Last data update: Apr 18, 2025. (Total: 49119 publications since 2009)
Records 1-30 (of 72 Records) |
Query Trace: Pearce N[original query] |
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Antibody response to symptomatic infection with SARS-CoV-2 omicron variant viruses, December 2021-June 2022
Sandford R , Yadav R , Noble EK , Sumner K , Joshi D , Tartof SY , Wernli KJ , Martin ET , Gaglani M , Zimmerman RK , Talbot HK , Grijalva CG , Belongia EA , Carlson C , Coughlin M , Flannery B , Pearce B , Rogier E . Influenza Other Respir Viruses 2024 18 (7) e13339 ![]() We describe humoral immune responses in 105 ambulatory patients with laboratory-confirmed SARS-CoV-2 Omicron variant infection. In dried blood spot (DBS) collected within 5 days of illness onset and during convalescence, we measured binding antibody (bAb) against ancestral spike protein receptor binding domain (RBD) and nucleocapsid (N) protein using a commercial multiplex bead assay. Geometric mean bAb concentrations against RBD increased by a factor of 2.5 from 1258 to 3189 units/mL and by a factor of 47 against N protein from 5.5 to 259 units/mL between acute illness and convalescence; lower concentrations were associated with greater geometric mean ratios. Paired DBS specimens may be used to evaluate humoral response to SARS-CoV-2 infection. |
Association of infection with Toxoplasma gondii and Toxocara on cognitive function among US adults aged 60 and over, NHANES 2011-2014
Kruszon-Moran D , Brody D , Pearce B . J Epidemiol Community Health 2023 77 (5) 315-321 BACKGROUND: Toxoplasma gondii and Toxocara are common parasites that infect humans globally. Our aim was to examine the relationship between T. gondii and Toxocara infection and cognition. METHODS: Multivariate logistic regression was used to test the association of T. gondii and Toxocara seropositivity on indices of cognitive function (a word list learning trial with delayed recall from the Consortium to Establish a Registry for Alzheimer's Disease, an animal fluency test (AFT) and a digit symbol substitution test (DSST)) among 2643 adults aged 60 years and older in the 2011-2014 National Health and Nutrition Examination Survey. RESULTS: Seropositivity to T. gondii or Toxocara were both associated with lower scores in all three cognitive function measures examined in univariate analyses. Except for the DSST, these associations were not significant after adjustment for age, gender, race and Hispanic origin, poverty level, education, US birth status, depression and hypertension. On stratification to account for significant interactions, Toxocara seropositivity was associated with worse scores on the AFT among those born outside the USA, worse scores on the DSST among those aged 60-69 years, female, Hispanic and with a high school diploma or less. Lower DSST scores with Toxocara infection was greater for adults living below compared with at or above the poverty level. CONCLUSIONS: Seropositivity to these parasites, particularly to Toxocara, may be associated with diminished cognitive performance in certain subgroups of older adults. |
Strategies to reduce harm: An expert panel discussion on the fentanyl crisis
Leitz SJ , Bagley SM , Cook AJ , Jones C , Lawrence D , Pearce P . Perm J 2023 27 (1) 1-13 According to provisional data from the Centers for Disease Control and Prevention (CDC), during the 12-month period ending in July 2022, an estimated 107,500 1 lives were lost to a drug overdose. More than 81,000 of the overdose deaths involved opioids. These numbers represent people who were mothers, fathers, daughters, sons, husbands, wives, brothers, sisters, classmates, teammates, and best friends. The effects of these losses have cascaded through all aspects of our communities and across generations. To highlight the crisis and provide understanding and strategies to prevent the further loss of life, we have brought together a panel of experts with a wide range of knowledge and experience, from patient advocacy and prevention to front-line work to federal policy, from across the United States, to discuss the nationwide fentanyl crisis. |
An evaluation of the species and subspecies of the genus Salmonella with whole genome sequence data: Proposal of type strains and epithets for novel S. enterica subspecies VII, VIII, IX, X and XI.
Pearce ME , Langridge GC , Lauer AC , Grant K , Maiden MCJ , Chattaway MA . Genomics 2021 113 (5) 3152-3162 ![]() ![]() Species and subspecies within the Salmonella genus have been defined for public health purposes by biochemical properties; however, reference laboratories have increasingly adopted sequence-based, and especially whole genome sequence (WGS), methods for surveillance and routine identification. This leads to potential disparities in subspecies definitions, routine typing, and the ability to detect novel subspecies. A large-scale analysis of WGS data from the routine sequencing of clinical isolates was employed to define and characterise Salmonella subspecies population structure, demonstrating that the Salmonella species and subspecies were genetically distinct, including those previously identified through phylogenetic approaches, namely: S. enterica subspecies londinensis (VII), subspecies brasiliensis (VIII), subspecies hibernicus (IX), and subspecies essexiensis (X). The analysis also identified an additional novel subspecies, reptilium (XI). Further, these analyses indicated that S. enterica subspecies IIIa isolates were divergent from the other S. enterica subspecies, which clustered together and, on the basis of ANI analysis, subspecies IIIa was sufficiently distinct to be classified as a separate species, S. arizonae. Multiple phylogenetic and statistical approaches generated congruent results, suggesting that the proposed species and subspecies structure was sufficiently biologically robust for routine application. Biochemical analyses demonstrated that not all subspecies were distinguishable by these means and that biochemical approaches did not capture the genomic diversity of the genus. We recommend the adoption of standardised genomic definitions of species and subspecies and a genome sequence-based approach to routine typing for the identification and definition of novel subspecies. |
Intranasal powder live attenuated influenza vaccine is thermostable, immunogenic, and protective against homologous challenge in ferrets
Luczo JM , Bousse T , Johnson SK , Jones CA , Pearce N , Neiswanger CA , Wang MX , Miller EA , Petrovsky N , Wentworth DE , Bronshtein V , Papania M , Tompkins SM . NPJ Vaccines 2021 6 (1) 59 Influenza viruses cause annual seasonal epidemics and sporadic pandemics; vaccination is the most effective countermeasure. Intranasal live attenuated influenza vaccines (LAIVs) are needle-free, mimic the natural route of infection, and elicit robust immunity. However, some LAIVs require reconstitution and cold-chain requirements restrict storage and distribution of all influenza vaccines. We generated a dry-powder, thermostable LAIV (T-LAIV) using Preservation by Vaporization technology and assessed the stability, immunogenicity, and efficacy of T-LAIV alone or combined with delta inulin adjuvant (Advax™) in ferrets. Stability assays demonstrated minimal loss of T-LAIV titer when stored at 25 °C for 1 year. Vaccination of ferrets with T-LAIV alone or with delta inulin adjuvant elicited mucosal antibody and robust serum HI responses in ferrets, and was protective against homologous challenge. These results suggest that the Preservation by Vaporization-generated dry-powder vaccines could be distributed without refrigeration and administered without reconstitution or injection. Given these significant advantages for vaccine distribution and delivery, further research is warranted. |
Toxicological analysis of aerosols derived from three electronic nicotine delivery systems using Normal human bronchial epithelial cells
Pearce K , Gray N , Gaur P , Jeon J , Suarez A , Shannahan J , Pappas RS , Wright C . Toxicol In Vitro 2020 69 104997 Electronic nicotine delivery systems (ENDS) are a rapidly growing global market advertised as a safer alternative to combustible cigarettes. However, comprehensive investigations of END aerosol physicochemical and toxicological properties have not been fully explored across brands to assess relative safety. In this study, we evaluated aerosols collected from three ENDS - Juul Fruit Medley (5% nicotine), Logic Power (2.4% nicotine), and Mistic (1.8% nicotine). ENDS aerosols were generated using standard machine puffing regimen and collected with a novel fluoropolymer condensation trap. Triple quadrupole-inductively coupled plasma-mass determined the presence of heavy metals in collected aerosols. The toxicological effects of ENDS aerosols on normal human bronchial epithelial cells (NHBE) were investigated using cellular viability, reactive oxygen species, oxidative stress assays, along with DNA damage assessments using the CometChip©. Results indicated the total metal concentrations within collected ENDS aerosols were higher for Mistic and Logic compared to Juul. Logic Power aerosols elicited higher reactive oxygen species levels than Mistic and Juul in NHBE after 24-h exposure. Similar dose-dependent reductions of cellular viability and total glutathione were found for each exposure. However, Logic and Juul aerosols caused greater single stranded DNA damage compared to Mistic. Our study indicates that regardless of brand, ENDS aerosols are toxic to upper airway epithelial cells and may pose a potential respiratory hazard to occasional and frequent users. |
Prenatal exposure to per- and polyfluoroalkyl substances and maternal and neonatal thyroid function in the Project Viva Cohort: A mixtures approach
Preston EV , Webster TF , Claus Henn B , McClean MD , Gennings C , Oken E , Rifas-Shiman SL , Pearce EN , Calafat AM , Fleisch AF , Sagiv SK . Environ Int 2020 139 105728 ![]() BACKGROUND: Maternal and neonatal thyroid function is critical for growth and neurodevelopment. Exposure to individual per- and polyfluoroalkyl substances (PFAS) can alter circulating thyroid hormone levels, but few studies have investigated effects of combined exposure to multiple PFAS. OBJECTIVES: Estimate associations of exposure to multiple PFAS during early pregnancy with maternal and neonatal thyroid function. METHODS: The study population consisted of 726 mothers and 465 neonates from Project Viva, a Boston, Massachusetts area longitudinal pre-birth cohort. We measured six PFAS [perfluorooctanoate (PFOA), perfluorooctane sulfonate (PFOS), perfluorononanoate (PFNA), perfluorohexane sulfonate (PFHxS), 2-(N-ethyl-perfluorooctane sulfonamido)acetate (EtFOSAA), and 2-(N-methyl-perfluorooctane sulfonamido)acetate (MeFOSAA)] and thyroxine (T4), Free T4 Index (FT4I), and thyroid stimulating hormone (TSH) in maternal plasma samples collected during early pregnancy, and neonatal T4 in postpartum heel sticks. We estimated individual and joint effects of PFAS exposure with thyroid hormone levels using weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR), and evaluated potential non-linearity and interactions among PFAS using BKMR. RESULTS: Higher concentrations of the PFAS mixture were associated with significantly lower maternal FT4I, with MeFOSAA, EtFOSAA, PFOA, and PFHxS contributing most to the overall mixture effect in BKMR and WQS regression. In infants, higher concentrations of the PFAS mixture were associated with lower T4 levels, primarily in males, with PFHxS and MeFOSAA contributing most in WQS, and PFHxS contributing most in BKMR. The PFAS mixture was not associated with maternal T4 or TSH levels. However, in maternal BKMR analyses, ln-PFOS was positively associated with T4 levels (Delta25(th) to 75th percentile: 0.21 microg/dL; 95% credible interval: -0.03, 0.47) and ln-PFHxS was associated with a non-linear effect on TSH levels. CONCLUSIONS: These findings support the hypothesis that there may be combined effects of prenatal exposure to multiple PFAS on maternal and neonatal thyroid function, but the direction and magnitude of these effects may vary across individual PFAS. |
Evaluation of A(H1N1)pdm09 LAIV vaccine candidates stability and replication efficiency in primary human nasal epithelial cells
Shcherbik S , Pearce N , Carney P , Bazhenova E , Larionova N , Kiseleva I , Rudenko L , Kumar A , Goldsmith CS , Dugan V , Stevens J , Wentworth DE , Bousse T . Vaccine: X 2019 2 100031 The recent reduction of live attenuated influenza vaccine (LAIV) effectiveness in multivalent formulations was particularly associated with the A(H1N1)pdm09 component. In the 2017 the WHO vaccine composition committee changed its recommendations for the A(H1N1)pdm09 component to include an A/Michigan/45/2015-like virus. We evaluated effectiveness and quality of newly developed and previous A(H1N1)pdm09 LAIV reassortants through assessment of their thermal and pH stability, receptor binding specificity and replication fitness in primary human airway epithelial cells of nasal origin (hAECN). Our analysis showed that LAIV expressed hemagglutinin (HA) and neuraminidase (NA) from an A/Michigan/45/2015-like strain A/New York/61/2015 (A/New York/61/2015-CDC-LV16A, NY-LV16A), exhibit higher thermal and pH stability compared to the previous vaccine candidates expressing HA and NA from A/California/07/2009 and A/Bolivia/559/2013 (A17/Cal09 and A17/Bol13). Reassortants A/South Africa/3626/2013-CDC-LV14A (SA-LV14A) and NY-LV16A showed preferential binding to alpha2,6 sialic acid (SA) receptors and replicated at higher titers and more extensively in hAECN compared to A17/Cal09 and A17/Bol13, which had an alpha2,3 SA receptor binding preference. Our data analysis supports selection of A/New York/61/2015-CDC-LV16A for LAIV formulation and the introduction of new assays for LAIV characterization. |
Hypertensive disorders in pregnancy and maternal and neonatal outcomes in Haiti: the importance of surveillance and data collection
Bridwell M , Handzel E , Hynes M , Jean-Louis R , Fitter D , Hogue C , Grand-Pierre R , Pierre H , Pearce B . BMC Pregnancy Childbirth 2019 19 (1) 208 BACKGROUND: This study aims to determine reported prevalence of hypertensive disorders in pregnancy (HDP) and maternal and neonatal outcomes associated with these disorders among women delivering at selected hospitals across Haiti. METHODS: A retrospective review of 8822 singleton deliveries between January 2012 and December 2014 was conducted at four hospitals in separate Departments across Haiti. Researchers examined the proportion of women with reported HDP (hypertension, preeclampsia, eclampsia) and the association between women with HDP and three neonatal outcomes: low birth weight, preterm birth, and stillbirths; and two maternal outcomes: placental abruption and maternal death in Hopital Albert Schweitzer (HAS). Odds ratios for associations between HDP and perinatal outcomes at HAS were assessed using logistic regression, adjusting for potential confounders. RESULTS: Of the 8822 singleton births included in the study, 510 (5.8%) had a reported HDP (including 285 (55.9%) preeclampsia, 119 (23.3%) eclampsia, and 106 (20.8%) hypertension). Prevalence of HDP among each hospital was: HAS (13.5%), Hopital Immaculee Conception des Cayes (HIC) (3.2%), Fort Liberte (4.3%), and Hopital Sacre Coeur de Milot (HSC) (3.0%). Among women at HAS with HDP, the adjusted odds of having a low birth weight baby was four times that of women without HDP (aOR 4.17, 95% CI 3.19-5.45), more than three times that for stillbirths (aOR 3.51, 95% CI 2.43-5.06), and five times as likely to result in maternal death (aOR 5.13, 95% CI 1.53-17.25). Among the three types of HDP, eclampsia was associated with the greatest odds of adverse events with five times the odds of having a low birth weight baby (aOR 5.00, 95% CI 2.84-8.79), six times the odds for stillbirths (aOR 6.34, 95% CI 3.40-11.82), and more than twelve times as likely to result in maternal death (aOR 12.70, 95% CI 2.33-69.31). CONCLUSIONS: A high prevalence of HDP was found among a cohort of Haitian mothers. HDP was associated with higher rates of adverse maternal and neonatal outcomes in HAS, which is comparable to studies of HDP conducted in high-income countries. |
Monoclonal antibody against N2 neuraminidase of cold adapted A/Leningrad/134/17/57 (H2N2) enables efficient generation of live attenuated influenza vaccines
Shcherbik S , Carney P , Pearce N , Stevens J , Dugan VG , Wentworth DE , Bousse T . Virology 2018 522 65-72 Cold adapted influenza virus A/Leningrad/134/17/57 (H2N2) is a reliable master donor virus (Len/17-MDV) for preparing live attenuated influenza vaccines (LAIV). LAIVs are 6:2 reasortants that contain 6 segments of Len/17-MDV and the hemagglutinin (HA) and neuraminidase (NA) of contemporary circulating influenza A viruses. The problem with the classical reassortment procedure used to generate LAIVs is that there is limited selection pressure against NA of the Len/17-MDV resulting in 7:1 reassortants with desired HA only, which are not suitable LAIVs. The monoclonal antibodies (mAb) directed against the N2 of Len/17-MDV were generated. 10C4-8E7 mAb inhibits cell-to-cell spread of viruses containing the Len/17-MDV N2, but not viruses with the related N2 from contemporary H3N2 viruses. 10C4-8E7 antibody specifically inhibited the Len/17-MDV replication in vitro and in ovo but didn't inhibit replication of H3N2 or H1N1pdm09 reassortants. Our data demonstrate that addition of 10C4-8E7 in the classical reassortment improves efficiency of LAIV production. |
Pathogenesis and transmission of genetically diverse swine-origin H3N2v influenza A viruses from multiple lineages isolated in the United States, 2011-2016.
Sun X , Pulit-Penaloza JA , Belser JA , Pappas C , Pearce MB , Brock N , Zeng H , Creager HM , Zanders N , Jang Y , Tumpey TM , Davis T , Maines TR . J Virol 2018 92 (16) ![]() While several swine-origin influenza A H3N2 variant (H3N2v) viruses isolated from humans prior to 2011 have been previously characterized for their virulence and transmissibility in ferrets, recent genetic and antigenic divergence of H3N2v viruses warrants an updated assessment of their pandemic potential. Here, four contemporary H3N2v viruses isolated during 2011-2016 were evaluated for their replicative ability in both in vitro and in vivo mammalian models, as well as their transmissibility among ferrets. We found that all four H3N2v viruses possessed similar or enhanced replication capacity in a human bronchial epithelium cell line (Calu-3) compared to a human seasonal influenza virus, suggestive of strong fitness in human respiratory tract cells. The majority of H3N2v viruses examined in our study were mildly virulent in mice and capable of replicating in mouse lungs with different degrees of efficiency. In ferrets, all four H3N2v viruses caused moderate morbidity and exhibited comparable titers in the upper respiratory tract, but only 2 of the 4 viruses replicated in the lower respiratory tract in this model. Furthermore, despite efficient transmission among cohoused ferrets, recently isolated H3N2v viruses displayed considerable variance in their ability to transmit by respiratory droplets. The lack of a full understanding of the molecular correlates of virulence and transmission underscores the need for close genotypic and phenotypic monitoring of H3N2v viruses and the importance of continued surveillance to improve pandemic preparedness.Importance: Swine-origin influenza viruses of the H3N2 subtype, with the HA and NA derived from historic human seasonal influenza viruses, continue to cross species barriers and cause human infections, posing an indelible threat to public health. To help us better understand the potential risk associated with swine-origin H3N2v viruses that emerged in the U.S between 2011-2016 influenza seasons, we use both in vitro and in vivo models to characterize the ability of these viruses to replicate, caused disease, and transmit in mammalian hosts. The efficient respiratory droplet transmission exhibited by some of the H3N2v viruses in the ferret model combined with the existing evidence of low immunity against such viruses in young children and older adults highlights their pandemic potential. Extensive surveillance and risk assessment of H3N2v viruses should continue to be an essential component of our pandemic preparedness strategy. |
Influenza-Associated Parotitis During the 2014-2015 Influenza Season in the United States.
Rolfes MA , Millman AJ , Talley P , Elbadawi LI , Kramer NA , Barnes JR , Blanton L , Davis JP , Cole S , Dreisig JJ , Garten R , Haupt T , Jackson MA , Kocharian A , Leifer D , Lynfield R , Martin K , McHugh L , Robinson S , Turabelidze G , Webber LA , Pearce Weinberg M , Wentworth DE , Finelli L , Jhung MA . Clin Infect Dis 2018 67 (4) 485-492 ![]() ![]() Background: During the 2014-2015 influenza season in the United States, 256 cases of influenza-associated parotitis were reported from 27 states. We conducted a case-control study and laboratory investigation to further describe this rare clinical manifestation of influenza. Methods: During February 2015-April 2015, we interviewed 50 cases (with parotitis) and 124 ill controls (without parotitis) with laboratory-confirmed influenza; participants resided in 11 states and were matched by age, state, hospital admission status, and specimen collection date. Influenza viruses were characterized using real-time polymerase chain reaction and next-generation sequencing. We compared cases and controls using conditional logistic regression. Specimens from additional reported cases were also analyzed. Results: Cases, 73% of whom were aged <20 years, experienced painful (86%), unilateral (68%) parotitis a median of 4 (range, 0-16) days after onset of systemic or respiratory symptoms. Cases were more likely than controls to be male (76% vs 51%; P = .005). We detected influenza A(H3N2) viruses, genetic group 3C.2a, in 100% (32/32) of case and 92% (105/108) of control specimens sequenced (P = .22). Influenza B and A(H3N2) 3C.3 and 3C.3b genetic group virus infections were detected in specimens from additional cases. Conclusions: Influenza-associated parotitis, as reported here and in prior sporadic case reports, seems to occur primarily with influenza A(H3N2) virus infection. Because of the different clinical and infection control considerations for mumps and influenza virus infections, we recommend clinicians consider influenza in the differential diagnoses among patients with acute parotitis during the influenza season. |
Maternal plasma per- and polyfluoroalkyl substance concentrations in early pregnancy and maternal and neonatal thyroid function in a prospective birth cohort: Project Viva (USA)
Preston EV , Webster TF , Oken E , Claus Henn B , McClean MD , Rifas-Shiman SL , Pearce EN , Braverman LE , Calafat AM , Ye X , Sagiv SK . Environ Health Perspect 2018 126 (2) 027013 BACKGROUND: Prenatal exposure to some per- and polyfluoroalkyl substances (PFASs) may disrupt maternal and neonatal thyroid function, which is critical for normal growth and neurodevelopment. OBJECTIVES: We examined associations of PFAS exposure during early pregnancy with maternal and neonatal thyroid hormone levels. METHODS: We studied 732 mothers and 480 neonates in Project Viva, a longitudinal prebirth cohort in Boston, Massachusetts. We quantified six PFASs, including perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), and maternal thyroid hormones [thyroxine (T4), Free T4 Index (FT4I), thyroid stimulating hormone (TSH)] in plasma samples collected at a median 9.6 wk gestation and neonatal T4 levels from postpartum heel sticks. We estimated associations of PFAS concentrations with thyroid hormone levels using covariate-adjusted linear regression models and explored effect measure modification by maternal thyroid peroxidase antibody (TPOAb) status and infant sex. RESULTS: PFAS concentrations were not associated with maternal T4, but PFOA, perfluorohexane sulfonate (PFHxS), and 2-(N-methyl-perfluorooctane sulfonamido) acetate (MeFOSAA) were inversely associated with maternal FT4I [e.g., -1.87% (95% confidence interval (CI): -3.40, -0.31) per interquartile (IQR) increase in PFOA]. PFAS concentrations [PFOA, PFOS, and perfluorononanoate (PFNA)] were inversely associated with TSH levels in TPOAb-positive women only. Prenatal PFOS, PFOA, and PFHxS concentrations were inversely associated with T4 levels in male [e.g., PFHxS, quartile 4 vs.1: -2.51mug/dL (95% CI: -3.99, -1.04 )], but not female neonates [0.40mug/dL (95% CI: -0.98, 1.79)]. CONCLUSIONS: In this study, prenatal exposure to some PFASs during early pregnancy was inversely associated with maternal FT4I and neonatal T4 in male infants. These results support the hypothesis that prenatal exposure to PFASs influences thyroid function in both mothers and infants. https://doi.org/10.1289/EHP2534. |
Viral and parasitic pathogen burden and the association with stroke in a population-based cohort
Pearce BD , Bracher A , Jones JL , Kruszon-Moran D . Int J Stroke 2017 13 (5) 1747493017729269 Background Higher cumulative burden of viral and bacterial pathogens may increase the risk of stroke, but the contribution of parasitic infections in relation to cumulative pathogen burden and risk of stroke has rarely been examined. Aim To estimate the association of multiple persistent viral and parasitic infections with stroke in a representative sample of adults in the United States. Methods Serological evidence of prior infection was categorized as positive for 0-1, 2, 3, or 4-5 infections based on immunoglobulin G seropositivity to cytomegalovirus, hepatitis A virus, hepatitis B virus, Toxoplasma gondii, and Toxocara spp. in 13,904 respondents from the National Health and Nutrition Examination Survey III. Regression analysis was used to estimate the cross-sectional association between serological evidence of prior infection and history of stroke adjusting for demographic risk factors, and potential mediators of stroke. Results Age-adjusted models that included serological evidence of prior infection to cytomegalovirus, hepatitis A virus, hepatitis B virus, Toxoplasma gondii, and Toxocara spp. showed that adults in the highest serological evidence of prior infection category (4-5 infections) had a higher prevalence of stroke (5.50%, 95% confidence interval 2.44-10.46%) than those in the lowest serological evidence of prior infection categories (1.49%, 95% confidence interval 1.01-2.11%), and a trend test suggested a graded association between serological evidence of prior infection and stroke ( p = 0.02). In multivariable logistic regression models, the positive association of serological evidence of prior infection with stroke prevalence remained significant after adjustment for other significant risk factors (odds ratio = 1.4, p = 0.01) but was only significant among those aged 20-59 (odds ratio = 2.0, p = 0.005) and not among those aged 60-69 ( p = 0.78) or 70 and older ( p = 0.43). Conclusion We found support for a connection between serological evidence of prior infection to cytomegalovirus, hepatitis A virus, hepatitis B virus, Toxoplasma gondii, and Toxocara spp. and stroke among those aged 20-59. There may be a need to consider common parasitic infections in addition to viral and bacterial pathogens when calculating serological evidence of prior infection in relation to cerebrovascular disease. |
Pathogenicity testing of influenza candidate vaccine viruses in the ferret model
Belser JA , Johnson A , Pulit-Penaloza JA , Pappas C , Pearce MB , Tzeng WP , Hossain MJ , Ridenour C , Wang L , Chen LM , Wentworth DE , Katz JM , Maines TR , Tumpey TM . Virology 2017 511 135-141 The development of influenza candidate vaccine viruses (CVVs) for pre-pandemic vaccine production represents a critical step in pandemic preparedness. The multiple subtypes and clades of avian or swine origin influenza viruses circulating world-wide at any one time necessitates the continuous generation of CVVs to provide an advanced starting point should a novel zoonotic virus cross the species barrier and cause a pandemic. Furthermore, the evolution and diversity of novel influenza viruses that cause zoonotic infections requires ongoing monitoring and surveillance, and, when a lack of antigenic match between circulating viruses and available CVVs is identified, the production of new CVVs. Pandemic guidelines developed by the WHO Global Influenza Program govern the design and preparation of reverse genetics-derived CVVs, which must undergo numerous safety and quality tests prior to human use. Confirmation of reassortant CVV attenuation of virulence in ferrets relative to wild-type virus represents one of these critical steps, yet there is a paucity of information available regarding the relative degree of attenuation achieved by WHO-recommended CVVs developed against novel viruses with pandemic potential. To better understand the degree of CVV attenuation in the ferret model, we examined the relative virulence of six A/Puerto Rico/8/1934-based CVVs encompassing five different influenza A subtypes (H2N3, H5N1, H5N2, H5N8, and H7N9) compared with the respective wild-type virus in ferrets. Despite varied virulence of wild-type viruses in the ferret, all CVVs examined showed reductions in morbidity and viral shedding in upper respiratory tract tissues. Furthermore, unlike the wild-type counterparts, none of the CVVs spread to extrapulmonary tissues during the acute phase of infection. While the magnitude of virus attenuation varied between virus subtypes, collectively we show the reliable and reproducible attenuation of CVVs that have the A/Puerto Rico/9/1934 backbone in a mammalian model. |
Neuraminidase-based recombinant virus-like particles protect against lethal avian influenza A(H5N1) virus infection in ferrets.
Smith GE , Sun X , Bai Y , Liu YV , Massare MJ , Pearce MB , Belser JA , Maines TR , Creager HM , Glenn GM , Flyer D , Pushko P , Levine MZ , Tumpey TM . Virology 2017 509 90-97 ![]() Avian influenza A (H5N1) viruses represent a growing threat for an influenza pandemic. The presence of widespread avian influenza virus infections further emphasizes the need for vaccine strategies for control of pre-pandemic H5N1 and other avian influenza subtypes. Influenza neuraminidase (NA) vaccines represent a potential strategy for improving vaccines against avian influenza H5N1 viruses. To evaluate a strategy for NA vaccination, we generated a recombinant influenza virus-like particle (VLP) vaccine comprised of the NA protein of A/Indonesia/05/2005 (H5N1) virus. Ferrets vaccinated with influenza N1 NA VLPs elicited high-titer serum NA-inhibition (NI) antibody titers and were protected from lethal challenge with A/Indonesia/05/2005 virus. Moreover, N1-immune ferrets shed less infectious virus than similarly challenged control animals. In contrast, ferrets administered control N2 NA VLPs were not protected against H5N1 virus challenge. These results provide support for continued development of NA-based vaccines against influenza H5N1 viruses. |
Maternal perchlorate exposure in pregnancy and altered birth outcomes
Rubin R , Pearl M , Kharrazi M , Blount BC , Miller MD , Pearce EN , Valentin-Blasini L , DeLorenze G , Liaw J , Hoofnagle AN , Steinmaus C . Environ Res 2017 158 72-81 BACKGROUND: At high medicinal doses perchlorate is known to decrease the production of thyroid hormone, a critical factor for fetal development. In a large and uniquely exposed cohort of pregnant women, we recently identified associations between environmental perchlorate exposures and decreased maternal thyroid hormone during pregnancy. Here, we investigate whether perchlorate might be associated with birthweight or preterm birth in the offspring of these women. METHODS: Maternal urinary perchlorate, serum thyroid hormone concentrations, birthweight, gestational age, and urinary nitrate, thiocyanate, and iodide were collected in 1957 mother-infant pairs from San Diego County during 2000-2003, a period when the county's water supply was contaminated with perchlorate. Associations between perchlorate exposure and birth outcomes were examined using linear and logistic regression analyses adjusted for maternal age, weight, race/ethnicity, and other factors. RESULTS: Perchlorate was not associated with birth outcomes in the overall population. However, in analyses confined to male infants, log10 maternal perchlorate concentrations were associated with increasing birthweight (beta=143.1gm, p=0.01), especially among preterm births (beta=829.1g, p<0.001). Perchlorate was associated with male preterm births ≥2500g (odds ratio=3.03, 95% confidence interval=1.09-8.40, p-trend=0.03). Similar associations were not seen in females. CONCLUSIONS: This is the first study to identify associations between perchlorate and increasing birthweight. Further research is needed to explore the differences we identified related to infant sex, preterm birth, and other factors. Given that perchlorate exposure is ubiquitous, and that long-term impacts can follow altered birth outcomes, future research on perchlorate could have widespread public health importance. |
Preexisting immunity not frailty phenotype predicts influenza post vaccination titers among older veterans
Van Epps P , Tumpey T , Pearce MB , Golding H , Higgins P , Hornick T , Burant C , Wilson BM , Banks R , Gravenstein S , Canaday DH . Clin Vaccine Immunol 2017 24 (3) Both preexisting immunity to influenza and age have been shown to be a correlate of influenza vaccine response. Frailty, an indicator of functional impairment in older adults, has also been shown in one study to predict lower influenza vaccine responses among non-veterans. In the current study we aimed to determine the association between frailty, preexisting immunity and immune response to influenza vaccine in older veterans. We analyzed 117 subjects (age range 62-95 years; median 81) divided into 3 cohorts based on the Fried frailty test: non-frail (NF: N=23; median age 68), pre-frail (PF: N=50; median age 80) and frail (F:N=44; median age 82) during the 2010-2011 and 11-12 influenza seasons. Subjects received the seasonal trivalent inactivated influenza vaccine and baseline and post-vaccination samples were obtained. Anti-influenza humoral immunity as measured by hemagglutinin inhibition (HI) and microneutralization (MN) assays were measured for influenza B, A(H1N1)pdm09 and A(H3N2) viruses. Post vaccination-titers to Influenza vaccine were not different between frail and NF subjects overall in this older subset of veterans. However, preexisting HI titers strongly correlated with post-vaccination titers among all functional status groups. When microneutralization titers are compared, the association between preexisting immunity and vaccine response varies by frailty status with the highest correlation observed in the NF subjects. In conclusion, preexisting immunity rather than frailty appear to predict post-influenza vaccine titer in this older veteran cohort. |
Enhanced virulence of clade 2.3.2.1 highly pathogenic avian influenza A H5N1 viruses in ferrets
Pearce MB , Pappas C , Gustin KM , Davis CT , Pantin-Jackwood MJ , Swayne DE , Maines TR , Belser JA , Tumpey TM . Virology 2016 502 114-122 ![]() Sporadic avian to human transmission of highly pathogenic avian influenza (HPAI) A(H5N1) viruses necessitates the analysis of currently circulating and evolving clades to assess their potential risk. Following the spread and sustained circulation of clade 2 viruses across multiple continents, numerous subclades and genotypes have been described. To better understand the pathogenesis associated with the continued diversification of clade 2A(H5N1) influenza viruses, we investigated the relative virulence of eleven human and poultry isolates collected from 2006 to 2013 by determining their ability to cause disease in the ferret model. Numerous clade 2 viruses, including a clade 2.2 avian isolate, a 2.2.2.1 human isolate, and two 2.2.1 human isolates, were found to be of low virulence in the ferret model, though lethality was detected following infection with one 2.2.1 human isolate. In contrast, three of six clade 2.3.2.1 avian isolates tested led to severe disease and death among infected ferrets. Clade 2.3.2.1b and 2.3.2.1c isolates, but not 2.3.2.1a isolates, were associated with ferret lethality. All A(H5N1) viruses replicated efficiently in the respiratory tract of ferrets regardless of their virulence and lethality. However, lethal isolates were characterized by systemic viral dissemination, including detection in the brain and enhanced histopathology in lung tissues. The finding of disparate virulence phenotypes between clade 2A(H5N1) viruses, notably differences between subclades of 2.3.2.1 viruses, suggests there are distinct molecular determinants present within the established subclades, the identification of which will assist in molecular-based surveillance and public health efforts against A(H5N1) viruses. |
Thyroid Hormones and Moderate Exposure to Perchlorate during Pregnancy in Women in Southern California
Steinmaus C , Pearl M , Kharrazi M , Blount BC , Miller MD , Pearce EN , Valentin-Blasini L , DeLorenze G , Hoofnagle AN , Liaw J . Environ Health Perspect 2016 124 (6) 861-7 BACKGROUND: Findings from national surveys suggest that everyone in the United States is exposed to perchlorate. At high doses, perchlorate, thiocyanate, and nitrate inhibit iodide uptake into the thyroid and decrease thyroid hormone production. Small changes in thyroid hormones during pregnancy, including changes within normal reference ranges, have been linked to cognitive function declines in the offspring. OBJECTIVES: We evaluated the potential effects of low environmental exposures to perchlorate on thyroid function. METHODS: Serum thyroid hormones and anti-thyroid antibodies and urinary perchlorate, thiocyanate, nitrate, and iodide concentrations were measured in 1,880 pregnant women from San Diego County, California, during 2000-2003, a period when much of the area's water supply was contaminated from an industrial plant with perchlorate at levels near the 2007 California regulatory standard of 6 μg/L. Linear regression was used to evaluate associations between urinary perchlorate and serum thyroid hormone concentrations in models adjusted for urinary creatinine and thiocyanate, maternal age and education, ethnicity, and gestational age at serum collection. RESULTS: The median urinary perchlorate concentration was 6.5 μg/L, about two times higher than in the general U.S. POPULATION: Adjusted associations were identified between increasing log10 perchlorate and decreasing total thyroxine (T4) [regression coefficient (β) = -0.70; 95% CI: -1.06, -0.34], decreasing free thyroxine (fT4) (β = -0.053; 95% CI: -0.092, -0.013), and increasing log10 thyroid-stimulating hormone (β = 0.071; 95% CI: 0.008, 0.133). CONCLUSIONS: These results suggest that environmental perchlorate exposures may affect thyroid hormone production during pregnancy. This could have implications for public health given widespread perchlorate exposure and the importance of thyroid hormone in fetal neurodevelopment. CITATION: Steinmaus C, Pearl M, Kharrazi M, Blount BC, Miller MD, Pearce EN, Valentin-Blasini L, DeLorenze G, Hoofnagle AN, Liaw J. 2016. Thyroid hormones and moderate exposure to perchlorate during pregnancy in women in Southern California. Environ Health Perspect 124:861-867; http://dx.doi.org/10.1289/ehp.1409614. |
Comparative studies of infectivity, immunogenicity and cross-protective efficacy of live attenuated influenza vaccines containing nucleoprotein from cold-adapted or wild-type influenza virus in a mouse model.
Isakova-Sivak I , Korenkov D , Smolonogina T , Tretiak T , Donina S , Rekstin A , Naykhin A , Shcherbik S , Pearce N , Chen LM , Bousse T , Rudenko L . Virology 2016 500 209-217 ![]() This study sought to improve an existing live attenuated influenza vaccine (LAIV) by including nucleoprotein (NP) from wild-type virus rather than master donor virus (MDV). H7N9 LAIV reassortants with 6:2 (NP from MDV) and 5:3 (NP from wild-type virus) genome compositions were compared with regard to their growth characteristics, induction of humoral and cellular immune responses in mice, and ability to protect mice against homologous and heterologous challenge viruses. Although, in general, the 6:2 reassortant induced greater cell-mediated immunity in C57BL6 mice than the 5:3 vaccine, mice immunized with the 5:3 LAIV were better protected against heterologous challenge. The 5:3 LAIV-induced CTLs also had better in vivo killing activity against target cells loaded with the NP366 epitope of recent influenza viruses. Modification of the genome of reassortant vaccine viruses by incorporating the NP gene from wild-type viruses represents a simple strategy to improve the immunogenicity and cross-protection of influenza vaccines. |
Urinary iodine, thyroid function, and thyroglobulin as biomarkers of iodine status
Pearce EN , Caldwell KL . Am J Clin Nutr 2016 104 Suppl 3 898S-901S The accurate assessment of population iodine status is necessary to inform public health policies and clinical research on iodine nutrition, particularly the role of iodine adequacy in normal neurodevelopment. Urinary iodine concentration (UIC) directly reflects dietary iodine intake and is the most common indicator used worldwide to assess population iodine status. The CDC established the Ensuring the Quality of Iodine Procedures program in 2001 to provide laboratories that measure urinary iodine with an independent assessment of their analytic performance; this program fosters improvement in the assessment of UIC. Clinical laboratory tests of thyroid function (including serum concentrations of the pituitary hormone thyrotropin and the thyroid hormones thyroxine and triiodothyronine) are sometimes used as indicators of iodine status, although such use is often problematic. Even in severely iodine-deficient regions, there is a great deal of intraindividual variation in the ability of the thyroid to adapt. In most settings and in most population subgroups other than newborns, thyroid function tests are not considered sensitive indicators of population iodine status. However, the thyroid-derived protein thyroglobulin is increasingly being used for this purpose. Thyroglobulin can be measured in either serum or dried blood spot (DBS) samples. The use of DBS samples is advantageous in resource-poor regions. Improved methodologies for ascertaining maternal iodine status are needed to facilitate research on developmental correlates of iodine status. Thyroglobulin may prove to be a useful biomarker for both maternal and neonatal iodine status, but validated assay-specific reference ranges are needed for the determination of iodine sufficiency in both pregnant women and neonates, and trimester-specific ranges are possibly needed for pregnant women. UIC is currently a well-validated population biomarker, but individual biomarkers that could be used for research, patient care, and public health are lacking. |
Polybrominated diphenyl ether exposure and reproductive hormones in North American men
Makey CM , McClean MD , Braverman LE , Pearce EN , Sjodin A , Weinberg J , Webster TF . Reprod Toxicol 2016 62 46-52 BACKGROUND: Polybrominated diphenyl ethers (PBDEs) are flame retardant chemicals that are persistent organic pollutants. Animal experiments and some human studies indicate that PBDEs may adversely affect male reproductive function. OBJECTIVES: To assess the association between PBDE exposure and reproductive hormones (RHs) in a North American male adult cohort. METHODS: From 2010-11, we collected three serum samples from 27 healthy adult men. We assessed associations between PBDEs and RHs using mixed effect regression models. RESULTS: PBDEs were inversely associated with inhibin-B. In older men, increased concentrations of BDE-47 and BDE-100 were significantly associated with a decrease in inhibin-B, and an increase in follicular stimulating hormone (FSH). CONCLUSIONS: These findings suggest PBDE exposure may affect RHs in older men. We did not measure other parameters of male reproductive function and therefore these results are preliminary. |
Polybrominated diphenyl ether exposure and thyroid function tests in North American adults
Makey CM , McClean MD , Braverman LE , Pearce EN , He XM , Sjodin A , Weinberg JM , Webster TF . Environ Health Perspect 2016 124 (4) 420-5 BACKGROUND: Polybrominated diphenyl ethers (PBDEs) are flame-retardant chemicals that are added to many consumer products. Multiple animal studies have shown PBDEs to be thyroid hormone (TH) disruptors. Epidemiologic evidence of PBDE exposure associated with TH disruption has been inconclusive. OBJECTIVES: We used repeated measures to estimate associations between serum PBDE concentrations and THs in a North American adult cohort. METHODS: From 2010 to 2011, we collected ≤ 3 serum samples at approximately 6-month intervals from 52 healthy adult office workers from Boston, Massachusetts, for analysis of PBDE congeners and THs. RESULTS: The geometric mean sum concentrations of the most prevalent PBDE congeners (BDE-28, BDE-47, BDE-99, BDE-100, and BDE-153) were 22 ng/g lipid in winter 2010, 23 ng/g lipid in summer 2010, and 19 ng/g lipid in winter 2011. BDE-47 was the predominant congener. Based on a multivariable mixed regression model, we estimated that on average, a 1-ng/g serum increase in BDE-47 was associated with a 2.6-mug/dL decrease in total thyroxine (T4) (95% CI: -4.7, -0.35). Total T4 was inversely associated with each PBDE congener. Serum concentrations of PBDEs were not strongly associated with total triiodothyronine (T3), free T4, or thyroid-stimulating hormone (TSH). CONCLUSION: These results are consistent with those from animal studies showing that exposure to PBDEs is associated with a decrease in serum T4. Because the other TH concentrations did not appear to be associated with BDE exposures, our findings do not indicate effects on the pituitary-thyroid axis. Taken together, our findings suggest that PBDE exposure might decrease the binding of T4 to serum T4 binding proteins. |
Evaluation of the Physical Activity and Public Health Course for Practitioners
Evenson KR , Brown DR , Pearce E , Camplain R , Jernigan J , Epping J , Shepard DM , Dorn JM . Res Q Exerc Sport 2016 87 (2) 1-7 PURPOSE: From 1996 to 2013, a 6-day Physical Activity and Public Health Course for Practitioners has been offered yearly in the United States. An evaluation was conducted to assess the impact of the course on building public health capacity for physical activity and on shaping the physical activity and public health careers of fellows since taking the courses. METHOD: An evaluation quantified time that fellows spent in different course offerings and surveyed fellows. RESULTS: From 1996 to 2012, 410 fellows attended the course, and in 2013, 186 participated in the Web-based survey (56% response rate). The number of fellows attending the course ranged from 15 to 33 yearly. From 1996 to 2012, the course averaged 38 hr of instructional time that included topics on interventions and environment/policy work to increase physical activity, program evaluation, public health research, and health disparities. The course included consultations, collaborative work, and field-based experiences. Fellows who participated in the survey agreed that the course had a positive impact on the physical activity research or practice work they did (98%), met their expectations (96%), helped them with research/practice collaborations with other physical activity professionals (96%), assisted them in conducting higher-quality interventions/programs (95%), helped increase their professional networking in the field (93%), and had a positive impact on other work they did (91%). Following the course, 66% and 56% had further contact with faculty and other fellows, respectively. CONCLUSION: The Physical Activity and Public Health Course for Practitioners made important contributions toward building the capacity of physical activity and public health practitioners. |
Implementation of new approaches for generating conventional reassortants for live attenuated influenza vaccine based on Russian master donor viruses.
Shcherbik S , Pearce N , Kiseleva I , Larionova N , Rudenko L , Xu X , Wentworth DE , Bousse T . J Virol Methods 2015 227 33-9 ![]() Cold-adapted influenza strains A/Leningrad/134/17/57 (H2N2) and B/USSR/60/69, originally developed in Russia, have been reliable master donors of attenuation for preparing live attenuated influenza vaccines (LAIV). The classical strategy for generating LAIV reassortants is robust, but has some disadvantages. The generation of reassortants requires at least 3 passages under selective conditions after co-infection; each of these selective passages takes six days. Screening the reassortants for a genomic composition traditionally starts after a second limiting dilution cloning procedure, and the number of suitable reassortants is limited. We developed a new approach to shorten process of preparing LAIV seed viruses. Introducing the genotyping of reassortants by pyrosequencing and monitoring sequence integrity of surface antigens starting at the first selective passage allowed specific selection of suitable reassortants for the next cloning procedure and also eliminate one of the group selective passage in vaccine candidate generation. Homogeneity analysis confirmed that reducing the number of selective passages didn't affect the quality of LAIV seed viruses. Finally, the two-way hemagglutination inhibition test, implemented for all the final seed viruses, confirmed that any amino acid substitutions acquired by reassortants during egg propagation didn't affect antigenicity of the vaccine. Our new strategy reduces the time required to generate a vaccine and was used to generate seasonal LAIVs candidates for the 2012/2013, 2014/2015, and 2015/2016 seasons more rapidly. |
Generation and Characterization of Live Attenuated Influenza A(H7N9) Candidate Vaccine Virus Based on Russian Donor of Attenuation.
Shcherbik S , Pearce N , Balish A , Jones J , Thor S , Davis CT , Pearce M , Tumpey T , Cureton D , Chen LM , Villanueva J , Bousse TL . PLoS One 2015 10 (9) e0138951 ![]() BACKGROUND: Avian influenza A (H7N9) virus has emerged recently and continues to cause severe disease with a high mortality rate in humans prompting the development of candidate vaccine viruses. Live attenuated influenza vaccines (LAIV) are 6:2 reassortant viruses containing the HA and NA gene segments from wild type influenza viruses to induce protective immune responses and the six internal genes from Master Donor Viruses (MDV) to provide temperature sensitive, cold-adapted and attenuated phenotypes. METHODOLOGY/PRINCIPAL FINDINGS: LAIV candidate A/Anhui/1/2013(H7N9)-CDC-LV7A (abbreviated as CDC-LV7A), based on the Russian MDV, A/Leningrad/134/17/57 (H2N2), was generated by classical reassortment in eggs and retained MDV temperature-sensitive and cold-adapted phenotypes. CDC-LV7A had two amino acid substitutions N123D and N149D (H7 numbering) in HA and one substitution T10I in NA. To evaluate the role of these mutations on the replication capacity of the reassortants in eggs, the recombinant viruses A(H7N9)RG-LV1 and A(H7N9)RG-LV2 were generated by reverse genetics. These changes did not alter virus antigenicity as ferret antiserum to CDC-LV7A vaccine candidate inhibited hemagglutination by homologous A(H7N9) virus efficiently. Safety studies in ferrets confirmed that CDC-LV7A was attenuated compared to wild-type A/Anhui/1/2013. In addition, the genetic stability of this vaccine candidate was examined in eggs and ferrets by monitoring sequence changes acquired during virus replication in the two host models. No changes in the viral genome were detected after five passages in eggs. However, after ten passages additional mutations were detected in the HA gene. The vaccine candidate was shown to be stable in the ferret model; post-vaccination sequence data analysis showed no changes in viruses collected in nasal washes present at day 5 or day 7. CONCLUSIONS/SIGNIFICANCE: Our data indicate that the A/Anhui/1/2013(H7N9)-CDC-LV7A reassortant virus is a safe and genetically stable candidate vaccine virus that is now available for distribution by WHO to vaccine manufacturers. |
Recombinant H7 hemagglutinin forms subviral particles that protect mice and ferrets from challenge with H7N9 influenza virus
Pushko P , Pujanauski LM , Sun X , Pearce M , Hidajat R , Kort T , Schwartzman LM , Tretyakova I , Chunqing L , Taubenberger JK , Tumpey TM . Vaccine 2015 33 (38) 4975-82 A novel avian-origin influenza A H7N9 virus emerged in China in 2013 and continues to cause sporadic human infections with mortality rates approaching 35%. Currently there are no approved human vaccines for H7N9 virus. Recombinant approaches including hemagglutinin (HA) and virus-like particles (VLPs) have resulted in experimental vaccines with advantageous safety and manufacturing characteristics. While high immunogenicity of VLP vaccines has been attributed to the native conformation of HA arranged in the regular repeated patterns within virus-like structures, there is limited data regarding molecular organization of HA within recombinant HA vaccine preparations. In this study, the full-length recombinant H7 protein (rH7) of A/Anhui/1/2013 (H7N9) virus was expressed in Sf9 cells. We showed that purified full-length rH7 retained functional ability to agglutinate red blood cells and formed oligomeric pleomorphic subviral particles (SVPs) of approximately 20nm in diameter composed of approximately 10 HA0 molecules. No significant quantities of free monomeric HA0 were observed in rH7 preparation by size exclusion chromatography. Immunogenicity and protective efficacy of rH7 SVPs was confirmed in the mouse and ferret challenge models suggesting that SVPs can be used for vaccination against H7N9 virus. |
The Global Trachoma Mapping Project: methodology of a 34-country population-based study
Solomon AW , Pavluck AL , Courtright P , Aboe A , Adamu L , Alemayehu W , Alemu M , Alexander ND , Kello AB , Bero B , Brooker SJ , Chu BK , Dejene M , Emerson PM , Flueckiger RM , Gadisa S , Gass K , Gebre T , Habtamu Z , Harvey E , Haslam D , King JD , Mesurier RL , Lewallen S , Lietman TM , MacArthur C , Mariotti SP , Massey A , Mathieu E , Mekasha A , Millar T , Mpyet C , Muñoz BE , Ngondi J , Ogden S , Pearce J , Sarah V , Sisay A , Smith JL , Taylor HR , Thomson J , West SK , Willis R , Bush S , Haddad D , Foster A . Ophthalmic Epidemiol 2015 22 (3) 214-25 PURPOSE: To complete the baseline trachoma map worldwide by conducting population-based surveys in an estimated 1238 suspected endemic districts of 34 countries. METHODS: A series of national and sub-national projects owned, managed and staffed by ministries of health, conduct house-to-house cluster random sample surveys in evaluation units, which generally correspond to "health district" size: populations of 100,000-250,000 people. In each evaluation unit, we invite all residents aged 1 year and older from h households in each of c clusters to be examined for clinical signs of trachoma, where h is the number of households that can be seen by 1 team in 1 day, and the product h x c is calculated to facilitate recruitment of 1019 children aged 1-9 years. In addition to individual-level demographic and clinical data, household-level water, sanitation and hygiene data are entered into the purpose-built LINKS application on Android smartphones, transmitted to the Cloud, and cleaned, analyzed and ministry-of-health-approved via a secure web-based portal. The main outcome measures are the evaluation unit-level prevalence of follicular trachoma in children aged 1-9 years, prevalence of trachomatous trichiasis in adults aged 15 + years, percentage of households using safe methods for disposal of human feces, and percentage of households with proximate access to water for personal hygiene purposes. RESULTS: In the first year of fieldwork, 347 field teams commenced work in 21 projects in 7 countries. CONCLUSION: With an approach that is innovative in design and scale, we aim to complete baseline mapping of trachoma throughout the world in 2015. |
Phase 1 study of pandemic h1 DNA vaccine in healthy adults
Crank MC , Gordon IJ , Yamshchikov GV , Sitar S , Hu Z , Enama ME , Holman LA , Bailer RT , Pearce MB , Koup RA , Mascola JR , Nabel GJ , Tumpey TM , Schwartz RM , Graham BS , Ledgerwood JE . PLoS One 2015 10 (4) e0123969 BACKGROUND: A novel, swine-origin influenza A (H1N1) virus was detected worldwide in April 2009, and the World Health Organization (WHO) declared a global pandemic that June. DNA vaccine priming improves responses to inactivated influenza vaccines. We describe the rapid production and clinical evaluation of a DNA vaccine encoding the hemagglutinin protein of the 2009 pandemic A/California/04/2009(H1N1) influenza virus, accomplished nearly two months faster than production of A/California/07/2009(H1N1) licensed monovalent inactivated vaccine (MIV). METHODS: 20 subjects received three H1 DNA vaccinations (4 mg intramuscularly with Biojector) at 4-week intervals. Eighteen subjects received an optional boost when the licensed H1N1 MIV became available. The interval between the third H1 DNA injection and MIV boost was 3-17 weeks. Vaccine safety was assessed by clinical observation, laboratory parameters, and 7-day solicited reactogenicity. Antibody responses were assessed by ELISA, HAI and neutralization assays, and T cell responses by ELISpot and flow cytometry. RESULTS: Vaccinations were safe and well-tolerated. As evaluated by HAI, 6/20 developed positive responses at 4 weeks after third DNA injection and 13/18 at 4 weeks after MIV boost. Similar results were detected in neutralization assays. T cell responses were detected after DNA and MIV. The antibody responses were significantly amplified by the MIV boost, however, the boost did not increased T cell responses induced by DNA vaccine. CONCLUSIONS: H1 DNA vaccine was produced quickly, was well-tolerated, and had modest immunogenicity as a single agent. Other HA DNA prime-MIV boost regimens utilizing one DNA prime vaccination and longer boost intervals have shown significant immunogenicity. Rapid and large-scale production of HA DNA vaccines has the potential to contribute to an efficient response against future influenza pandemics. TRIAL REGISTRATION: Clinicaltrials.gov NCT00973895. |
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