildlife of southern California
Helman SK , Tokuyama AFN , Mummah RO , Stone NE , Gamble MW , Snedden CE , Borremans B , Gomez ACR , Cox C , Nussbaum J , Tweedt I , Haake DA , Galloway RL , Monzón J , Riley SPD , Sikich JA , Brown J , Friscia A , Sahl JW , Wagner DM , Lynch JW , Prager KC , Lloyd-Smith JO . Sci Rep 2023 13 (1) 14368 ![]() Leptospirosis, the most widespread zoonotic disease in the world, is broadly understudied in multi-host wildlife systems. Knowledge gaps regarding Leptospira circulation in wildlife, particularly in densely populated areas, contribute to frequent misdiagnoses in humans and domestic animals. We assessed Leptospira prevalence levels and risk factors in five target wildlife species across the greater Los Angeles region: striped skunks (Mephitis mephitis), raccoons (Procyon lotor), coyotes (Canis latrans), Virginia opossums (Didelphis virginiana), and fox squirrels (Sciurus niger). We sampled more than 960 individual animals, including over 700 from target species in the greater Los Angeles region, and an additional 266 sampled opportunistically from other California regions and species. In the five target species seroprevalences ranged from 5 to 60%, and infection prevalences ranged from 0.8 to 15.2% in all except fox squirrels (0%). Leptospira phylogenomics and patterns of serologic reactivity suggest that mainland terrestrial wildlife, particularly mesocarnivores, could be the source of repeated observed introductions of Leptospira into local marine and island ecosystems. Overall, we found evidence of widespread Leptospira exposure in wildlife across Los Angeles and surrounding regions. This indicates exposure risk for humans and domestic animals and highlights that this pathogen can circulate endemically in many wildlife species even in densely populated urban areas. |
Inferring time of infection from field data using dynamic models of antibody decay
Borremans B , Mummah RO , Guglielmino AH , Galloway RL , Hens N , Prager KC , Lloyd-Smith JO . Methods Ecol Evol 2023 ![]() Studies of infectious disease ecology would benefit greatly from knowing when individuals were infected, but estimating this time of infection can be challenging, especially in wildlife. Time of infection can be estimated from various types of data, with antibody-level data being one of the most promising sources of information. The use of antibody levels to back-calculate infection time requires the development of a host-pathogen system-specific model of antibody dynamics, and a leading challenge in such quantitative serology approaches is how to model antibody dynamics in the absence of experimental infection data. We present a way to model antibody dynamics in a Bayesian framework that facilitates the incorporation of all available information about potential infection times and apply the model to estimate infection times of Channel Island foxes infected with Leptospira interrogans. Using simulated data, we show that the approach works well across a broad range of parameter settings and can lead to major improvements in infection time estimates that depend on system characteristics such as antibody decay rate and variation in peak antibody levels after exposure. When applied to field data we saw reductions up to 83% in the window of possible infection times. The method substantially simplifies the challenge of modelling antibody dynamics in the absence of individuals with known infection times, opens up new opportunities in wildlife disease ecology and can even be applied to cross-sectional data once the model is trained. © 2023 The Authors. Methods in Ecology and Evolution published by John Wiley & Sons Ltd on behalf of British Ecological Society. |
Transmission of yellow fever vaccine virus through blood transfusion and organ transplantation in the USA in 2021: Report of an investigation
Gould CV , Free RJ , Bhatnagar J , Soto RA , Royer TL , Maley WR , Moss S , Berk MA , Craig-Shapiro R , Kodiyanplakkal RPL , Westblade LF , Muthukumar T , Puius YA , Raina A , Hadi A , Gyure KA , Trief D , Pereira M , Kuehnert MJ , Ballen V , Kessler DA , Dailey K , Omura C , Doan T , Miller S , Wilson MR , Lehman JA , Ritter JM , Lee E , Silva-Flannery L , Reagan-Steiner S , Velez JO , Laven JJ , Fitzpatrick KA , Panella A , Davis EH , Hughes HR , Brault AC , St George K , Dean AB , Ackelsberg J , Basavaraju SV , Chiu CY , Staples JE . Lancet Microbe 2023 4 (9) e711-e721 ![]() ![]() BACKGROUND: In 2021, four patients who had received solid organ transplants in the USA developed encephalitis beginning 2-6 weeks after transplantation from a common organ donor. We describe an investigation into the cause of encephalitis in these patients. METHODS: From Nov 7, 2021, to Feb 24, 2022, we conducted a public health investigation involving 15 agencies and medical centres in the USA. We tested various specimens (blood, cerebrospinal fluid, intraocular fluid, serum, and tissues) from the organ donor and recipients by serology, RT-PCR, immunohistochemistry, metagenomic next-generation sequencing, and host gene expression, and conducted a traceback of blood transfusions received by the organ donor. FINDINGS: We identified one read from yellow fever virus in cerebrospinal fluid from the recipient of a kidney using metagenomic next-generation sequencing. Recent infection with yellow fever virus was confirmed in all four organ recipients by identification of yellow fever virus RNA consistent with the 17D vaccine strain in brain tissue from one recipient and seroconversion after transplantation in three recipients. Two patients recovered and two patients had no neurological recovery and died. 3 days before organ procurement, the organ donor received a blood transfusion from a donor who had received a yellow fever vaccine 6 days before blood donation. INTERPRETATION: This investigation substantiates the use of metagenomic next-generation sequencing for the broad-based detection of rare or unexpected pathogens. Health-care workers providing vaccinations should inform patients of the need to defer blood donation for at least 2 weeks after receiving a yellow fever vaccine. Despite mitigation strategies and safety interventions, a low risk of transfusion-transmitted infections remains. FUNDING: US Centers for Disease Control and Prevention (CDC), the Biomedical Advanced Research and Development Authority, and the CDC Epidemiology and Laboratory Capacity Cooperative Agreement for Infectious Diseases. |
Stable Flow-induced Expression of KLK10 Inhibits Endothelial Inflammation and Atherosclerosis (preprint)
Williams D , Mahmoud M , Liu R , Andueza A , Kumar S , Kang DW , Zhang J , Tamargo I , Villa-Roel N , Baek KI , Lee H , An Y , Zhang L , Tate EW , Bagchi P , Pohl J , Mosnier LO , Diamandis EP , Mihara K , Hollenberg MD , Dai Z , Jo H . bioRxiv 2021 2021.08.10.455857 Introduction Atherosclerosis preferentially occurs in arterial regions exposed to disturbed blood flow (d-flow), while regions exposed to stable flow (s-flow) are protected. The proatherogenic and atheroprotective effects of d-flow and s-flow are mediated in part by the global changes in endothelial cell gene expression, which regulates endothelial dysfunction, inflammation, and atherosclerosis. Previously, we identified Kallikrein-Related Peptidase 10 (KLK10, a secreted serine protease) as a flow-sensitive gene in arterial endothelial cells, but its role in endothelial biology and atherosclerosis was unknown.Methods and Results Here, we show that KLK10 is upregulated under s-flow conditions and downregulated under d-flow conditions using in vivo mouse models and in vitro studies with cultured endothelial cells (ECs). Single-cell RNA sequencing (scRNAseq) and scATAC sequencing (scATACseq) study using the partial carotid ligation mouse model showed flow-regulated KLK10 expression at the epigenomic and transcription levels. Functionally, KLK10 protected against d-flow-induced inflammation and permeability dysfunction in human artery ECs (HAECs). Further, treatment of mice in vivo with rKLK10 decreased arterial endothelial inflammation in d-flow regions. Additionally, rKLK10 injection or ultrasound-mediated transfection of KLK10-expressing plasmids inhibited atherosclerosis in ApoE-/- mice. Studies using pharmacological inhibitors and siRNAs revealed that the anti-inflammatory effects of KLK10 were mediated by a Protease Activated Receptors (PAR1/2)-dependent manner. However, unexpectedly, KLK10 did not cleave the PARs. Through a proteomics study, we identified HTRA1 (High-temperature requirement A serine peptidase 1), which bound and cleaved KLK10. Further, siRNA knockdown of HTRA1 prevented KLK10’s anti-inflammatory and barrier protective function in HAECs, suggesting that HTRA1 regulates KLK10 function. Moreover, KLK10 expression was significantly reduced in human coronary arteries with advanced atherosclerotic plaques compared to those with less severe plaques.Conclusion KLK10 is a flow-sensitive endothelial protein and, in collaboration with HTRA1, serves as an anti-inflammatory, barrier-protective, and anti-atherogenic factor.Competing Interest StatementThe authors have declared no competing interest. |
Mitigating outbreaks in congregate settings by decreasing the size of the susceptible population (preprint)
Blumberg S , Lu P , Hoover CM , Lloyd-Smith JO , Kwan AT , Sears D , Bertozzi SM , Worden L . medRxiv 2021 While many transmission models have been developed for community spread of respiratory pathogens, less attention has been given to modeling the interdependence of disease introduction and spread seen in congregate settings, such as prisons or nursing homes. As demonstrated by the explosive outbreaks of COVID-19 seen in congregate settings, the need for effective outbreak prevention and mitigation strategies for these settings is critical. Here we consider how interventions that decrease the size of the susceptible populations, such as vaccination or depopulation, impact the expected number of infections due to outbreaks. Introduction of disease into the resident population from the community is modeled as a branching process, while spread between residents is modeled via a compartmental model. Control is modeled as a proportional decrease in both the number of susceptible residents and the reproduction number. We find that vaccination or depopulation can have a greater than linear effect on anticipated infections. For example, assuming a reproduction number of 3.0 for density-dependent COVID-19 transmission, we find that reducing the size of the susceptible population by 20% reduced overall disease burden by 47%. We highlight the California state prison system as an example for how these findings provide a quantitative framework for implementing infection control in congregate settings. Additional applications of our modeling framework include optimizing the distribution of residents into independent residential units, and comparison of preemptive versus reactive vaccination strategies. |
Mapping the Host-Pathogen Space to Link Longitudinal and Cross-sectional Biomarker Data: Leptospira Infection in California Sea Lions (Zalophus californianus) as a Case Study (preprint)
Prager KC , Buhnerkempe MG , Greig DJ , Orr AJ , Jensen ED , Gomez F , Galloway RL , Wu Q , Gulland FMD , Lloyd-Smith JO . bioRxiv 2019 819532 Confronted with the challenge of understanding population-level processes, disease ecologists and epidemiologists often simplify quantitative data into distinct physiological states (e.g. susceptible, exposed, infected, recovered). However, data defining these states often fall along a spectrum rather than into clear categories. Hence, the host-pathogen relationship is more accurately defined using quantitative data, often integrating multiple diagnostic measures, just as clinicians do to assess their patients. We use quantitative data on a bacterial infection (Leptospira interrogans) in California sea lions (Zalophus californianus) to improve both our individual-level and population-level understanding of this host-pathogen system. We create a “host-pathogen space” by mapping multiple biomarkers of infection (e.g. serum antibodies, pathogen DNA) and disease state (e.g. serum chemistry values) from 13 longitudinally sampled, severely ill individuals to visualize and characterize changes in these values through time. We describe a clear, unidirectional trajectory of disease and recovery within this host-pathogen space. Remarkably, this trajectory also captures the broad patterns in larger cross-sectional datasets of 1456 wild sea lions in all states of health. This mapping framework enables us to determine an individual’s location in their time-course since initial infection, and to visualize the full range of clinical states and antibody responses induced by pathogen exposure, including severe acute disease, chronic subclinical infection, and recovery. We identify predictive relationships between biomarkers and outcomes such as survival and pathogen shedding, and in certain cases we can impute values for missing data, thus increasing the size of the useable dataset. Mapping the host-pathogen space and using quantitative biomarker data provides more nuanced approaches for understanding and modeling disease dynamics in a system, yielding benefits for the clinician who needs to triage patients and prevent transmission, and for the disease ecologist or epidemiologist wishing to develop appropriate risk management strategies and assess health impacts on a population scale.Author Summary A pathogen can cause a range of disease severity across different host individuals, and these presentations change over the time-course from infection to recovery. These facts complicate the work of epidemiologists and disease ecologists seeking to understand the factors governing disease spread, often working with cross-sectional data. Recognizing these facts also highlights the shortcomings of classical approaches to modeling infectious disease, which typically rely on discrete and well-defined disease states. Here we show that by analyzing multiple biomarkers of health and infection simultaneously, treating these values as quantitative rather than binary indicators, and including a modest amount of longitudinal sampling of hosts, we can create a map of the host-pathogen interaction that shows the full spectrum of disease presentations and opens doors for new insights and predictions. By accounting for individual variation and capturing changes through time since infection, this mapping framework enables more robust interpretation of cross-sectional data; e.g., to detect predictive relationships between biomarkers and key outcomes such as survival, or to assess whether observed disease is associated with the pathogen of interest. This approach can help epidemiologists, ecologists and clinicians to better study and manage the many infectious diseases that exhibit complex relationships with their hosts. |
Pathogenic Leptospira are widespread in the urban wildlife of southern California (preprint)
Helman SK , Tokuyama AFN , Mummah RO , Gamble MW , Snedden CE , Borremans B , Gomez ACR , Cox C , Nussbaum J , Tweedt I , Haake DA , Galloway RL , Monzon J , Riley SPD , Sikich JA , Brown J , Friscia A , Lynch JW , Prager KC , Lloyd-Smith JO . bioRxiv 2023 15 Leptospirosis is the most widespread zoonotic disease in the world, yet it is broadly understudied in multi-host wildlife systems. Knowledge gaps regarding Leptospira circulation in wildlife, particularly in densely populated areas, contribute to frequent misdiagnoses in humans and domestic animals. We assessed Leptospira prevalence levels and risk factors in five target wildlife species across the greater Los Angeles region: striped skunks (Mephitis mephitis), Northern raccoons (Procyon lotor), coyotes (Canis latrans), Virginia opossums (Didelphis virginiana), and fox squirrels (Sciurus niger). We sampled more than 960 individual animals, including over 700 from target species in the greater Los Angeles region, and an additional 260 sampled opportunistically from other regions and species. In the five target species, seroprevalences ranged from 5-60% and active infection prevalences ranged from 0.8-15.2% in all except fox squirrels (0%). Patterns of serologic reactivity suggest that mainland terrestrial wildlife, particularly mesocarnivores, could be the source of repeated observed introductions of Leptospira into local marine and island ecosystems. Overall, we found evidence of widespread Leptospira exposure in wildlife across Los Angeles and surrounding regions. This indicates exposure risk for humans and domestic animals and highlights that this pathogen can circulate endemically in many wildlife species even in densely populated urban areas. Copyright The copyright holder for this preprint is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. All rights reserved. No reuse allowed without permission. |
Presence of Symptoms 6 Weeks After COVID-19 Among Vaccinated and Unvaccinated U.S. Healthcare Personnel (preprint)
Mohr NM , Plumb ID , Harland KK , Pilishvili T , Fleming-Dutra KE , Krishnadasan A , Hoth KF , Saydah SH , Mankoff Z , Haran JP , Leon ES , Talan DA , Smithline HA , Hou PC , Lee LC , Lim SC , Moran GJ , Steele MT , Beiser DG , Faine B , Nandi U , Schrading WA , Chinnock B , Chipman A , Fuentes M , LoVecchio F , Clinansmith B , Landers S , Horcher A , Wallace K , Uribe L , Pathmarajah K , Poronsky KE , Hashimoto DM , Bahamon M , Romain MSt , Kean E , Krebs E , Stubbs A , Roy S , Volturo G , Higgins A , Galbraith J , Crosby JC , Mulrow M , Gonzalez E , Gierke R , Farrar JL , Xing W , Chung Y , Yousaf A , Okaro JO , Briggs-Hagen M , Abedi GR , Nyanseor S , Watts CK . medRxiv 2022 25 Importance: Although COVID-19 vaccines protect against infection and severe disease, the role of vaccination in preventing prolonged symptoms in those with subsequent infection is unclear. Objective(s): To determine differences in symptoms stratified by prior vaccination reported by healthcare personnel (HCP) 6 weeks after onset of COVID-19, and whether there were differences in timing of return to work. Design(s): Nested cohort study within a multicenter vaccine effectiveness study. HCP with COVID-19 between December 2020 and August 2021 were followed up 6 weeks after illness onset. Setting(s): Health systems in 12 U.S. states. Participant(s): HCP participating in a vaccine effectiveness study were eligible for inclusion if they had confirmed COVID-19 with either verified mRNA vaccination (symptom onset =14 days after two doses) or no prior COVID-19 vaccination. Among 681 eligible participants, 419 (61%) completed a follow-up survey approximately 6 weeks after illness onset. Exposures: Two doses of a COVID-19 mRNA vaccine compared with no COVID-19 vaccine. Main Outcomes and Measures: Presence of symptoms 6 weeks after onset of COVID-19 illness and days to return to work after COVID-19 illness. Result(s): Among 419 HCP with confirmed COVID-19, 298 (71%) reported one or more COVID-like symptoms 6 weeks after illness onset, with a lower prevalence among vaccinated participants (60.6%) compared with unvaccinated participants (60.6% vs. 79.1%; aRR 0.70, 95% CI 0.58-0.84). Vaccinated HCP returned to work a median 2.0 days (95% CI 1.0-3.0) sooner than unvaccinated HCP (aHR 1.37; 95% CI, 1.04-1.79). Conclusion(s): A history of two doses of COVID-19 mRNA vaccine among HCP with COVID-19 illness was associated with decreased risk of COVID-like symptoms at 6 weeks and earlier to return to work. Vaccination is associated with improved recovery from COVID-19, in addition to preventing symptomatic infection. Copyright The copyright holder for this preprint is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. All rights reserved. No reuse allowed without permission. |
Inferring time of infection from field data using dynamic models of antibody decay (preprint)
Borremans B , Mummah RO , Guglielmino AH , Galloway RL , Hens N , Prager KC , Lloyd-Smith JO . bioRxiv 2022 07 ![]() Studies of infectious disease ecology often rely heavily on knowing when individuals were infected, but estimating this time of infection can be challenging, especially in wildlife. Time of infection can be estimated from various types of data, with antibody level data being one of the most promising sources of information. The use of antibody levels to back-calculate infection time requires the development of a host-pathogen system-specific model of antibody dynamics, and a leading challenge in such quantitative serology approaches is how to model antibody dynamics in the absence of experimental infection data. Here, we present a way to do this in a Bayesian framework that facilitates the incorporation of all available information about potential infection times. We apply the model to estimate infection times of Channel Island foxes infected with Leptospira interrogans, leading to reductions of 51-92% in the window of possible infection times. Using simulated data, we show that the approach works well across a broad range of parameter settings and can lead to major improvements of infection time estimates that depend on system characteristics such as antibody decay rate and variation in peak antibody levels after exposure. The method substantially simplifies the challenge of modeling antibody dynamics in the absence of individuals with known infection times, opens up new opportunities in wildlife disease ecology, and can even be applied to cross-sectional data once the model is trained. Copyright The copyright holder for this preprint is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under a CC-BY-NC-ND 4.0 International license. |
Respiratory syncytial virus (RSV) disease and prevention products: Knowledge, attitudes, and preferences of Kenyan healthcare workers in two counties in 2021
Nyawanda BO , Opere VA , Nyiro JU , Vodicka E , Fleming JA , Baral R , Khan S , Pecenka C , Ayugi JO , Atito R , Ougo J , Bigogo G , Emukule GO , Otieno NA , Munywoki PK . Vaccines (Basel) 2023 11 (6) Respiratory syncytial virus (RSV) is a major cause of lower respiratory tract infection (LRTI) among infants under 6 months of age. Yet, in Kenya, little is known about healthcare workers' (HCWs) knowledge, attitudes, and perceptions around RSV disease and the prevention products under development. Between September and October 2021, we conducted a mixed methods cross-sectional survey to assess HCWs' knowledge, attitudes, and perceptions of RSV disease and RSV vaccinations in two counties. We enrolled HCWs delivering services directly at maternal and child health (MCH) departments in selected health facilities (frontline HCWs) and health management officers (HMOs). Of the 106 respondents, 94 (88.7%) were frontline HCWs, while 12 were HMOs. Two of the HMOs were members of the Kenya National Immunization Technical Advisory Group (KENITAG). Of the 104 non-KENITAG HCWs, only 41 (39.4%) had heard about RSV disease, and 38/41 (92.7%) felt that pregnant women should be vaccinated against RSV. Most participants would recommend a single-dose vaccine schedule (n = 62, 58.5%) for maximal adherence and compliance (n = 38/62, 61.3%), single dose/device vaccines (n = 50/86, 58.1%) to prevent wastage and contamination, and maternal vaccination through antenatal care clinics (n = 53, 50%). We found the need for increased knowledge about RSV disease and prevention among Kenyan HCWs. |
Aerosol and surface stability of HCoV-19 (SARS-CoV-2) compared to SARS-CoV-1.
van Doremalen N , Bushmaker T , Morris DH , Holbrook MG , Gamble A , Williamson BN , Tamin A , Harcourt JL , Thornburg NJ , Gerber SI , Lloyd-Smith JO , de Wit E , Munster VJ . medRxiv 2020 ![]() A novel human coronavirus, now named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, referred to as HCoV-19 here) that emerged in Wuhan, China in late 2019 is now causing a pandemic1. Here, we analyze the aerosol and surface stability of HCoV-19 and compare it with SARS-CoV-1, the most closely related human coronavirus.2 We evaluated the stability of HCoV-19 and SARS-CoV-1 in aerosols and on different surfaces and estimated their decay rates using a Bayesian regression model (see Supplementary Appendix). All experimental measurements are reported as mean across 3 replicates. |
Development of air purifier operation guidelines using grey box models for the concentrations of particulate matter in elementary school classrooms
Park S , Song D , Jo YM , Park JH , Lee TJ , Koo J . Aerosol Sci Tech 2023 57 (5) 467-485 Considering the hazardous effects of particulate matter (PM) exposure on students and teachers and the high PM concentration issue in South Korea, air purifiers have recently been installed in most classrooms to improve air quality. However, some on-site challenges, such as operational costs and noise, have been issues with the continuous operation of air purifiers. Therefore, a guideline is needed to dynamically predict the indoor PM concentration based on the changes in outdoor PM concentration and activate the air purifiers only when necessary. This study develops a grey-box model that uses measured data and physical differential equations to perform the given objective and verifies its accuracy using ASTM D5157. Modeling and analysis results have obtained information that can form the basis for developing guidelines to address PM issues in schools: The air purifier should be operated during periods where the predicted values exceed the limit in closed windows and the air purifier is not operating. It was also confirmed that the need for the operation of the air purifier varies between schools and classrooms under the same outdoor PM concentration. Indoor PM concentration increased significantly after students' simultaneous mass movement, necessitating air purifiers' operation before and after the events. The pre-filter of the heater also aided in the removal of coarse PM. Additionally, the limitations and future development directions of the model were discussed. |
Ideational factors and their association with insecticide treated net use in Magoe District, Mozambique
Yukich JO , Hutchinson P , Candrinho B , Butts J , Murimirgua F , Eisele TP , Zulliger R . Malar J 2022 21 (1) 387 BACKGROUND: Insecticide treated bed nets (ITN) are considered a core malaria vector control tool by the WHO and are the main contributor to the large decline in malaria burden in sub-Saharan Africa over the past 20 years, but they are less effective if they are not broadly and regularly used. ITN use may depend on factors including temperature, relative humidity, mosquito density, seasonality, as well as ideational or psychosocial factors including perceptions of nets and perceptions of net use behaviours. METHODS: A cross-sectional household survey was conducted as part of a planned randomized controlled trial in Magoe District, Mozambique. Interviewers captured data on general malaria and ITN perceptions including ideational factors related to perceived ITN response efficacy, self-efficacy to use an ITN, and community norms around ITN using a standardized questionnaire. Only households with sufficient ITNs present for all children to sleep under (at least one ITN for every two children under the age of five years) were eligible for inclusion in the study. Additional questions were added about seasonality and frequency of ITN use. RESULTS: One-thousand six hundred sixteen mother-child dyads were interviewed. Responses indicated gaps in use of existing nets and net use was largely independent of ideational factors related to ITNs. Self-reported ITN use varied little by season nor meaningfully when different methods were used to solicit responses on net use behaviour. Mothers' perceived response efficacy of ITNS was negatively associated with net use (high perceived response efficacy reduced the log-odds of net use by 0.27 (95% CI - 0.04 to - 0.51), implying that stronger beliefs in the effectiveness of ITNs might result in reduced net use among their children. CONCLUSIONS: In this context, ITN use among children was not clearly related to mothers' ideational factors measured in the study. Scales used in solicitation of ideation around ITN use and beliefs need careful design and testing across a broader range of populations in order to identify ideational factors related to ITN use among those with access. |
Uptake and effect of universal test-and-treat on twelve months retention and initial virologic suppression in routine HIV program in Kenya
Kimanga DO , Oramisi VA , Hassan AS , Mugambi MK , Miruka FO , Muthoka KJ , Odhiambo JO , Yegon PK , Omoro GO , Mbaire C , Masamaro KM , Njogo SM , Barker JL , Ngugi CN . PLoS One 2022 17 (11) e0277675 Early combination antiretroviral therapy (cART), as recommended in WHO's universal test-and-treat (UTT) policy, is associated with improved linkage to care, retention, and virologic suppression in controlled studies. We aimed to describe UTT uptake and effect on twelve-month non-retention and initial virologic non-suppression (VnS) among HIV infected adults starting cART in routine HIV program in Kenya. Individual-level HIV service delivery data from 38 health facilities, each representing 38 of the 47 counties in Kenya were analysed. Adults (>15 years) initiating cART between the second-half of 2015 (2015HY2) and the first-half of 2018 (2018HY1) were followed up for twelve months. UTT was defined based on time from an HIV diagnosis to cART initiation and was categorized as same-day, 1-14 days, 15-90 days, and 91+ days. Non-retention was defined as individuals lost-to-follow-up or reported dead by the end of the follow up period. Initial VnS was defined based on the first available viral load test with >400 copies/ml. Hierarchical mixed-effects survival and generalised linear regression models were used to assess the effect of UTT on non-retention and VnS, respectively. Of 8592 individuals analysed, majority (n = 5864 [68.2%]) were female. Same-day HIV diagnosis and cART initiation increased from 15.3% (2015HY2) to 52.2% (2018HY1). The overall non-retention rate was 2.8 (95% CI: 2.6-2.9) per 100 person-months. When compared to individuals initiated cART 91+ days after a HIV diagnosis, those initiated cART on the same day of a HIV diagnosis had the highest rate of non-retention (same-day vs. 91+ days; aHR, 1.7 [95% CI: 1.5-2.0], p<0.001). Of those included in the analysis, 5986 (69.6%) had a first viral load test done at a median of 6.3 (IQR, 5.6-7.6) months after cART initiation. Of these, 835 (13.9%) had VnS. There was no association between UTT and VnS (same-day vs. 91+ days; aRR, 1.0 [95% CI: 0.9-1.2], p = 0.664). Our findings demonstrate substantial uptake of the UTT policy but poor twelve-month retention and lack of an association with initial VnS from routine HIV settings in Kenya. These findings warrant consideration for multi-pronged program interventions alongside UTT policy for maximum intended benefits in Kenya. |
Genetic and phenotypic stability of poliovirus shed from infants who received novel type 2 or Sabin type 2 oral poliovirus vaccines in Panama: an analysis of two clinical trials.
Wahid R , Mercer LD , De Leon T , DeAntonio R , Sáez-Llorens X , Macadam A , Chumakov K , Strating J , Koel B , Konopka-Anstadt JL , Oberste MS , Burns CC , Andino R , Tritama E , Bandyopadhyay AS , Aguirre G , Rüttimann R , Gast C , Konz JO . Lancet Microbe 2022 3 (12) e912-e921 ![]() ![]() BACKGROUND: Sabin strains used in oral poliovirus vaccines (OPV) can revert to virulence and, in rare instances, cause disease or generate vaccine-derived strains leading to outbreaks in areas of low immunisation coverage. A novel OPV2 (nOPV2) was designed to stabilise the viral genome against reversion and reduce recombination events that might lead to virulent strains. In this study, we evaluated the genetic and phenotypic stability of shed poliovirus following administration of one dose of monovalent OPV2 (mOPV2) or nOPV2 to infants aged 18-22 weeks. METHODS: In two similarly designed clinical trials (NCT02521974 and NCT03554798) conducted in Panama, infants aged 18-22-weeks, after immunisation with three doses of bivalent OPV (types 1 and 3) and one dose of inactivated poliovirus vaccine, were administered one or two doses of mOPV2 or nOPV2. In this analysis of two clinical trials, faecally shed polioviruses following one dose of mOPV2 or nOPV2 were isolated from stools meeting predetermined criteria related to sample timing and viral presence and quantity and assessed for nucleotide polymorphisms using next-generation sequencing. A transgenic mouse neurovirulence test was adapted to assess the effect of the possible phenotypic reversion of shed mOPV2 and nOPV2 with a logistic regression model. FINDINGS: Of the 91 eligible samples, 86 were able to be sequenced, with 72 evaluated in the transgenic mouse assay. Sabin-2 poliovirus reverts rapidly at nucleotide 481, the primary attenuation site in domain V of the 5' untranslated region of the genome. There was no evidence of neurovirulence-increasing polymorphisms in domain V of shed nOPV2. Reversion of shed Sabin-2 virus corresponded with unadjusted paralysis rates of 47·6% at the 4 log(10) 50% cell culture infectious dose (CCID(50)) and 76·7% at the 5 log(10) CCID(50) inoculum levels, with rates of 2·8% for 4 log(10) CCID(50) and 11·8% for 5 log(10) CCID(50) observed for shed nOPV2 samples. The estimated adjusted odds ratio at 4·5 log(10) of 0·007 (95% CI 0·002-0·023; p<0·0001) indicates significantly reduced odds of mouse paralysis from virus obtained from nOPV2 recipients compared with mOPV2 recipients. INTERPRETATION: The data indicate increased genetic stability of domain V of nOPV2 relative to mOPV2, with significantly lower neurovirulence of shed nOPV2 virus compared with shed mOPV2. While this vaccine is currently being deployed under an emergency use listing, the data on the genetic stability of nOPV2 will support further regulatory and policy decision-making regarding use of nOPV2 in outbreak responses. FUNDING: Bill & Melinda Gates Foundation. |
Severe arboviral neuroinvasive disease in patients on rituximab therapy: A review
Kapadia RK , Staples JE , Gill CM , Fischer M , Khan E , Laven JJ , Panella A , Velez JO , Hughes HR , Brault A , Pastula DM , Gould CV . Clin Infect Dis 2022 76 (6) 1142-1148 With increasing use of rituximab and other B-cell depleting monoclonal antibodies for multiple indications, infectious complications are being recognized. We summarize clinical findings of patients on rituximab with arboviral diseases identified through literature review or consultation with the Centers for Disease Control and Prevention. We identified 21 patients on recent rituximab therapy who were diagnosed with an arboviral disease caused by West Nile, tick-borne encephalitis, eastern equine encephalitis, Cache Valley, Jamestown Canyon, and Powassan viruses. All reported patients had neuroinvasive disease. The diagnosis of arboviral infection required molecular testing in 20 (95%) patients. Median illness duration was 36 days (range, 12 days-1 year) and 15/19 (79%) patients died from their illness. Patients on rituximab with arboviral disease can have a severe or prolonged course with an absence of serologic response. Patients should be counseled about mosquito and tick bite prevention when receiving rituximab and other B-cell depleting therapies. |
Laboratory evaluation of RealStar Yellow Fever Virus RT-PCR kit 1.0 for potential use in the global yellow fever laboratory network
Basile AJ , Niedrig M , Lambert AJ , Meurant R , Brault AC , Domingo C , Goodman CH , Johnson BW , Mossel EC , Mulders MN , Velez JO , Hughes HR . PLoS Negl Trop Dis 2022 16 (9) e0010770 BACKGROUND: Early detection of human yellow fever (YF) infection in YF-endemic regions is critical to timely outbreak mitigation. African National Laboratories chiefly rely on serological assays that require confirmation at Regional Reference Laboratories, thus delaying results, which themselves are not always definitive often due to antibody cross-reactivity. A positive molecular test result is confirmatory for YF; therefore, a standardized YF molecular assay would facilitate immediate confirmation at National Laboratories. The WHO-coordinated global Eliminate Yellow Fever Epidemics Laboratory Technical Working Group sought to independently evaluate the quality and performance of commercial YF molecular assays relevant to use in countries with endemic YF, in the absence of stringent premarket assessments. This report details a limited laboratory WHO-coordinated evaluation of the altona Diagnostics RealStar Yellow Fever Virus RT-PCR kit 1.0. METHODOLOGY AND PRINCIPAL FINDINGS: Specific objectives were to assess the assay's ability to detect YF virus strains in human serum from YF-endemic regions, determine the potential for interference and cross-reactions, verify the performance claims as stated by the manufacturer, and assess usability. RNA extracted from normal human serum spiked with YF virus showed the assay to be precise with minimal lot-to-lot variation. The 95% limit of detection calculated was approximately 1,245 RNA copies/ml [95% confidence interval 497 to 1,640 copies/ml]. Positive results were obtained with spatially and temporally diverse YF strains. The assay was specific for YF virus, was not subject to endogenous or exogenous interferents, and was clinically sensitive and specific. A review of operational characteristics revealed that a positivity cutoff was not defined in the instructions for use, but otherwise the assay was user-friendly. CONCLUSIONS AND SIGNIFICANCE: The RealStar Yellow Fever Virus RT-PCR kit 1.0 has performance characteristics consistent with the manufacturer's claims and is suitable for use in YF-endemic regions. Its use is expected to decrease YF outbreak detection times and be instrumental in saving lives. |
Colorado tick fever virus in the far west: Forgotten, but not gone
Padgett KA , Kjemtrup A , Novak M , Velez JO , Panella N . Vector Borne Zoonotic Dis 2022 22 (8) 443-448 In the past few decades, reported human cases of Colorado tick fever in the western United States have decreased dramatically. The goal of this study was to conduct surveillance for Colorado tick fever virus (CTFV) in Dermacentor ticks in recreational sites in Colorado, Wyoming, and California to determine whether the virus is still present in Dermacentor ticks from these states. Surveillance focused on regions where surveys had been conducted in the 1950s, 1960s, and 1970s. Adult Rocky Mountain wood ticks (Dermacentor andersoni), Pacific Coast ticks (Dermacentor occidentalis), and winter ticks (Dermacentor albipictus) were tested by PCR. A subset of PCR-positive D. andersoni ticks (n=7) were cultured in Vero cells. CTFV-positive Rocky Mountain wood ticks were found in all states: Colorado (58% prevalence), Wyoming (21%), and California (4%). Although no winter ticks tested positive, Pacific Coast ticks tested positive in one county (Siskiyou County, 15% prevalence) and were positive only in a location that also maintained Rocky Mountain wood ticks and golden mantled ground squirrels, a known CTFV host. In summary, CTFV is prevalent in D. andersoni and D. occidentalis in regions where they are sympatric in California and in D. andersoni in Colorado and Wyoming. Although the number of human CTFV cases has declined dramatically, this decrease in reported disease does not appear to be due to the disappearance or even the decline in prevalence of this virus in ticks in historically endemic regions of the country. |
Transfusion-Transmitted Cache Valley Virus Infection in a Kidney Transplant Recipient with Meningoencephalitis.
Al-Heeti O , Wu EL , Ison MG , Saluja RK , Ramsey G , Matkovic E , Ha K , Hall S , Banach B , Wilson MR , Miller S , Chiu CY , McCabe M , Bari C , Zimler RA , Babiker H , Freeman D , Popovitch J , Annambhotla P , Lehman JA , Fitzpatrick K , Velez JO , Davis EH , Hughes HR , Panella A , Brault A , Erin Staples J , Gould CV , Tanna S . Clin Infect Dis 2022 76 (3) e1320-e1327 ![]() ![]() BACKGROUND: Cache Valley virus (CVV) is a mosquito-borne virus that is a rare cause of disease in humans. In the Fall of 2020, a patient developed encephalitis six weeks following kidney transplantation and receipt of multiple blood transfusions. METHODS: After ruling out more common etiologies, metagenomic next-generation sequencing (mNGS) of cerebrospinal fluid (CSF) was performed. We reviewed the medical histories of the index kidney recipient, organ donor, and recipients of other organs from the same donor and conducted a blood traceback investigation to evaluate blood transfusion as a possible source of infection in the kidney recipient. We tested patient specimens by reverse transcription-polymerase chain reaction (RT-PCR), plaque reduction neutralization test (PRNT), cell culture, and whole genome sequencing. RESULTS: CVV was detected in CSF from the index patient by mNGS, and this result was confirmed by RT-PCR, viral culture, and additional whole genome sequencing. The organ donor and other organ recipients had no evidence of infection with CVV by molecular or serologic testing. Neutralizing antibodies against CVV were detected in serum from a donor of red blood cells received by the index patient immediately prior to transplant. CVV neutralizing antibodies were also detected in serum from a patient who received the co-component plasma from the same blood donation. CONCLUSION: Our investigation demonstrates probable CVV transmission through blood transfusion. Clinicians should consider arboviral infections in unexplained meningoencephalitis after blood transfusion or organ transplantation. The use of mNGS testing might facilitate detection of rare, unexpected infections, particularly in immunocompromised patients. |
Modeling scenarios for mitigating outbreaks in congregate settings.
Blumberg S , Lu P , Kwan AT , Hoover CM , Lloyd-Smith JO , Sears D , Bertozzi SM , Worden L . PLoS Comput Biol 2022 18 (7) e1010308 The explosive outbreaks of COVID-19 seen in congregate settings such as prisons and nursing homes, has highlighted a critical need for effective outbreak prevention and mitigation strategies for these settings. Here we consider how different types of control interventions impact the expected number of symptomatic infections due to outbreaks. Introduction of disease into the resident population from the community is modeled as a stochastic point process coupled to a branching process, while spread between residents is modeled via a deterministic compartmental model that accounts for depletion of susceptible individuals. Control is modeled as a proportional decrease in the number of susceptible residents, the reproduction number, and/or the proportion of symptomatic infections. This permits a range of assumptions about the density dependence of transmission and modes of protection by vaccination, depopulation and other types of control. We find that vaccination or depopulation can have a greater than linear effect on the expected number of cases. For example, assuming a reproduction number of 3.0 with density-dependent transmission, we find that preemptively reducing the size of the susceptible population by 20% reduced overall disease burden by 47%. In some circumstances, it may be possible to reduce the risk and burden of disease outbreaks by optimizing the way a group of residents are apportioned into distinct residential units. The optimal apportionment may be different depending on whether the goal is to reduce the probability of an outbreak occurring, or the expected number of cases from outbreak dynamics. In other circumstances there may be an opportunity to implement reactive disease control measures in which the number of susceptible individuals is rapidly reduced once an outbreak has been detected to occur. Reactive control is most effective when the reproduction number is not too high, and there is minimal delay in implementing control. We highlight the California state prison system as an example for how these findings provide a quantitative framework for understanding disease transmission in congregate settings. Our approach and accompanying interactive website (https://phoebelu.shinyapps.io/DepopulationModels/) provides a quantitative framework to evaluate the potential impact of policy decisions governing infection control in outbreak settings. |
Effect of the ABCA1 agonist CS-6253 on amyloid- and lipoprotein metabolism in cynomolgus monkeys
Noveir SD , Kerman BE , Xian H , Meuret C , Smadi S , Martinez AE , Johansson J , Zetterberg H , Parks BA , Kuklenyik Z , Mack WJ , Johansson JO , Yassine HN . Alzheimers Res Ther 2022 14 (1) 87 BACKGROUND: Inducing brain ATP-binding cassette 1 (ABCA1) activity in Alzheimer's disease (AD) mouse models is associated with improvement in AD pathology. The purpose of this study was to investigate the effects of the ABCA1 agonist peptide CS-6253 on amyloid-β peptides (Aβ) and lipoproteins in plasma and cerebrospinal fluid (CSF) of cynomolgus monkeys, a species with amyloid and lipoprotein metabolism similar to humans. METHODS: CS-6253 peptide was injected intravenously into cynomolgus monkeys at various doses in three different studies. Plasma and CSF samples were collected at several time points before and after treatment. Levels of cholesterol, triglyceride (TG), lipoprotein particles, apolipoproteins, and Aβ were measured using ELISA, ion-mobility analysis, and asymmetric-flow field-flow fractionation (AF4). The relationship between the change in levels of these biomarkers was analyzed using multiple linear regression models and linear mixed-effects models. RESULTS: Following CS-6253 intravenous injection, within minutes, small plasma high-density lipoprotein (HDL) particles were increased. In two independent experiments, plasma TG, apolipoprotein E (apoE), and Aβ42/40 ratio were transiently increased following CS-6253 intravenous injection. This change was associated with a non-significant decrease in CSF Aβ42. Both plasma total cholesterol and HDL-cholesterol levels were reduced following treatment. AF4 fractionation revealed that CS-6253 treatment displaced apoE from HDL to intermediate-density- and low density-lipoprotein (IDL/LDL)-sized particles in plasma. In contrast to plasma, CS-6253 had no effect on the assessed CSF apolipoproteins or lipids. CONCLUSIONS: Treatment with the ABCA1 agonist CS-6253 appears to favor Aβ clearance from the brain. |
Evaluation of Whatman FTA cards for the preservation of yellow fever virus RNA for use in molecular diagnostics.
Davis EH , Velez JO , Russell BJ , Basile AJ , Brault AC , Hughes HR . PLoS Negl Trop Dis 2022 16 (6) e0010487 ![]() ![]() Yellow fever virus (YFV) is a flavivirus that frequently causes outbreaks of hemorrhagic fever in Africa and South America and is considered a reemerging public health threat. Accurate diagnosis of yellow fever (YF) disease is critical as one confirmed case constitutes an outbreak and may trigger a mass vaccination campaign. Highly sensitive and specific molecular diagnostics have been developed; however, these assays require maintenance of cold-chain during transport of specimens to prevent the degradation of viral RNA prior to testing. Such cold-chain requirements are difficult to meet in some regions. In this study, we investigated Whatman FTA cards as an alternative stabilization method of YFV RNA for use in molecular diagnosis. Using contrived specimens, linear regression analysis showed that RNA detection from a single 6mm FTA card punch was significantly less sensitive than traditional RNA extraction; however, pooling RNA extracted from two FTA punches significantly lowered the limit of detection to be equal to that of the traditional RNA extraction gold standard. In experiments addressing the ability of FTA card methodology to stabilize YFV RNA at variable temperature, RNA could be detected for more than two weeks following storage at 25°C. Even more promising, YFV RNA was detectable on cards held at 37°C from two days to over two weeks depending on viral input. FTA cards were also shown to stabilize YFV RNA at high humidity if cards were desiccated prior to inoculation. These results support that FTA cards could be cost effective and easy to use in molecular diagnosis of YF, preserving viral RNA to allow for positive diagnoses in situations where maintaining cold-chain is not feasible. |
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