Last data update: Dec 02, 2024. (Total: 48272 publications since 2009)
Records 1-30 (of 173 Records) |
Query Trace: Williamson D[original query] |
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Using location-based services data to map and evaluate a community design intervention to increase bicycling, Denver, Colorado
Park YS , King RJ , Pejavara A , Hathaway K , Wergin J , Townley C , Leonard S , Williamson JM , Galuska DA , Fulton JE . Prev Chronic Dis 2024 21 E80 |
Universal smoking machine adaptor for tobacco product testing
El-Hellani A , Watson CH , Huang M , Wilson CW , Fleshman CC , Petitti R , Pancake M , Bennett C , Keller-Hamilton BL , Jones J , Tran H , Bravo Cardenas R , Mays D , Ye W , Borthwick RP , Schaff J , Williamson RL , Wagener TL , Brinkman MC . Tob Control 2024 SIGNIFICANCE: Historically, tobacco product emissions testing using smoking machines has largely focused on combustible products, such as cigarettes and cigars. However, the popularity of newer products, such as electronic cigarettes (e-cigarettes), has complicated emissions testing because the products' mouth-end geometries do not readily seal with existing smoking and vaping machines. The demand for emissions data on popularly used products has led to inefficient and non-standardised solutions, such as laboratories making their geometry-specific custom adaptors and/or employing flexible tubing, for each unique mouth-end geometry tested. A user-friendly, validated, universal smoking machine adaptor (USMA) is needed for testing the variety of tobacco products reflecting consumer use, including e-cigarettes, heated tobacco products, cigarettes, plastic-tipped cigarillos and cigars. METHODS: A prototype USMA that is compatible with existing smoking/vaping machines was designed and fabricated. The quality of the seal between the USMA and different tobacco products, including e-cigarettes, cigars and cigarillos, was evaluated by examining the leak rate. RESULTS: Unlike commercial, product-specific adaptors, the USMA seals well with a wide range of tobacco product mouth-end geometries and masses. This includes e-cigarettes with non-cylindrical mouth ends and cigarillos with cuboid-like plastic tips. USMA leak rates were lower than or equivalent to commercial, product-specific adaptors. CONCLUSION: This report provides initial evidence that the USMA seals reliably with a variety of tobacco product mouth-end geometries and can be used with existing linear smoking/vaping machines to potentially improve the precision, repeatability and reproducibility of machine smoke yield data. Accurate and reproducible emissions testing is critical for regulating tobacco products. |
Benchmarking a universal smoking machine adaptor for tobacco product testing
El-Hellani A , Watson CH , Huang M , Wilson CW , Fleshman CC , Tran H , Chafin D , McGuigan M , Bravo Cardenas R , Petitti R , Pancake M , Bennett C , Mays D , Keller-Hamilton BL , Jones J , Ye W , Schaff J , Borthwick RP , Williamson RL , Wagener TL , Brinkman MC . Tob Control 2024 SIGNIFICANCE: Characterisation of tobacco product emissions is an important step in assessing their impact on public health. Accurate and repeatable emissions data require that a leak-tight seal be made between the smoking or vaping machine and the mouth-end of the tobacco product being tested. This requirement is challenging because of the variety of tobacco product mouth-end geometries being puffed on by consumers today. We developed and tested a prototype universal smoking machine adaptor (USMA) that interfaces with existing machines and reliably seals with a variety of tobacco product masses and geometries. METHODS: Emissions were machine-generated using the USMA and other available adaptors for a variety of electronic cigarettes (n=7 brands), cigars (n=4), cigarillos (n=2), a heated tobacco product, and a reference cigarette (1R6F), and mainstream total particulate matter (TPM) and nicotine were quantified. Data variability (precision, n≥10 replicates/brand) for all products and error (accuracy) from certified values (1R6F) were compared across adaptors. RESULTS: TPM and nicotine emissions generated using the USMA were accurate, precise and agreed with certified values for the 1R6F reference cigarette. Replicate data indicate that USMA repeatability across all tobacco products tested generally meets or exceeds that from the comparison adaptors and extant data. CONCLUSION: The USMA seals well with a variety of combustible tobacco products, e-cigarettes with differing geometries and plastic-tipped cigarillos. Variability for all measures was similar or smaller for the USMA compared with other adaptors. |
Notes from the field: Increases in imported malaria cases - three southern U.S. Border jurisdictions, 2023
Mitchell CL , Kennar A , Vasquez Y , Noris K , Williamson T , Mannell A , Taylor A , Ruberto I , Cullen TA , Singletary M , Shah S , Ocaranza H , Rodriguez Lainz A , Mace KE . MMWR Morb Mortal Wkly Rep 2024 73 (18) 417-419 Malaria is a severe and potentially fatal mosquitoborne disease caused by infection with Plasmodium spp. parasites. Although malaria is no longer endemic in the United States, imported infections are reported annually; the primary risk group has been U.S. residents traveling to areas where malaria is endemic (1). In 2023, sporadic locally acquired mosquito-transmitted malaria cases were reported in several U.S. states (2,3). This report describes increases in imported malaria cases in 2023 compared with 2022 in three public health jurisdictions along the U.S. southern border. |
Interaction of HLA-DRB1 * 1501 and TNF-Alpha in a Population-based Case-control Study of Multiple Sclerosis.
Williamson DM , Marrie RA , Ashley-Koch A , Satten GA . Immunol Infect Dis 2013 1 (1) 10-17 This study was conducted to determine whether single nucleotide polymorphisms (SNPs) in nine genes (human leukocyte antigen (HLA), T cell receptor beta (TCA receptor β), tumor necrosis factor α (TNF α), tumor necrosis factor β (TNF β), apolipoprotein E (APOE), interleukin 7 receptor alpha chain (IL7RA) interleukin 2 receptor alpha chain (IL2RA) myelin basic protein (MBP) and vitamin D receptor (VDR)) associated with multiple sclerosis (MS) could be replicated in a population-based sample, and to determine if these associations are modified by presence of HLA DRB1*1501. DNA was available from 722 individuals (223 with MS and 499 controls) who participated in a population-based case-control study. Cases and controls were matched on ancestry, age, gender and geographic area. HLA DRB1*1501 risk allele (T) was confirmed in this population using a genotypic test, controlling for multiple comparisons. Examining the effect of each SNP in the presence or absence of the HLA DRB1*1501 risk allele identified significant associations with TNF α -1031 (rs1799964) among those without the HLA risk allele. No additional interactions were significant in a cases-only analysis. Our results indicate that an interaction between SNPs in TNF α and HLA DRB1*1501 may influence the risk of developing MS. |
Heavy metals, organic solvents, and multiple sclerosis: An exploratory look at gene-environment interactions.
Napier MD , Poole C , Satten GA , Ashley-Koch A , Marrie RA , Williamson DM . Arch Environ Occup Health 2016 71 (1) 26-34 Exposure to heavy metals and organic solvents are potential etiologic factors for multiple sclerosis (MS), but their interaction with MS-associated genes is under-studied. The authors explored the relationship between environmental exposure to lead, mercury, and solvents and 58 single-nucleotide polymorphisms (SNPs) in MS-associated genes. Data from a population-based case-control study of 217 prevalent MS cases and 496 age-, race-, gender-, and geographically matched controls were used to fit conditional logistic regression models of the association between the chemical, gene, and MS, adjusting for education and ancestry. MS cases were more likely than controls to report lead (odds ratio [OR] = 2.03; 95% confidence interval [CI]: 1.07, 3.86) and mercury exposure (OR = 2.06; 95% CI: 1.08, 3.91). Findings of potential gene-environment interactions between SNPs in TNF-α, TNF-β, TCA-β, VDR, MBP, and APOE, and lead, mercury, or solvents should be considered cautiously due to limited sample size. |
An antibody-free evaluation of an mRNA COVID-19 vaccine
Branham PJ , Cooper HC , Williamson YM , Najjar FN , Sutton WJH , Pierce-Ruiz CL , Barr JR , Williams TL . Biologicals 2023 85 101738 This manuscript describes the use of an analytical assay that combines transfection of mammalian cells and isotope dilution mass spectrometry (IDMS) for accurate quantification of antigen expression. Expired mRNA COVID-19 vaccine material was stored at 4 °C, room temperature (∼25 °C), and 56 °C over a period of 5 weeks. The same vaccine was also exposed to 5 freeze-thaw cycles. Every week, the spike protein antigenic expression in mammalian (BHK-21) cells was evaluated. Housekeeping proteins, β-actin and GAPDH, were simultaneously quantified to account for the variation in cell counts that occurs during maintenance and growth of cell cultures. Data show that vaccine stored at elevated temperatures results in reduced spike protein expression. Also, maintaining the vaccine in ultracold conditions or exposing the vaccine to freeze-thaw cycles had less effect on the vaccine's ability to produce the antigen in mammalian cells. We describe the use of IDMS as an antibody-free means to accurately quantify expressed protein from mammalian cells transfected with mRNA vaccine. |
Systematic review and meta-analysis of seasonal malaria chemoprevention
Thwing J , Williamson J , Cavros I , Gutman JR . Am J Trop Med Hyg 2023 110 (1) 20-31 Seasonal malaria chemoprevention (SMC) for children under 5 years of age for up to four monthly cycles during malaria transmission season was recommended by the WHO in 2012 and has been implemented in 13 countries in the Sahel, reaching more than 30 million children annually. Malaria control programs implementing SMC have asked the WHO to consider expanding the age range or number of monthly cycles. We conducted a systematic review and meta-analysis of SMC among children up to 15 years of age and up to six monthly cycles. Twelve randomized studies were included, with outcomes stratified by age (< 5/≥ 5 years), by three or four versus five or six cycles, and by drug where possible. Drug regimens included sulfadoxine-pyrimethamine + amodiaquine, amodiaquine-artesunate, and sulfadoxine-pyrimethamine + artesunate. Included studies were all conducted in Sahelian countries in which high-grade resistance to sulfadoxine-pyrimethamine was rare and in zones with parasite prevalence ranging from 1% to 79%. Seasonal malaria chemoprevention resulted in substantial reductions in uncomplicated malaria incidence measured during that transmission season (rate ratio: 0.27, 95% CI: 0.25-0.29 among children < 5 years; rate ratio: 0.27, 95% CI: 0.25-0.30 among children ≥ 5 years) and in the prevalence of malaria parasitemia measured within 4-6 weeks from the final SMC cycle (risk ratio: 0.38, 95% CI: 0.34-0.43 among children < 5 years; risk ratio: 0.23, 95% CI: 0.11-0.48 among children ≥ 5 years). In high-transmission zones, SMC resulted in a moderately reduced risk of any anemia (risk ratio: 0.77, 95% CI: 0.72-0.83 among children < 5 years; risk ratio: 0.70, 95% CI: 0.52-0.95 among children ≥ 5 years [one study]). Children < 10 years of age had a moderate reduction in severe malaria (risk ratio: 0.53, 95% CI: 0.37-0.76) but no evidence of a mortality reduction. The evidence suggests that in areas in which sulfadoxine-pyrimethamine and amodiaquine remained efficacious, SMC effectively reduced malaria disease burden among children both < 5 and ≥ 5 years old and that the number of cycles should be commensurate with the length of the transmission season, up to six cycles. |
Improving health information system for malaria program management: Malaria Frontline Project lessons learned from Kano and Zamfara States, Nigeria, 2016-2019
Adewole A , Ajumobi O , Waziri N , Umar A , Bala U , Gidado S , Nguku P , Uhomoibhi P , Muhammad B , Ismail M , Cash S , Williamson J , Kachur SP , McElroy P , Asamoa K . Pan Afr Med J 2023 46 17 The U.S. Centers for Disease Control and Prevention in collaboration with the National Malaria Elimination Program and the African Field Epidemiology Network established the Malaria Frontline Project to provide innovative approaches to improve the malaria program implementation in Kano and Zamfara States, Nigeria. Innovative approaches such as malaria bulletin, malaria monitoring wall chart, conduct of ward level data validation meetings and malaria dashboard have helped improve the use of data for decision making at all levels. Innovative approaches deployed during the project implementation facilitated data analysis and a better understanding of malaria program performance and data utilization for decision making at all levels. These innovative approaches may improve malaria control program performance in Nigeria and other resource limited countries. © Adefisoye Adewole et al. Pan African Medical Journal (ISSN: 1937-8688). |
More frequent HIV viral load testing with point-of-care tests detects elevated viral load earlier in postpartum HIV-positive women in a randomized controlled trial in two clinics in Johannesburg, South Africa
Fairlie L , Sawry S , Pals S , Sherman G , Williamson D , Le Roux J , Ngeno B , Berrie L , Diallo K , Cox MH , Mogashoa M , Chersich M , Modi S . J Acquir Immune Defic Syndr 2023 94 (5) 412-420 BACKGROUND: Elevated maternal HIV viral load (VL) increases vertical transmission risk for breastfeeding children. This randomized controlled trial in Johannesburg primarily evaluated whether 3-monthly point-of-care testing, with laboratory-based standard-of-care testing (arm 2), compared with 6-monthly laboratory-based VL testing (arm 1) in postpartum women living with HIV receiving first-line tenofovir-emtricitabine-efavirenz antiretroviral treatment improved VL suppression, factors associated with nonsuppression, and drug resistance in those with virologic failure. METHODS: Mother-child pairs were enrolled July 2018-April 2019 at the child's 6/10/14-week clinic visit. Women were randomized 1:1 to arm 1 or 2. Trained staff performed point-of-care VL testing using the Cepheid's Xpert HIV-1 VL assay. We fitted a generalized linear mixed model with VL suppression (<50 copies/mL (cps/mL) and <1000 cps/mL) at enrollment and 6, 12, and 18 months postpartum as the outcome and indicator variables for time, study site, study arm, and interaction variables. The final model tested for a difference by study arm, pooling across time points. RESULTS: Of 405 women enrolled (204 arm 1 and 201 arm 2), 249 (61%) remained in follow-up through 18 months. There was no difference in VL suppression between arms at 6, 12, or 18 months. VL suppression rate (<50 cps/mL) at 18 months was 64.8% in arm 1 and 63.0% in arm 2 (P = 0.27). On bivariate analysis, there was an association with late antenatal booking and being in arm 2 for nonsuppressed VL, but no significant association with breastfeeding. HIV drug resistance was found in 12 of 23 participants (52.2%). CONCLUSION: We found no significant difference in VL suppression with more frequent VL testing in postpartum women living with HIV receiving first-line efavirenz-based antiretroviral treatment. |
Strengthening capacity of health workers to diagnose birth defects in Ugandan hospitals from 2015 to 2021
Namale-Matovu J , Kusolo R , Serunjogi R , Barlow-Mosha L , Mumpe-Mwanja D , Niombi N , Kalibbala D , Williamson D , Valencia D , Moore CA , Mwambi K , Nelson LJ , Namukanja-Mayambala PM , Williams JL , Mai CT , Qi YP , Musoke P . BMC Med Educ 2023 23 (1) 766 BACKGROUND: Limited diagnostic capabilities, resources and health worker skills have deterred the advancement of birth defects surveillance systems in most low- and middle-income countries (LMICs). Empowering health workers to identify and diagnose major external birth defects (BDs) is crucial to establishing effective hospital-based BD surveillance. Makerere University-Johns Hopkins University (MU-JHU) Research Collaboration BD Surveillance System consists of three diagnostic levels: (1) surveillance midwives, (2) MU-JHU clinical team, and (3) U.S. Centers for Disease Control and Prevention (CDC) birth defects subject matter experts (SMEs) who provide confirmatory diagnosis. The diagnostic concordance of major external BDs by surveillance midwives or MU-JHU clinical team with CDC birth defects SMEs were estimated. METHODS: Study staff went through a series of trainings, including birth defects identification and confirmation, before surveillance activities were implemented. To assess the diagnostic concordance, we analyzed surveillance data from 2015 to 2021 for major external BDs: anencephaly, iniencephaly, encephalocele, spina bifida, craniorachischisis, microcephaly, anophthalmia/microphthalmia, anotia/microtia, cleft palate alone, cleft lip alone, cleft lip with cleft palate, imperforate anus, hypospadias, talipes equinovarus, limb reduction, gastroschisis, and omphalocele. Positive predictive value (PPV) as the proportion of BDs diagnosed by surveillance midwives or MU-JHU clinical team that were confirmed by CDC birth defects SMEs was computed. PPVs between 2015 and 2018 and 2019-2021 were compared to assess the accuracy of case diagnosis over time. RESULTS: Of the 204,332 infants examined during 2015-2021, 870 infants had a BD. Among the 1,245 BDs identified, 1,232 (99.0%) were confirmed by CDC birth defects SMEs. For surveillance midwives, PPV for 7 of 17 BDs was > 80%. For the MU-JHU clinical team, PPV for 13 of 17 BDs was > 80%. Among surveillance midwives, PPV improved significantly from 2015 to 2018 to 2019-2021, for microcephaly (+ 50.0%), cleft lip with cleft palate (+ 17.0%), imperforate anus (+ 30.0%), and talipes equinovarus (+ 10.8%). Improvements in PPV were also observed among MU-JHU clinical team; however, none were significant. CONCLUSION: The diagnostic accuracy of the midwives and clinical team increased, highlighting that BD surveillance, by front-line health care workers (midwives) in LMICs is possible when midwives receive comprehensive training, technical support, funding and continuous professional development. |
Developing a prototype pathogen plan and research priorities for the alphaviruses
Powers AM , Williamson LE , Carnahan RH , Crowe JE Jr , Hyde JL , Jonsson CB , Nasar F , Weaver SC . J Infect Dis 2023 228 S414-s426 The Togaviridae family, genus, Alphavirus, includes several mosquito-borne human pathogens with the potential to spread to near pandemic proportions. Most of these are zoonotic, with spillover infections of humans and domestic animals, but a few such as chikungunya virus (CHIKV) have the ability to use humans as amplification hosts for transmission in urban settings and explosive outbreaks. Most alphaviruses cause nonspecific acute febrile illness, with pathogenesis sometimes leading to either encephalitis or arthralgic manifestations with severe and chronic morbidity and occasional mortality. The development of countermeasures, especially against CHIKV and Venezuelan equine encephalitis virus that are major threats, has included vaccines and antibody-based therapeutics that are likely to also be successful for rapid responses with other members of the family. However, further work with these prototypes and other alphavirus pathogens should target better understanding of human tropism and pathogenesis, more comprehensive identification of cellular receptors and entry, and better understanding of structural mechanisms of neutralization. |
Strengthening the reporting of genetic association studies (STREGA): an extension of the strengthening the reporting of observational studies in epidemiology (STROBE) statement.
Little J , Higgins JP , Ioannidis JP , Moher D , Gagnon F , von Elm E , Khoury MJ , Cohen B , Davey-Smith G , Grimshaw J , Scheet P , Gwinn M , Williamson RE , Zou GY , Hutchings K , Johnson CY , Tait V , Wiens M , Golding J , van Duijn C , McLaughlin J , Paterson A , Wells G , Fortier I , Freedman M , Zecevic M , King R , Infante-Rivard C , Stewart AF , Birkett N . J Clin Epidemiol 2009 62 (6) 597-608.e4 Making sense of rapidly evolving evidence on genetic associations is crucial to making genuine advances in human genomics and the eventual integration of this information in the practice of medicine and public health. Assessment of the strengths and weaknesses of this evidence, and hence, the ability to synthesize it, has been limited by inadequate reporting of results. The STrengthening the REporting of Genetic Association (STREGA) studies initiative builds on the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement and provides additions to 12 of the 22 items on the STROBE checklist. The additions concern population stratification, genotyping errors, modeling haplotype variation, Hardy-Weinberg equilibrium, replication, selection of participants, rationale for choice of genes and variants, treatment effects in studying quantitative traits, statistical methods, relatedness, reporting of descriptive and outcome data, and the volume of data issues that are important to consider in genetic association studies. The STREGA recommendations do not prescribe or dictate how a genetic association study should be designed, but seek to enhance the transparency of its reporting, regardless of choices made during design, conduct, or analysis. |
STrengthening the REporting of Genetic Association studies (STREGA): an extension of the STROBE Statement.
Little J , Higgins JP , Ioannidis JP , Moher D , Gagnon F , von Elm E , Khoury MJ , Cohen B , Davey-Smith G , Grimshaw J , Scheet P , Gwinn M , Williamson RE , Zou GY , Hutchings K , Johnson CY , Tait V , Wiens M , Golding J , van Duijn C , McLaughlin J , Paterson A , Wells G , Fortier I , Freedman M , Zecevic M , King R , Infante-Rivard C , Stewart A , Birkett N . Ann Intern Med 2009 150 (3) 206-15 Making sense of rapidly evolving evidence on genetic associations is crucial to making genuine advances in human genomics and the eventual integration of this information into the practice of medicine and public health. Assessment of the strengths and weaknesses of this evidence, and hence the ability to synthesize it, has been limited by inadequate reporting of results. The STrengthening the REporting of Genetic Association studies (STREGA) initiative builds on the STrengthening the Reporting of Observational Studies in Epidemiology (STROBE) Statement and provides additions to 12 of the 22 items on the STROBE checklist. The additions concern population stratification, genotyping errors, modeling haplotype variation, Hardy-Weinberg equilibrium, replication, selection of participants, rationale for choice of genes and variants, treatment effects in studying quantitative traits, statistical methods, relatedness, reporting of descriptive and outcome data, and issues of data volume that are important to consider in genetic association studies. The STREGA recommendations do not prescribe or dictate how a genetic association study should be designed but seek to enhance the transparency of its reporting, regardless of choices made during design, conduct, or analysis. |
Strengthening the reporting of genetic association studies (STREGA): an extension of the STROBE Statement.
Little J , Higgins JP , Ioannidis JP , Moher D , Gagnon F , von Elm E , Khoury MJ , Cohen B , Davey-Smith G , Grimshaw J , Scheet P , Gwinn M , Williamson RE , Zou GY , Hutchings K , Johnson CY , Tait V , Wiens M , Golding J , van Duijn C , McLaughlin J , Paterson A , Wells G , Fortier I , Freedman M , Zecevic M , King R , Infante-Rivard C , Stewart A , Birkett N . Hum Genet 2009 125 (2) 131-51 Making sense of rapidly evolving evidence on genetic associations is crucial to making genuine advances in human genomics and the eventual integration of this information in the practice of medicine and public health. Assessment of the strengths and weaknesses of this evidence, and hence the ability to synthesize it, has been limited by inadequate reporting of results. The STrengthening the REporting of Genetic Association studies (STREGA) initiative builds on the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Statement and provides additions to 12 of the 22 items on the STROBE checklist. The additions concern population stratification, genotyping errors, modeling haplotype variation, Hardy-Weinberg equilibrium, replication, selection of participants, rationale for choice of genes and variants, treatment effects in studying quantitative traits, statistical methods, relatedness, reporting of descriptive and outcome data, and the volume of data issues that are important to consider in genetic association studies. The STREGA recommendations do not prescribe or dictate how a genetic association study should be designed but seek to enhance the transparency of its reporting, regardless of choices made during design, conduct, or analysis. |
STrengthening the REporting of Genetic Association Studies (STREGA): an extension of the STROBE statement.
Little J , Higgins JP , Ioannidis JP , Moher D , Gagnon F , von Elm E , Khoury MJ , Cohen B , Davey-Smith G , Grimshaw J , Scheet P , Gwinn M , Williamson RE , Zou GY , Hutchings K , Johnson CY , Tait V , Wiens M , Golding J , van Duijn C , McLaughlin J , Paterson A , Wells G , Fortier I , Freedman M , Zecevic M , King R , Infante-Rivard C , Stewart A , Birkett N . PLoS Med 2009 6 (2) e22 Making sense of rapidly evolving evidence on genetic associations is crucial to making genuine advances in human genomics and the eventual integration of this information in the practice of medicine and public health. Assessment of the strengths and weaknesses of this evidence, and hence the ability to synthesize it, has been limited by inadequate reporting of results. The STrengthening the REporting of Genetic Association studies (STREGA) initiative builds on the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Statement and provides additions to 12 of the 22 items on the STROBE checklist. The additions concern population stratification, genotyping errors, modelling haplotype variation, Hardy-Weinberg equilibrium, replication, selection of participants, rationale for choice of genes and variants, treatment effects in studying quantitative traits, statistical methods, relatedness, reporting of descriptive and outcome data, and the volume of data issues that are important to consider in genetic association studies. The STREGA recommendations do not prescribe or dictate how a genetic association study should be designed but seek to enhance the transparency of its reporting, regardless of choices made during design, conduct, or analysis. |
Strengthening the reporting of genetic association studies (STREGA): an extension of the STROBE statement.
Little J , Higgins JP , Ioannidis JP , Moher D , Gagnon F , von Elm E , Khoury MJ , Cohen B , Davey-Smith G , Grimshaw J , Scheet P , Gwinn M , Williamson RE , Zou GY , Hutchings K , Johnson CY , Tait V , Wiens M , Golding J , van Duijn C , McLaughlin J , Paterson A , Wells G , Fortier I , Freedman M , Zecevic M , King R , Infante-Rivard C , Stewart A , Birkett N . Eur J Epidemiol 2009 24 (1) 37-55 Making sense of rapidly evolving evidence on genetic associations is crucial to making genuine advances in human genomics and the eventual integration of this information in the practice of medicine and public health. Assessment of the strengths and weaknesses of this evidence, and hence the ability to synthesize it, has been limited by inadequate reporting of results. The STrengthening the REporting of Genetic Association studies (STREGA) initiative builds on the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Statement and provides additions to 12 of the 22 items on the STROBE checklist. The additions concern population stratification, genotyping errors, modeling haplotype variation, Hardy-Weinberg equilibrium, replication, selection of participants, rationale for choice of genes and variants, treatment effects in studying quantitative traits, statistical methods, relatedness, reporting of descriptive and outcome data, and the volume of data issues that are important to consider in genetic association studies. The STREGA recommendations do not prescribe or dictate how a genetic association study should be designed but seek to enhance the transparency of its reporting, regardless of choices made during design, conduct, or analysis. |
STrengthening the REporting of Genetic Association studies (STREGA)--an extension of the STROBE statement.
Little J , Higgins JP , Ioannidis JP , Moher D , Gagnon F , von Elm E , Khoury MJ , Cohen B , Davey-Smith G , Grimshaw J , Scheet P , Gwinn M , Williamson RE , Zou GY , Hutchings K , Johnson CY , Tait V , Wiens M , Golding J , van Duijn C , McLaughlin J , Paterson A , Wells G , Fortier I , Freedman M , Zecevic M , King R , Infante-Rivard C , Stewart A , Birkett N . Eur J Clin Invest 2009 39 (4) 247-66 Making sense of rapidly evolving evidence on genetic associations is crucial to making genuine advances in human genomics and the eventual integration of this information in the practice of medicine and public health. Assessment of the strengths and weaknesses of this evidence, and hence the ability to synthesize it, has been limited by inadequate reporting of results. The STrengthening the REporting of Genetic Association studies (STREGA) initiative builds on the STrengthening the Reporting of OBservational Studies in Epidemiology (STROBE) Statement and provides additions to 12 of the 22 items on the STROBE checklist. The additions concern population stratification, genotyping errors, modelling haplotype variation, Hardy-Weinberg equilibrium, replication, selection of participants, rationale for choice of genes and variants, treatment effects in studying quantitative traits, statistical methods, relatedness, reporting of descriptive and outcome data and the volume of data issues that are important to consider in genetic association studies. The STREGA recommendations do not prescribe or dictate how a genetic association study should be designed, but seek to enhance the transparency of its reporting, regardless of choices made during design, conduct or analysis. |
A model for accelerating access to care and treatment for children and adolescents living with HIV in Nigeria, Tanzania, Uganda, and Zambia: The Faith-Based Action for Scaling-Up Testing and Treatment for the Epidemic Response (FASTER) Initiative
Oliver D , Mabirizi D , Hast M , Alwano MG , Chungu C , Kelemani A , Mbanefo C , Gross J , Parris K , Dowling S , Clark A , Williams A , Simao L , Amole C , Suggu K , Kama J , Mpasela F , Mtui L , Nabitaka V , Saunders R , Williamson D , Rivadeneira ED , Hrapcak S , Nantume S , Nazziwa E , Itoh M , Machage E , Onyenuobi C , Munthali G , Rwebembera A , Mwiya M , Katureebe C , Ikpeazu A , Fenn T . J Int Assoc Provid AIDS Care 2023 22 23259582231186701 The number of children newly infected with HIV dropped by 50%, from 320 000 in 2010 to 160 000 in 2021. Despite progress, ongoing gaps persist in diagnosis, continuity of care, and treatment optimization. In response, the United States President's Emergency Plan for AIDS Relief created the Faith-based Action for Scaling-Up Testing and Treatment for Epidemic Response (FASTER). Faith-based Action for Scaling-Up Testing and Treatment for Epidemic Response addressed gaps in countries with the highest unmet need by working with government to operationalize innovative interventions and ensure alignment with national priorities and with communities living with HIV to ensure the change was community-led. Between 2019 and 2021, FASTER's interventions were incorporated into national policies, absorbed by Ministries of Health, and taken up in subsequent awards and country operating plans. Continued effort is needed to sustain gains made during the FASTER initiative and to continue scaling evidence-based interventions to ensure that children and adolescents are not left behind in the global HIV response. |
Use of U.S. Blood Donors for National Serosurveillance of SARS-CoV-2 Antibodies: Basis for an Expanded National Donor Serosurveillance Program (preprint)
Stone M , Di Germanio C , Wright DJ , Sulaeman H , Dave H , Fink RV , Notari EP , Green V , Strauss D , Kessler D , Destree M , Saa P , Williamson PC , Simmons G , Stramer SL , Opsomer J , Jones JM , Kleinman S , Busch MP . medRxiv 2021 2021.05.01.21255576 Introduction The REDS-IV-P Epidemiology, Surveillance and Preparedness of the Novel SARS-CoV-2 Epidemic (RESPONSE) seroprevalence study conducted monthly cross-sectional testing for SARS-CoV-2 antibodies on blood donors in six U.S. metropolitan regions to estimate the extent of SARS-COV-2 infections over time.Study Design/Methods During March-August 2020, approximately ≥1,000 serum specimens were collected monthly from each region and tested for SARS-CoV-2 antibodies using a well-validated algorithm. Regional seroprevalence estimates were weighted based on demographic differences with the general population. Seroprevalence was compared with reported COVID-19 case rates over time.Results/Findings For all regions, seroprevalence was <1.0% in March 2020. New York experienced the biggest increase (peak seroprevalence, 15.8 % in May). All other regions experienced modest increases in seroprevalence(1-2% in May-June to 2-4% in July-August). Seroprevalence was higher in younger, non-Hispanic Black, and Hispanic donors. Temporal increases in donor seroprevalence correlated with reported case rates in each region. In August, 1.3-5.6 estimated cumulative infections (based on seroprevalence data) per COVID-19 case reported to CDC.Conclusion Increases in seroprevalence were found in all regions, with the largest increase in New York. Seroprevalence was higher in non-Hispanic Black and Hispanic blood donors than in non-Hispanic White blood donors. SARS-CoV-2 antibody testing of blood donor samples can be used to estimate the seroprevalence in the general population by region and demographic group. The methods derived from the RESPONSE seroprevalence study served as the basis for expanding SARS-CoV-2 seroprevalence surveillance to all 50 states and Puerto Rico.Summary SARS-CoV-2 serosurveillance data from blood donors in 6 US regions were used to estimate population weighted seroprevalence. Seroprevelance rates were higher in case rates. The study was expanded to a national donor serosurveillance program.Disclaimer The content is solely the responsibility of the authors and does not represent the policy of the National Institutes of Health or the Department of Health and Human Services. Any specific brandnames included in this manuscript are for identification purposes only and are not intended to represent an endorsement by CDC. The findings and conclusions in this report are those of the authorsand do not necessarily represent the official position of the Centers of Disease Control and Prevention.Competing Interest StatementThe authors have declared no competing interest.Funding StatementThe authors were supported by research contracts from the National Heart, Lung, and Blood Institute (NHLBI Contracts HHSN 75N92019D00032 and HHSN 75N92019D00033) as well as with funding support from the National Institute of Allergies and Infectious Diseases (NIAID), NIH.Author DeclarationsI confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.YesThe details of the IRB/oversight body that provided approval or exemption for the research described are given below:The study was reviewed by the UCSF Committee for Human Research and determined to meet the definition of research as defined in 46.102(l) but did not involve human subjects based on anonymization of data and routine consent for blood donation testing that includes use of residual samples for research purposes (as defined in 46.103(e)(1) consistent with applicable federal law and CDC policy (45 C.F.R. part 46; 21 C.F.R. part 56; 42 U.S.C. p241(d), 5 U.S.C. p552a, 44 U.S.C. p3501)).All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived.YesI understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a pros ective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).YesI have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable.YesThe data is not being made publicly available for privacy reasons related to federal regulations but a limited dataset may be made available upon request after formal review by NHLBI and CDC's privacy office before release. |
Estimating the number of symptomatic SARS-CoV-2 infections among vaccinated individuals in the United States—January–April, 2021 (preprint)
Kugeler KJ , Williamson J , Curns AT , Healy JM , Nolen LD , Clark TA , Martin SW , Fischer M . medRxiv 2021 2021.08.03.21261442 As of March 2021, three COVID-19 vaccines have been authorized by the U.S. Food and Drug Administration (FDA) for use in the United States. Each has substantial efficacy in preventing COVID-19. However, as efficacy from trials was <100% for all three vaccines, disease in vaccinated people is expected to occur. We created a spreadsheet-based tool to estimate the number of symptomatic vaccine breakthrough infections based on published vaccine efficacy (VE) data, percent of the population that has been fully vaccinated, and average number of COVID-19 cases reported per day. We estimate that approximately 51,000 symptomatic vaccine breakthrough infections (95% CI: ∼48,000–55,000 cases) occurred in the United States during January–April 2021 among >77 million fully vaccinated people, reflecting <0.5% of COVID-19 cases that occurred during that time. With ongoing SARS-CoV-2 transmission and increasing numbers of people vaccinated in the United States, vaccine breakthrough infections will continue to accumulate before population immunity is sufficient to interrupt transmission. Understanding expectations regarding number of vaccine breakthrough infections enables accurate public health messaging to help ensure that the occurrence of such cases does not negatively affect vaccine perceptions, confidence, and uptake.Competing Interest StatementThe authors have declared no competing interest.Funding StatementNo external funding was received.Author DeclarationsI confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.YesThe details of the IRB/oversight body that provided approval or exemption for the research described are given below:This activity was conducted consistent with applicable federal policy.All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived.YesI understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).YesI have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable.YesAll input data are publicly available |
Divergent lineages of pathogenic Leptospira species are widespread and persisting in the environment in Puerto Rico, USA (preprint)
Stone NE , Hall CM , Ortiz M , Hutton S , Santana-Propper E , Celona KR , Williamson CHD , Bratsch N , Fernandes LGV , Busch JD , Pearson T , Rivera-Garcia S , Soltero F , Galloway R , Sahl JW , Nally JE , Wagner DM . medRxiv 2021 11 Background: Leptospirosis, caused by Leptospira bacteria, is a common zoonosis worldwide more prevalent in the tropics. Reservoir species and risk factors have been identified but surveys for environmental sources of leptospirosis are rare. Furthermore, understanding of environmental Leptospira containing pathogenic genes and possibly capable of causing disease is incomplete and could result in some pathogenic strains evading detection, thereby convoluting diagnosis, prevention, and epidemiology. Methodology/Principal Findings: We collected environmental samples from 22 sites in Puerto Rico during three sampling periods over 14-months (Dec 2018-Feb 2020); 10 water and 10 soil samples were collected at each site. Samples were screened for pathogenic Leptospira DNA using the lipL32 PCR assay and positive samples were sequenced to assess genetic diversity. One urban site in San Juan was sampled three times over 14 months to assess persistence in soil; live leptospires were obtained during the last sampling period. Isolates were whole genome sequenced and LipL32 expression was assessed in vitro. We detected pathogenic Leptospira DNA at 15/22 sites; both soil and water were positive at 5/15 sites. We recovered lipL32 sequences from 83/86 positive samples (15/15 positive sites) and secY sequences from 32/86 (10/15 sites); multiple genotypes were identified at 12 sites. These sequences revealed significant diversity across samples, including four novel lipL32 phylogenetic clades. Most samples from the serially sampled site were lipL32 positive at each time point. We sequenced the genomes of six saprophytic and two pathogenic Leptospira isolates; the latter represent a novel pathogenic Leptospira species likely belonging to a new serogroup. Conclusions/Significance: Diverse and novel pathogenic Leptospira are widespread in the environment in Puerto Rico. The disease potential of the novel lineages is unknown but several persisted for >1 year in soil, which could contaminate water. This work increases understanding of environmental Leptospira and should improve leptospirosis surveillance and diagnostics. 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. |
Self-Reported Mask Use among Persons with or without SARS CoV-2 Vaccination -United States, December 2020-August 2021 (preprint)
Calamari LE , Weintraub WS , Santos R , Gibbs M , Bertoni AG , Ward LM , Saydah S , Plumb ID , Runyon MS , Wierzba TF , Sanders JW , Herrington D , Espeland MA , Williamson J , Mongraw-Chaffin M , Bertoni A , Alexander-Miller MA , Castri P , Mathews A , Munawar I , Seals AL , Ostasiewski B , Ballard CAP , Gurcan M , Ivanov A , Zapata GM , Westcott M , Blinson K , Blinson L , Mistysyn M , Davis D , Doomy L , Henderson P , Jessup A , Lane K , Levine B , McCanless J , McDaniel S , Melius K , O'Neill C , Pack A , Rathee R , Rushing S , Sheets J , Soots S , Wall M , Wheeler S , White J , Wilkerson L , Wilson R , Wilson K , Burcombe D , Saylor G , Lunn M , Ordonez K , O'Steen A , Wagner L , McCurdy LH , Gibbs MA , Taylor YJ , Calamari L , Tapp H , Ahmed A , Brennan M , Munn L , Dantuluri KL , Hetherington T , Lu LC , Dunn C , Hogg M , Price A , Leonidas M , Manning M , Rossman W , Gohs FX , Harris A , Priem JS , Tochiki P , Wellinsky N , Silva C , Ludden T , Hernandez J , Spencer K , McAlister L , Weintraub W , Miller K , Washington C , Moses A , Dolman S , Zelaya-Portillo J , Erkus J , Blumenthal J , Romero Barrientos RE , Bennett S , Shah S , Mathur S , Boxley C , Kolm P , Franklin E , Ahmed N , Larsen M , Oberhelman R , Keating J , Kissinger P , Schieffelin J , Yukich J , Beron A , Teigen J , Kotloff K , Chen WH , Friedman-Klabanoff D , Berry AA , Powell H , Roane L , Datar R , Correa A , Navalkele B , Min YI , Castillo A , Ward L , Santos RP , Anugu P , Gao Y , Green J , Sandlin R , Moore D , Drake L , Horton D , Johnson KL , Stover M , Lagarde WH , Daniel L , Maguire PD , Hanlon CL , McFayden L , Rigo I , Hines K , Smith L , Harris M , Lissor B , Cook V , Eversole M , Herrin T , Murphy D , Kinney L , Diehl P , Abromitis N , Pierre TSt , Heckman B , Evans D , March J , Whitlock B , Moore W , Arthur S , Conway J , Gallaher TR , Johanson M , Brown S , Dixon T , Reavis M , Henderson S , Zimmer M , Oliver D , Jackson K , Menon M , Bishop B , Roeth R , King-Thiele R , Hamrick TS , Ihmeidan A , Hinkelman A , Okafor C , Bray Brown RB , Brewster A , Bouyi D , Lamont K , Yoshinaga K , Vinod P , Peela AS , Denbel G , Lo J , Mayet-Khan M , Mittal A , Motwani R , Raafat M , Schultz E , Joseph A , Parkeh A , Patel D , Afridi B , Uschner D , Edelstein SL , Santacatterina M , Strylewicz G , Burke B , Gunaratne M , Turney M , Zhou SQ , Tjaden AH , Fette L , Buahin A , Bott M , Graziani S , Soni A , Mores C , Porzucek A , Laborde R , Acharya P , Guill L , Lamphier D , Schaefer A , Satterwhite WM , McKeague A , Ward J , Naranjo DP , Darko N , Castellon K , Brink R , Shehzad H , Kuprianov D , McGlasson D , Hayes D , Edwards S , Daphnis S , Todd B , Goodwin A , Berkelman R , Hanson K , Zeger S , Hopkins J , Reilly C , Edwards K , Gayle H , Redd S . medRxiv 2022 10 Wearing a facemask can help to decrease the transmission of COVID-19. We investigated self-reported mask use among subjects aged 18 years and older participating in the COVID-19 Community Research Partnership (CRP), a prospective longitudinal COVID-19 surveillance study in the mid-Atlantic and southeastern United States. We included those participants who completed >=5 daily surveys each month from December 1, 2020 through August 31, 2021. Mask use was defined as self-reported use of a face mask or face covering on every interaction with others outside the household within a distance of less than 6 feet. Participants were considered vaccinated if they reported receiving >=1 COVID-19 vaccine dose. Participants (n=17,522) were 91% non-Hispanic White, 68% female, median age 57 years, 26% healthcare workers, with 95% self-reported receiving >=1 COVID-19 vaccine dose through August; mean daily survey response was 85%. Mask use was higher among vaccinated than unvaccinated participants across the study period, regardless of the month of the first dose. Mask use remained relatively stable from December 2020 through April (range 71-80% unvaccinated; 86-93% vaccinated) and declined in both groups beginning in mid-May 2021 to 34% and 42% respectively in June 2021; mask use has increased again since July 2021. Mask use by all was lower during weekends and on Christmas and Easter, regardless of vaccination status. Independent predictors of higher mask use were vaccination, age >=65 years, female sex, racial or ethnic minority group, and healthcare worker occupation, whereas a history of self-reported prior COVID-19 illness was associated with lower use. Copyright The copyright holder for this preprint is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. This article is a US Government work. It is not subject to copyright under 17 USC 105 and is also made available for use under a CC0 license. |
Sensitivity and Uncertainty Analysis for Two-Stream Capture-Recapture Methods in Disease Surveillance (preprint)
Zhang Y , Chen J , Ge L , Williamson JM , Waller LA , Lyles RH . medRxiv 2022 23 Capture-recapture methods are widely applied in estimating the number (N) of prevalent or cumulatively incident cases in disease surveillance. Here, we focus the bulk of our attention on the common case in which there are two data streams. We propose a sensitivity and uncertainty analysis framework grounded in multinomial distribution-based maximum likelihood, hinging on a key dependence parameter that is typically non-identifiable but is epidemiologically interpretable. Focusing on the epidemiologically meaningful parameter unlocks appealing data visualizations for sensitivity analysis and provides an intuitively accessible framework for uncertainty analysis designed to leverage the practicing epidemiologist's understanding of the implementation of the surveillance streams as the basis for assumptions driving estimation of N. By illustrating the proposed sensitivity analysis using publicly available HIV surveillance data, we emphasize both the need to admit the lack of information in the observed data and the appeal of incorporating expert opinion about the key dependence parameter. The proposed uncertainty analysis is an empirical Bayes-like approach designed to more realistically acknowledge variability in the estimated N associated with uncertainty in an expert's opinion about the non-identifiable parameter, together with the statistical uncertainty. We demonstrate how such an approach can also facilitate an appealing general interval estimation procedure to accompany capture-recapture methods. Simulation studies illustrate the reliable performance of the proposed approach for quantifying uncertainties in estimating N in various contexts. Finally, we demonstrate how the recommended paradigm has the potential to be directly extended for application to data from more than two surveillance streams. 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. |
Late remdesivir treatment initiation partially protects African green monkeys from lethal Nipah virus infection
de Wit E , Williamson BN , Feldmann F , Goldin K , Lo MK , Okumura A , Lovaglio J , Bunyan E , Porter DP , Cihlar T , Saturday G , Spiropoulou CF , Feldmann H . Antiviral Res 2023 216 105658 Remdesivir is a nucleotide prodrug with preclinical efficacy against lethal Nipah virus infection in African green monkeys when administered 1 day post inoculation (dpi) (Lo et al., 2019). Here, we determined whether remdesivir treatment was still effective when treatment administration initiation was delayed until 3 dpi. Three groups of six African green monkeys were inoculated with a lethal dose of Nipah virus, genotype Bangladesh. On 3 dpi, one group received a loading dose of 10 mg/kg remdesivir followed by daily dosing with 5 mg/kg for 11 days, one group received 10 mg/kg on 12 consecutive days, and the remaining group received an equivalent volume of vehicle solution. Remdesivir treatment initiation on 3 dpi provided partial protection from severe Nipah virus disease that was dose dependent, with 67% of animals in the high dose group surviving the challenge. However, remdesivir treatment did not prevent clinical disease, and surviving animals showed histologic lesions in the brain. Thus, early administration seems critical for effective remdesivir treatment during Nipah virus infection. |
Notes from the field: Exposures to mpox among cases in children aged 12 years - United States, September 25-December 31, 2022
Nemechek K , Stefanos R , Miller EL , Riser A , Kebede B , Galang RR , Hufstetler K , Descamps D , Balenger A , Hennessee I , Neelam V , Hutchins HJ , Labuda SM , Davis KM , McCormick DW , Marx GE , Kimball A , Ruberto I , Williamson T , Rzucidlo P , Willut C , Harold RE , Mangla AT , English A , Brikshavana D , Blanding J , Kim M , Finn LE , Marutani A , Lockwood M , Johnson S , Ditto N , Wilton S , Edmond T , Stokich D , Shinall A , Alravez B , Crawley A , Nambiar A , Gateley EL , Schuman J , White SL , Davis K , Milleron R , Mendez M , Kawakami V , Segaloff HE , Bower WA , Ellington SR , McCollum AM , Pao LZ . MMWR Morb Mortal Wkly Rep 2023 72 (23) 633-635 During May 17–December 31, 2022, 125 probable or confirmed U.S. monkeypox (mpox)† cases were reported among patients aged <18 years, including 45 (36%) in children aged ≤12 years. Eighty-three cases in persons aged <18 years diagnosed during May 17–September 24, 2022 were previously described (1); 28 (34%) of these were in children aged ≤12 years, 29% of whom did not have reported information on exposure. Among 20 (71%) of 28 patients with documented information on exposure, most were exposed by a household contact. This report updates the previous report using data collected during September 25–December 31, 2022, proposes possible mpox exposure routes in children aged ≤12 years, and describes three U.S. mpox cases in neonates. Household members or caregivers with mpox, including pregnant women and their health care providers, should be informed of the risk of transmission to persons aged <18 years, and strategies to protect persons aged <18 years at risk for exposure, including isolating household contacts with mpox, should be implemented immediately. | | During September 25–December 31, 2022, 17 children aged ≤12 years with probable or confirmed mpox were identified through national surveillance. CDC provided a questionnaire to state and local health departments for collection of the child’s history of exposure to any person with mpox§ during the previous 3 weeks, exposure settings, types of contact (e.g., skin-to-skin, being held or cuddled, diaper change, or toilet use), and precautions taken by the person with mpox (e.g., practiced isolation or covered lesions). This activity was reviewed by CDC and was conducted consistent with applicable federal law and CDC policy.¶ |
Spatial clustering and risk factors for malaria infections and marker of recent exposure to plasmodium falciparum from a household survey in Artibonite, Haiti
Hamre KES , Dismer AM , Rogier E , van den Hoogen LL , Williamson J , Kishore N , Travers A , McGee K , Pierre B , Fouché B , Impoinvil D , Holmes K , Stresman G , Druetz T , Eisele TP , Drakeley C , Lemoine JF , Chang MA . Am J Trop Med Hyg 2023 109 (2) 258-272 Targeting malaria interventions in elimination settings where transmission is heterogeneous is essential to ensure the efficient use of resources. Identifying the most important risk factors among persons experiencing a range of exposure can facilitate such targeting. A cross-sectional household survey was conducted in Artibonite, Haiti, to identify and characterize spatial clustering of malaria infections. Household members (N = 21,813) from 6,962 households were surveyed and tested for malaria. An infection was defined as testing positive for Plasmodium falciparum by either a conventional or novel highly sensitive rapid diagnostic test. Seropositivity to the early transcribed membrane protein 5 antigen 1 represented recent exposure to P. falciparum. Clusters were identified using SaTScan. Associations among individual, household, and environmental risk factors for malaria, recent exposure, and living in spatial clusters of these outcomes were evaluated. Malaria infection was detected in 161 individuals (median age: 15 years). Weighted malaria prevalence was low (0.56%; 95% CI: 0.45-0.70%). Serological evidence of recent exposure was detected in 1,134 individuals. Bed net use, household wealth, and elevation were protective, whereas being febrile, over age 5 years, and living in either households with rudimentary wall material or farther from the road increased the odds of malaria. Two predominant overlapping spatial clusters of infection and recent exposure were identified. Individual, household, and environmental risk factors are associated with the odds of individual risk and recent exposure in Artibonite; spatial clusters are primarily associated with household-level risk factors. Findings from serology testing can further strengthen the targeting of interventions. |
Quantification of SARS-CoV-2 spike protein expression from mRNA vaccines using isotope dilution mass spectrometry
Sutton WJH , Branham PJ , Williamson YM , Cooper HC , Najjar FN , Pierce-Ruiz CL , Barr JR , Williams TL . Vaccine 2023 The advent of mRNA vaccine technology has been vital in rapidly creating and manufacturing COVID-19 vaccines at an industrial scale. To continue to accelerate this leading vaccine technology, an accurate method is needed to quantify antigens produced by the transfection of cells with a mRNA vaccine product. This will allow monitoring of protein expression during mRNA vaccine development and provide information on how changes to vaccine components affects the expression of the desired antigen. Developing novel approaches that allow for high-throughput screening of vaccines to detect changes in antigen production in cell culture prior to in vivo studies could aid vaccine development. We have developed and optimized an isotope dilution mass spectrometry method to detect and quantify the spike protein expressed after transfection of baby hamster kidney cells with expired COVID-19 mRNA vaccines. Five peptides of the spike protein are simultaneously quantified and provide assurance that protein digestion in the region of the target peptides is complete since results between the five peptides had a relative standard deviation of less than 15 %. In addition, two housekeeping proteins, actin and GAPDH, are quantified in the same analytical run to account for any variation in cell growth within the experiment. IDMS allows a precise and accurate means to quantify protein expression by mammalian cells transfected with an mRNA vaccine. |
Acceptability, feasibility, drug safety, and effectiveness of a pilot mass drug administration with a single round of sulfadoxine-pyrimethamine plus primaquine and indoor residual spraying in communities with malaria transmission in Haiti, 2018
Chang MA , Impoinvil D , Hamre KES , Dalexis PE , Mérilien JB , Dismer AM , Fouché B , Desir L , Holmes K , Lafortune W , Herman C , Rogier E , Noland GS , Young AJ , Druetz T , Ashton R , Eisele TP , Cohen J , van den Hoogen L , Stresman G , Drakeley C , Pothin E , Cameron E , Battle KE , Williamson J , Telfort MA , Lemoine JF . Am J Trop Med Hyg 2023 108 (6) 1127-1139 For a malaria elimination strategy, Haiti's National Malaria Control Program piloted a mass drug administration (MDA) with indoor residual spraying (IRS) in 12 high-transmission areas across five communes after implementing community case management and strengthened surveillance. The MDA distributed sulfadoxine-pyrimethamine and single low-dose primaquine to eligible residents during house visits. The IRS campaign applied pirimiphos-methyl insecticide on walls of eligible houses. Pre- and post-campaign cross-sectional surveys were conducted to assess acceptability, feasibility, drug safety, and effectiveness of the combined interventions. Stated acceptability for MDA before the campaign was 99.2%; MDA coverage estimated at 10 weeks post-campaign was 89.6%. Similarly, stated acceptability of IRS at baseline was 99.9%; however, household IRS coverage was 48.9% because of the high number of ineligible houses. Effectiveness measured by Plasmodium falciparum prevalence at baseline and 10 weeks post-campaign were similar: 1.31% versus 1.43%, respectively. Prevalence of serological markers were similar at 10 weeks post-campaign compared with baseline, and increased at 6 months. No severe adverse events associated with the MDA were identified in the pilot; there were severe adverse events in a separate, subsequent campaign. Both MDA and IRS are acceptable and feasible interventions in Haiti. Although a significant impact of a single round of MDA/IRS on malaria transmission was not found using a standard pre- and post-intervention comparison, it is possible there was blunting of the peak transmission. Seasonal malaria transmission patterns, suboptimal IRS coverage, and low baseline parasitemia may have limited the effectiveness or the ability to measure effectiveness. |
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. |
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