Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 180
Filtrar
1.
medRxiv ; 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39228738

RESUMO

The generation time, representing the interval between infections in primary and secondary cases, is essential for understanding and predicting the transmission dynamics of seasonal influenza, including the real-time effective reproduction number (Rt). However, comprehensive generation time estimates for seasonal influenza, especially post the 2009 influenza pandemic, are lacking. We estimated the generation time utilizing data from a 7-site case-ascertained household study in the United States over two influenza seasons, 2021/2022 and 2022/2023. More than 200 individuals who tested positive for influenza and their household contacts were enrolled within 7 days of the first illness in the household. All participants were prospectively followed for 10 days completing daily symptom diaries and collecting nasal swabs, which were tested for influenza via RT-PCR. We analyzed these data by modifying a previously published Bayesian data augmentation approach that imputes infection times of cases to obtain both intrinsic (assuming no susceptible depletion) and realized (observed within household) generation times. We assessed the robustness of the generation time estimate by varying the incubation period, and generated estimates of the proportion of transmission before symptomatic onset, infectious period, and latent period. We estimated a mean intrinsic generation time of 3.2 (95% credible interval, CrI: 2.9-3.6) days, with a realized household generation time of 2.8 (95% CrI: 2.7-3.0) days. The generation time exhibited limited sensitivity to incubation period variation. Estimates of the proportion of transmission that occurred before symptom onset, the infectious period, and the latent period were sensitive to variation in incubation periods. Our study contributes to the ongoing efforts to refine estimates of the generation time for influenza. Our estimates, derived from recent data following the COVID-19 pandemic, are consistent with previous pre-pandemic estimates, and will be incorporated into real-time Rt estimation efforts.

2.
Am J Epidemiol ; 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39218430

RESUMO

Households are a primary setting for transmission of SARS-CoV-2. We examined the role of prior SARS-CoV-2 immunity on the risk of infection in household close contacts. Households in the United States with an individual who tested positive for SARS-CoV-2 during September 2021-May 2023 were enrolled if the index case's illness began ≤6 days prior. Household members had daily self-collected nasal swabs tested by RT-PCR for SARS-CoV-2. The effects of prior SARS-CoV-2 immunity (vaccination, prior infection, or hybrid immunity) on SARS-CoV-2 infection risk among household contacts were assessed by robust, clustered multivariable Poisson regression. Of 1,532 contacts (905 households), 8% had immunity from prior infection alone, 51% from vaccination alone, 29% hybrid immunity, and 11% had no prior immunity. Sixty percent of contacts tested SARS-CoV-2-positive during follow-up. The adjusted risk of SARS-CoV-2 infection was lowest among contacts with vaccination and prior infection (aRR: 0.81, 95% CI: 0.70, 0.93, compared with contacts with no prior immunity) and was lowest when the last immunizing event occurred ≤6 months before COVID-19 affected the household (aRR: 0.69, 95% CI: 0.57, 0.83). In high-transmission settings like households, immunity from COVID-19 vaccination and prior infection was synergistic in protecting household contacts from SARS-CoV-2 infection.

3.
JAMA Netw Open ; 7(8): e2430367, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39196563

RESUMO

This cross-sectional study examines whether students and employees with or without disabilities at a major academic medical center in the US feel respected and are treated equitably at their institution.


Assuntos
Pessoas com Deficiência , Humanos , Masculino , Pessoas com Deficiência/psicologia , Feminino , Centros Médicos Acadêmicos , Adulto , Cultura Organizacional , Pessoa de Meia-Idade
4.
Health Care Manage Rev ; 49(4): 272-280, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39016264

RESUMO

BACKGROUND: Leadership can be an isolating experience and leaders from underrepresented groups (URGs) may experience even greater isolation and vulnerability because of lack of representation. Given the collaborative nature of medicine, leadership programs for physicians need to address isolation. Social support is one mechanism to combat this isolation; however, most leadership programs focus exclusively on skills building. PURPOSE: The Stanford Network for Advancement and Promotion (SNAP) program was developed to reduce isolation among physician leaders from URGs in academic medicine leadership by building a supportive network of peers. METHODOLOGY/APPROACH: Ten women physicians from diverse racial/ethnic backgrounds were invited to participate in SNAP. Annual surveys were administered to participants to assess the effectiveness of SNAP on decreasing feelings of isolation and increasing professional leadership growth. The authors charted the expansion and adaptation of the program model across gender and in additional settings. RESULTS: SNAP effectively created a sense of community among the physician leaders. Participants also reported feeling challenged by the program and that they had grown in terms of critical thinking, organizational knowledge, and empowerment as leaders. Participants found community building to be the most valuable program component. Because of this success, the SNAP model has been adapted to create 10 additional cohorts. CONCLUSION: Leadership programs like SNAP that focus on reducing isolation are instrumental for retaining and promoting the career advancement of physicians from URGs. PRACTICE IMPLICATIONS: Developing a diverse workforce of academic physicians is essential to providing high-quality and equitable clinical care, research, and medical education.


Assuntos
Liderança , Grupos Minoritários , Humanos , Feminino , Mobilidade Ocupacional , Apoio Social , Centros Médicos Acadêmicos/organização & administração , Médicas , Adulto , Inquéritos e Questionários , Pessoa de Meia-Idade , Desenvolvimento de Programas , Desenvolvimento de Pessoal , Avaliação de Programas e Projetos de Saúde
5.
bioRxiv ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38948732

RESUMO

Sex differences have been observed in acute COVID-19 and Long COVID (LC) outcomes, with greater disease severity and mortality during acute infection in males and a greater proportion of females developing LC. We hypothesized that sex-specific immune dysregulation contributes to the pathogenesis of LC. To investigate the immunologic underpinnings of LC development and persistence, we used single-cell transcriptomics, single-cell proteomics, and plasma proteomics on blood samples obtained during acute SARS-CoV-2 infection and at 3 and 12 months post-infection in a cohort of 45 patients who either developed LC or recovered. Several sex-specific immune pathways were associated with LC. Specifically, males who would develop LC at 3 months had widespread increases in TGF-ß signaling during acute infection in proliferating NK cells. Females who would develop LC demonstrated increased expression of XIST, an RNA gene implicated in autoimmunity, and increased IL1 signaling in monocytes at 12 months post infection. Several immune features of LC were also conserved across sexes. Both males and females with LC had reduced co-stimulatory signaling from monocytes and broad upregulation of NF-κB transcription factors. In both sexes, those with persistent LC demonstrated increased LAG3, a marker of T cell exhaustion, reduced ETS1 transcription factor expression across lymphocyte subsets, and elevated intracellular IL-4 levels in T cell subsets, suggesting that ETS1 alterations may drive an aberrantly elevated Th2-like response in LC. Altogether, this study describes multiple innate and adaptive immune correlates of LC, some of which differ by sex, and offers insights toward the pursuit of tailored therapeutics.

6.
PLoS One ; 19(7): e0305300, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39052659

RESUMO

IMPORTANCE: The COVID-19 pandemic has led to 775 million documented cases and over 7 million deaths worldwide as of March 2024 and is an ongoing health crisis. To limit viral spread within households and in the community, public health officials have recommended self-isolation, self-quarantine of exposed household contacts, and mask use. Yet, risk of household transmission (HHT) may be underestimated due to low frequency of sampling, and risk factors for HHT are not well understood. OBJECTIVES: To estimate the secondary attack rate of SARS-CoV-2 within households and to define the risk factors for new infections in household members who are in close contact with the index case. DESIGN, SETTING, AND PARTICIPANTS: In this prospective cohort study, from March 2020-December 2021 we enrolled 60 households with index cases who tested positive for SARS-CoV-2. All household contacts and index cases were tested daily for SARS-CoV-2 via reverse transcription polymerase chain reaction (RT-PCR) using self-collected anterior nares specimens. Households were followed until all study participants in the household tested negative for SARS-CoV-2 for seven consecutive days. We collected sex, age, race/ethnicity, comorbidities, and relationship to index case for secondary contacts, household level characteristics including primary income, household density, and square feet per person on property. We compared the sociodemographic variables between COVID-19 positive and negative household members and between households where secondary transmission did and did not occur. MAIN OUTCOMES AND MEASURES: Daily anterior nares swabs were tested for SARS-CoV-2 using RT-PCR, in order to assess duration of nasal shedding of SARS-CoV-2, as well as risk of transmission to secondary household contacts. RESULTS: Of the 163 participants in this study, 84 (51.5%) were women; median age (IQR) was 36.0 (17.0-54.0) years of age; 78 (47.8%) were white and 48 (29.5%) were Hispanic/LatinX. Of the fifty households with household contacts, at least one secondary case occurred in twenty-six households (52.0%) and forty-five household contacts (43.7%) were infected. Secondary attack rate was lowest among children of index cases (6/23, 26.1%). Modified Poisson regression identified that the risk of transmission to household contacts increases significantly with age (Risk ratio for each increase in years of age = 1.01, 95% CI = 1.00-1.02). Mixed effects regression models identified that participants with chronic diseases, such as asthma, diabetes, cancer, or cardiac disease, had higher Cts at baseline when compared to participants without chronic diseases (6.62, 95% CI: 1.46-11.77, p = 0.02) and show a slower rate of increase in Ct over time (-0.43, 95% CI: -0.77 to -0.09, p = 0.02). CONCLUSIONS AND RELEVANCE: This study suggests that HHT represents a key source of community-based infection of SARS-CoV-2. Allocation of resources for contact investigations and prevention interventions should focus on the individuals at highest risk of infection in households, especially those with higher density homes.


Assuntos
COVID-19 , Características da Família , SARS-CoV-2 , Eliminação de Partículas Virais , Humanos , COVID-19/transmissão , COVID-19/epidemiologia , COVID-19/virologia , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , SARS-CoV-2/isolamento & purificação , Estudos Prospectivos , Adolescente , Criança , Adulto Jovem , Fatores de Risco , Pré-Escolar , Idoso
7.
J Pediatric Infect Dis Soc ; 13(8): 421-429, 2024 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-38860591

RESUMO

BACKGROUND: With the future epidemiology and evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) uncertain, the use of safe and effective coronavirus disease 2019 (COVID-19) vaccines in pediatric populations remains important. METHODS: We report data from two open-label substudies of an ongoing phase 1/2/3 master study (NCT05543616) investigating the safety and immunogenicity of a variant-adapted bivalent COVID-19 vaccine encoding ancestral and Omicron BA.4/BA.5 spike proteins (bivalent BNT162b2). The open-label groups presented here evaluate dose 4 with bivalent BNT162b2 in 6-month- to <12-year-olds who previously received three original (monovalent) BNT162b2 doses. In 6-month- to <5-year-olds, primary immunogenicity objectives were to demonstrate superiority (neutralizing titer) and noninferiority (seroresponse rate) to Omicron BA.4/BA.5 and noninferiority (neutralizing titer and seroresponse rate) to SARS-CoV-2 ancestral strains in participants who received bivalent BNT162b2 dose 4 compared with a matched group who received three doses of original BNT162b2 in the pivotal pediatric study (NCT04816643). In 5- to <12-year-olds, primary immunogenicity comparisons were descriptive. Reactogenicity and safety following vaccination were evaluated. RESULTS: In 6-month- to <5-year-olds, dose 4 with bivalent BNT162b2 met predefined immunogenicity superiority and noninferiority criteria against Omicron BA.4/BA.5 and ancestral strains when compared with dose 3 of original BNT162b2. In 5- to <12-year-olds, bivalent BNT162b2 induced robust Omicron BA.4/BA.5 and ancestral strain neutralizing titers comparable with dose 3 of original BNT162b2. The safety profile for dose 4 of bivalent BNT162b2 given as dose 4 was consistent with that of original BNT162b2 in 6-month- to <12-year-olds. Reactogenicity events were generally mild to moderate. No adverse events led to discontinuation. CONCLUSIONS: These safety and immunogenicity data support a favorable benefit-risk profile for a variant-adapted BNT162b2 in children <12 years old.


Assuntos
Vacina BNT162 , Vacinas contra COVID-19 , COVID-19 , Imunogenicidade da Vacina , SARS-CoV-2 , Humanos , Vacina BNT162/imunologia , Pré-Escolar , COVID-19/prevenção & controle , COVID-19/imunologia , Masculino , Feminino , SARS-CoV-2/imunologia , Lactente , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/efeitos adversos , Vacinas contra COVID-19/administração & dosagem , Anticorpos Antivirais/sangue , Criança , Anticorpos Neutralizantes/sangue , Eficácia de Vacinas , Glicoproteína da Espícula de Coronavírus/imunologia
8.
Lancet Glob Health ; 12(6): e929-e937, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38762295

RESUMO

BACKGROUND: Differentiated service delivery (DSD) for children and adolescents living with HIV can improve targeted resource use. We derived a mortality prediction score to guide clinical decision making for children and adolescents living with HIV. METHODS: Data for this retrospective observational cohort study were evaluated for all children and adolescents living with HIV and initiating antiretroviral therapy (ART); aged 0-19 years; and enrolled at Baylor clinics in Eswatini, Malawi, Lesotho, Tanzania, and Uganda between 2005 and 2020. Data for clinical prediction, including anthropometric values, physical examination, ART, WHO stage, and laboratory tests were captured at ART initiation. Backward stepwise variable selection and logistic regression were performed to develop predictive models for mortality within 1 year of ART initiation. Probabilities of mortality were generated, compared with true outcomes, internally validated, and evaluated against WHO advanced HIV criteria. FINDINGS: The study population included 16 958 children and adolescents living with HIV and initiated on ART between May 18, 2005, and Dec 18, 2020. Predictive variables for the most accurate model included: age, CD4 percentage, white blood cell count, haemoglobin concentration, platelet count, and BMI Z score as continuous variables, and WHO clinical stage and oedema, abnormal muscle tone and respiratory distress on examination as categorical variables. The area under the curve (AUC) of the predictive model was 0·851 (95% CI 0·839-0·863) in the training set and 0·822 (0·800-0·845) in the test set, compared with 0·606 (0·595-0·617) for the WHO advanced HIV criteria (p<0·0001). INTERPRETATION: This study evaluated a large, multinational population to derive a mortality prediction tool for children and adolescents living with HIV. The model more accurately predicted clinical outcomes than the WHO advanced HIV criteria and has the potential to improve DSD for children and adolescents living with HIV in high-burden settings. FUNDING: National Institute of Health Fogarty International Center.


Assuntos
Infecções por HIV , Humanos , Adolescente , Infecções por HIV/tratamento farmacológico , Infecções por HIV/mortalidade , Criança , Estudos Retrospectivos , Feminino , Masculino , Pré-Escolar , África Subsaariana/epidemiologia , Lactente , Adulto Jovem , Recém-Nascido , Fármacos Anti-HIV/uso terapêutico
10.
Artigo em Inglês | MEDLINE | ID: mdl-38709334

RESUMO

OBJECTIVES: To examine the experiences of pregnant Hispanic/Latine people with COVID-19, as well as their perspectives on COVID-19 vaccination in pregnancy. METHODS: We interviewed birthing parents who received care from a teaching hospital in California and tested positive for COVID-19 during pregnancy or delivery. We analyzed transcripts using the constant comparative method for analyzing data to using a phenomological epidemiological approach. We used root cause analysis to identify consistent themes across interviews and assess relationships between social determinants of health and COVID-19 infectivity. RESULTS: We interviewed 14 women from November 2021 to June 2022. Participants reported COVID-19 adversely impacted their clinical care and well-being during pregnancy or postpartum. Impacts among Spanish-speaking participants included unexpected financial hardships, challenges navigating in-patient experiences, and difficulty securing reliable childcare. While most participants were at least partially vaccinated, participants also described doubts and concerns about the vaccine. CONCLUSIONS: Our findings suggest that Spanish-speaking Hispanic/Latine patients could benefit from receiving more information about COVID-19 in pregnancy from their healthcare providers. Leveraging familial and social networks, providing reliable information in people's preferred language, and increasing communication through trusted partners may also help combat vaccine hesitancy.

11.
Epidemiology ; 35(3): 295-307, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38465940

RESUMO

Understanding the incidence of disease is often crucial for public policy decision-making, as observed during the COVID-19 pandemic. Estimating incidence is challenging, however, when the definition of incidence relies on tests that imperfectly measure disease, as in the case when assays with variable performance are used to detect the SARS-CoV-2 virus. To our knowledge, there are no pragmatic methods to address the bias introduced by the performance of labs in testing for the virus. In the setting of a longitudinal study, we developed a maximum likelihood estimation-based approach to estimate laboratory performance-adjusted incidence using the expectation-maximization algorithm. We constructed confidence intervals (CIs) using both bootstrapped-based and large-sample interval estimator approaches. We evaluated our methods through extensive simulation and applied them to a real-world study (TrackCOVID), where the primary goal was to determine the incidence of and risk factors for SARS-CoV-2 infection in the San Francisco Bay Area from July 2020 to March 2021. Our simulations demonstrated that our method converged rapidly with accurate estimates under a variety of scenarios. Bootstrapped-based CIs were comparable to the large-sample estimator CIs with a reasonable number of incident cases, shown via a simulation scenario based on the real TrackCOVID study. In more extreme simulated scenarios, the coverage of large-sample interval estimation outperformed the bootstrapped-based approach. Results from the application to the TrackCOVID study suggested that assuming perfect laboratory test performance can lead to an inaccurate inference of the incidence. Our flexible, pragmatic method can be extended to a variety of disease and study settings.


Assuntos
COVID-19 , Pandemias , Humanos , Funções Verossimilhança , Incidência , Estudos Longitudinais , Simulação por Computador , COVID-19/epidemiologia
12.
AIDS ; 38(3): 329-337, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37861675

RESUMO

OBJECTIVES: To describe the clinical and virologic characteristics of HIV-HBV coinfection, including the predictors of high maternal HBV viral load in pregnant women with HIV in sub-Saharan Africa (SSA). METHODS: HPTN 046 was a HIV perinatal transmission clinical trial evaluating infant nevirapine vs. placebo. Women-infant pairs ( n  = 2016) were enrolled in SSA from 2007 to 2010; 1579 (78%) received antiretrovirals (ARV). Maternal delivery samples were retrospectively tested for hepatitis B surface antigen (HBsAg), and if positive, were tested for hepatitis B e antigen (HBeAg) and HBV viral load (VL). High HBV VL was defined as ≥10 6  IU/ml. RESULTS: Overall, 4.4% (88/2016) had HBV co-infection, with geographic variability ranging from 2.4% to 8.7% ( P  < 0.0001); 25% (22/88) were HBeAg positive with prevalence in countries ranging from 10.5% to 39%. Fifty-two percentage (40/77) of those with HBV received ARV, the majority (97%) received 3TC as the only HBV active agent. HBeAg positivity was associated with high maternal HBV VL, odds ratio (OR) 37.0, 95% confidence interval (CI) 5.4-252.4. Of those with high HBV VL, 40% (4/10) were receiving HBV active drugs (HBV-ARV). HBV drug resistance occurred in 7.5% (3/40) receiving HBV-ARV. CONCLUSIONS: In SSA, HBV co-infection is common in pregnant women with HIV. HBsAg and HBeAg prevalence vary widely by country in this clinical trial cohort. HBeAg is a surrogate for high HBV viral load. HBV drug resistance occurred in 7.5% receiving HBV-ARV with lamivudine as the only HBV active agent. These findings reinforce the importance of HBsAg screening and early treatment with two active agents for HBV.


Assuntos
Coinfecção , Infecções por HIV , Hepatite B , Feminino , Humanos , Lactente , Gravidez , África Subsaariana/epidemiologia , Antirretrovirais/uso terapêutico , Coinfecção/tratamento farmacológico , DNA Viral , Hepatite B/tratamento farmacológico , Hepatite B/epidemiologia , Antígenos E da Hepatite B/uso terapêutico , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B/genética , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Lamivudina/uso terapêutico , Estudos Retrospectivos , Carga Viral
13.
Pediatr Res ; 95(2): 480-487, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37940663

RESUMO

The twenty-first century has been marked by a surge in viral epidemics and pandemics, highlighting the global health challenge posed by emerging and re-emerging pediatric viral diseases. This review article explores the complex dynamics contributing to this challenge, including climate change, globalization, socio-economic interconnectedness, geopolitical tensions, vaccine hesitancy, misinformation, and disparities in access to healthcare resources. Understanding the interactions between the environment, socioeconomics, and health is crucial for effectively addressing current and future outbreaks. This scoping review focuses on emerging and re-emerging viral infectious diseases, with an emphasis on pediatric vulnerability. It highlights the urgent need for prevention, preparedness, and response efforts, particularly in resource-limited communities disproportionately affected by climate change and spillover events. Adopting a One Health/Planetary Health approach, which integrates human, animal, and ecosystem health, can enhance equity and resilience in global communities. IMPACT: We provide a scoping review of emerging and re-emerging viral threats to global pediatric populations This review provides an update on current pediatric viral threats in the context of the COVID-19 pandemic This review aims to sensitize clinicians, epidemiologists, public health practitioners, and policy stakeholders/decision-makers to the role these viral diseases have in persistent pediatric morbidity and mortality.


Assuntos
COVID-19 , Doenças Transmissíveis , Animais , Humanos , Criança , Pandemias , Ecossistema , Surtos de Doenças/prevenção & controle , Saúde Global
14.
Clin Infect Dis ; 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37963102

RESUMO

BACKGROUND: Nirmatrelvir/ritonavir (N/R) reduces severe outcomes among patients with COVID-19; however, rebound after treatment has been reported. We compared symptom and viral dynamics in community-based individuals with COVID-19 who completed N/R and similar untreated individuals. METHODS: We identified symptomatic participants who tested SARS-CoV-2 positive and were N/R eligible from a COVID-19 household transmission study: index cases from ambulatory settings and their households were enrolled, collecting daily symptoms, medication use, and respiratory specimens for quantitative PCR for 10 days, March 2022-May 2023. Participants who completed N/R (treated) were propensity score matched to untreated participants. We compared symptom rebound, viral load (VL) rebound, average daily symptoms, and average daily VL by treatment status measured after N/R completion or, if untreated, seven days after symptom onset. RESULTS: Treated (n=130) and untreated participants (n=241) had similar baseline characteristics. After treatment completion, treated participants had greater occurrence of symptom rebound (32% vs 20%; p=0.009) and VL rebound (27% vs 7%; p<0.001). Average daily symptoms were lower among treated participants compared to untreated participants without symptom rebound (1.0 vs 1.6; p<0.01), but not statistically lower with symptom rebound (3.0 vs 3.4; p=0.5). Treated participants had lower average daily VLs without VL rebound (0.9 vs 2.6; p<0.01), but not statistically lower with VL rebound (4.8 vs 5.1; p=0.7). CONCLUSIONS: Individuals who completed N/R experienced fewer symptoms and lower VL but were more likely to have rebound compared to untreated individuals. Providers should still prescribe N/R, when indicated, and communicate possible increased rebound risk to patients.

15.
NPJ Vaccines ; 8(1): 137, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37749086

RESUMO

There is an increasing burden of circulating vaccine-derived polioviruses (cVDPVs) due to the continued use of oral poliovirus vaccine (OPV). However, the informativeness of routine OPV VP1 sequencing for the early identification of viruses carrying virulence-associated reversion mutations has not been directly evaluated in a controlled setting. We prospectively collected 15,331 stool samples to track OPV shedding from children receiving OPV and their contacts for ten weeks following an immunization campaign in Veracruz State, Mexico and sequenced VP1 genes from 358 samples. We found that OPV was genetically unstable and evolves at an approximately clocklike rate that varies across serotypes and by vaccination status. Overall, 61% (11/18) of OPV-1, 71% (34/48) OPV-2, and 96% (54/56) OPV-3 samples with available data had evidence of a reversion at the key 5' UTR attenuating position and 28% (13/47) of OPV-1, 12% (14/117) OPV-2, and 91% (157/173) OPV-3 of Sabin-like viruses had ≥1 known reversion mutations in the VP1 gene. Our results are consistent with previous work documenting rapid reversion to virulence of OPV and underscores the need for intensive surveillance following OPV use.

16.
Ann Epidemiol ; 86: 1-7, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37524216

RESUMO

PURPOSE: In an effort to decrease transmission during the first years of the COVID-19 pandemic, public health officials encouraged masking, social distancing, and working from home, and restricted travel. However, many studies of the effectiveness of these measures had significant methodologic limitations. In this analysis, we used data from the TrackCOVID study, a longitudinal cohort study of a population-based sample of 3846 adults in the San Francisco Bay Area, to evaluate the association between self-reported protective behaviors and incidence of SARS-CoV-2 infection. METHODS: Participants without SARS-CoV2 infection were enrolled from August to December 2020 and followed monthly with testing and surveys (median of four visits). RESULTS: A total of 118 incident infections occurred (3.0% of participants). At baseline, 80.0% reported always wearing a mask; 56.0% avoided contact with nonhousehold members some/most of the time; 9.6% traveled outside the state; and 16.0% worked 20 or more hours per week outside the home. Factors associated with incident infection included being Black or Latinx, having less than a college education, and having more household residents. The only behavioral factor associated with incident infection was working outside the home (adjusted hazard ratio 1.62, 95% confidence interval 1.02-2.59). CONCLUSIONS: Focusing on protecting people who cannot work from home could help prevent infections during future waves of COVID-19, or future pandemics from respiratory viruses. This focus must be balanced with the known importance of directing resources toward those at risk of severe infections.


Assuntos
COVID-19 , Adulto , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , SARS-CoV-2 , Pandemias/prevenção & controle , Estudos Longitudinais , RNA Viral , São Francisco/epidemiologia , Estudos de Coortes
17.
ACS Sens ; 8(6): 2309-2318, 2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37224474

RESUMO

We adapted an existing, spaceflight-proven, robust "electronic nose" (E-Nose) that uses an array of electrical resistivity-based nanosensors mimicking aspects of mammalian olfaction to conduct on-site, rapid screening for COVID-19 infection by measuring the pattern of sensor responses to volatile organic compounds (VOCs) in exhaled human breath. We built and tested multiple copies of a hand-held prototype E-Nose sensor system, composed of 64 chemically sensitive nanomaterial sensing elements tailored to COVID-19 VOC detection; data acquisition electronics; a smart tablet with software (App) for sensor control, data acquisition and display; and a sampling fixture to capture exhaled breath samples and deliver them to the sensor array inside the E-Nose. The sensing elements detect the combination of VOCs typical in breath at parts-per-billion (ppb) levels, with repeatability of 0.02% and reproducibility of 1.2%; the measurement electronics in the E-Nose provide measurement accuracy and signal-to-noise ratios comparable to benchtop instrumentation. Preliminary clinical testing at Stanford Medicine with 63 participants, their COVID-19-positive or COVID-19-negative status determined by concomitant RT-PCR, discriminated between these two categories of human breath with a 79% correct identification rate using "leave-one-out" training-and-analysis methods. Analyzing the E-Nose response in conjunction with body temperature and other non-invasive symptom screening using advanced machine learning methods, with a much larger database of responses from a wider swath of the population, is expected to provide more accurate on-the-spot answers. Additional clinical testing, design refinement, and a mass manufacturing approach are the main steps toward deploying this technology to rapidly screen for active infection in clinics and hospitals, public and commercial venues, or at home.


Assuntos
COVID-19 , Nanoestruturas , Compostos Orgânicos Voláteis , Animais , Humanos , Nariz Eletrônico , Reprodutibilidade dos Testes , COVID-19/diagnóstico , Testes Respiratórios/métodos , Compostos Orgânicos Voláteis/análise , Mamíferos
19.
medRxiv ; 2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36993386

RESUMO

There is an increasing burden of circulating vaccine-derived polioviruses (cVDPVs) due to the continued use of oral poliovirus vaccine (OPV). However, the informativeness of routine OPV VP1 sequencing for the early identification of viruses carrying virulence-associated reversion mutations has not been directly evaluated in a controlled setting. We prospectively collected 15,331 stool samples to track OPV shedding from vaccinated children and their contacts for ten weeks following an immunization campaign in Veracruz State, Mexico and sequenced VP1 genes from 358 samples. We found that OPV was genetically unstable and evolves at an approximately clocklike rate that varies across serotypes and by vaccination status. Alarmingly, 28% (13/47) of OPV-1, 12% (14/117) OPV-2, and 91% (157/173) OPV-3 of Sabin-like viruses had ≥1 known reversion mutation. Our results suggest that current definitions of cVDPVs may exclude circulating virulent viruses that pose a public health risk and underscore the need for intensive surveillance following OPV use.

20.
Open Forum Infect Dis ; 10(2): ofad001, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36751652

RESUMO

Background: The limited variation observed among severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) consensus sequences makes it difficult to reconstruct transmission linkages in outbreak settings. Previous studies have recovered variation within individual SARS-CoV-2 infections but have not yet measured the informativeness of within-host variation for transmission inference. Methods: We performed tiled amplicon sequencing on 307 SARS-CoV-2 samples, including 130 samples from 32 individuals in 14 households and 47 longitudinally sampled individuals, from 4 prospective studies with household membership data, a proxy for transmission linkage. Results: Consensus sequences from households had limited diversity (mean pairwise distance, 3.06 single-nucleotide polymorphisms [SNPs]; range, 0-40). Most (83.1%, 255 of 307) samples harbored at least 1 intrahost single-nucleotide variant ([iSNV] median, 117; interquartile range [IQR], 17-208), above a minor allele frequency threshold of 0.2%. Pairs in the same household shared significantly more iSNVs (mean, 1.20 iSNVs; 95% confidence interval [CI], 1.02-1.39) than did pairs in different households infected with the same viral clade (mean, 0.31 iSNVs; 95% CI, .28-.34), a signal that decreases with increasingly stringent minor allele frequency thresholds. The number of shared iSNVs was significantly associated with an increased odds of household membership (adjusted odds ratio, 1.35; 95% CI, 1.23-1.49). However, the poor concordance of iSNVs detected across sequencing replicates (24.8% and 35.0% above a 0.2% and 1% threshold) confirms technical concerns that current sequencing and bioinformatic workflows do not consistently recover low-frequency within-host variants. Conclusions: Shared within-host variation may augment the information in consensus sequences for predicting transmission linkages. Improving sensitivity and specificity of within-host variant identification will improve the informativeness of within-host variation.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA