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1.
medRxiv ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38946994

RESUMO

Introduction: Few studies have evaluated baseline predictors of clinical outcomes among people with HIV starting antiretroviral therapy (ART) in the modern era of rapid ART initiation. Methods: We conducted a secondary analysis of a randomized controlled trial of two rapid treatment initiation strategies for people with treatment-naïve HIV and tuberculosis symptoms at an urban clinic in Haiti. We used logistic regression models to assess associations between baseline characteristics and (1) retention in care at 48 weeks, (2) HIV viral load suppression at 48 weeks (among participants who underwent viral load testing), and (3) all-cause mortality. Results: 500 participants were enrolled in the study 11/2017-1/2020. Eighty-eight (18%) participants were diagnosed with tuberculosis, and ART was started in 494 (99%). After adjustment, less than secondary education (adjusted odds ratio [AOR] 0.21, 95% CI 0.10-0.46), dolutegravir initiation (AOR 2.57, 95% CI 1.22-5.43), age (AOR 1.42 per 10-year increase, 95% CI 1.01-1.99), and tuberculosis diagnosis (AOR 3.92, 95% CI 1.36-11.28) were significantly associated with retention. Age (AOR 1.36, 95% CI 1.05-1.75), dolutegravir initiation (AOR 1.75, 95% CI 1.07-2.85), and tuberculosis diagnosis (AOR 0.50, 95% CI 0.28-0.89) were associated with viral suppression. Higher CD4 cell count at enrollment (unadjusted odds ratio [OR] 0.69, 95% CI 0.55-0.87) and anemia (OR 4.86, 95% CI 1.71-13.81) were associated with mortality. Conclusions: We identified sociodemographic, treatment-related, clinical, and laboratory-based predictors of clinical outcomes. These characteristics may serve as markers of sub-populations that could benefit from additional interventions to support treatment success after rapid treatment initiation.

2.
AIDS Care ; : 1-7, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38961850

RESUMO

Little is known about the pre-implementation context for a preventive HIV vaccine. We conducted interviews of individuals in Philadelphia recruited at Penn clinics and community-based organizations serving LGBTQ-identifying persons of color who 1) were cisgender men who had sex with men, or were transgender-identified, 2) had a sexually transmitted infection in the last 12 months, or sex with multiple partners within the last two weeks. We assessed acceptability, facilitators, and barriers to a hypothetical HIV vaccine using an integrated analysis approach. We interviewed 30 individuals between 2/2023-9/2023. Participants were supportive of an HIV vaccine and reported that they would strongly consider receiving one if one became available. Participants contextualized a hypothetical vaccine with the current HIV prevention context, primarily pre-exposure prophylaxis (PrEP), indicating that they would evaluate any future vaccine in comparison to their experience within the PrEP landscape.Reported facilitators for a hypothetical HIV vaccine included vaccine access, knowledge, and understanding; their risk for HIV exposure; and perceived benefits of the vaccine. Barriers included lack of understanding of the purpose of a vaccine, stigma surrounding HIV and sexual practices that may surface towards people who seek vaccination, and potential issues with effectiveness, side effects, or lack of availability.

3.
Clin Infect Dis ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38888419

RESUMO

BACKGROUND: Tuberculosis is a leading cause of death worldwide, and food insecurity is known to negatively influence health outcomes through multiple pathways. Few studies have interrogated the relationship between food insecurity and tuberculosis outcomes, particularly independent of nutrition. METHODS: We conducted a prospective cohort study of adults initiating first-line treatment for clinically suspected or microbiologically confirmed drug-sensitive tuberculosis at a rural referral center in Haiti. We administered a baseline questionnaire, collected clinical data, and analyzed laboratory samples. We used logistic regression models to estimate the relationship between household food insecurity (Household Hunger Scale) and treatment failure or death. We accounted for exclusion of patients lost to follow-up using inverse probability of censoring weighting and adjusted for measured confounders and nutritional status using inverse probability of treatment weighting. RESULTS: We enrolled 257 participants (37% female) between May 2020 and March 2023 with a median age (interquartile range) of 35 (25-45) years. Of these, 105 (41%) had no hunger in the household, 104 (40%) had moderate hunger in the household, and 48 (19%) had severe hunger in the household. Eleven participants (4%) died, and 6 (3%) had treatment failure. After adjustment, food insecurity was significantly associated with subsequent treatment failure or death (odds ratio 5.78 [95% confidence interval, 1.20-27.8]; P = .03). CONCLUSIONS: Household food insecurity at tuberculosis treatment initiation was significantly associated with death or treatment failure after accounting for loss to follow-up, measured confounders, and nutritional status. In addition to the known importance of undernutrition, our findings indicate that food insecurity independently affects tuberculosis treatment outcomes in Haiti.

4.
medRxiv ; 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38585968

RESUMO

Behavioral economics research suggests poverty may influence behavior by reducing mental bandwidth, increasing future discounting, and increasing risk aversion. It is plausible that these decision-making processes are further impaired in the context of HIV or pregnancy. In this cross-sectional study of 86 low-income women in Philadelphia, multivariable models showed that HIV was associated with decreased mental bandwidth (one of two measures) and lower risk aversion. Pregnancy was not associated with any decision-making factors. Viral suppression was associated with greater mental bandwidth (one of two measures), and antenatal care engagement with lower future discounting. Anti-poverty interventions may be particularly beneficial to improve health behaviors in the context of HIV.

5.
medRxiv ; 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38463947

RESUMO

Lack of adherence to antiretroviral therapy (ART) and poor retention in care are significant barriers to ending HIV epidemics. Treatment adherence support (TAS) effectiveness may be constrained by limited awareness and understanding of the benefits of ART, particularly the concepts of treatment as prevention and Undetectable=Untransmittable (U=U), for which substantial knowledge gaps persist. We used mixed methods to evaluate a straightforward visual and tactile tool, the B-OK Bottles ("B-OK"), that incorporates human-centered design and behavioral economics principles and is designed to change and strengthen mental models about HIV disease progression and transmission. We enrolled 118 consenting adults living with HIV who were clients of medical case managers at one of four case management agencies in Philadelphia. All participants completed a pre-intervention survey, a B-OK intervention, and a post-intervention survey. A subset (N=52) also completed qualitative interviews before (N=20) or after (N=32) B-OK. Participants had a median age of 55 years (IQR 47-60), about two-thirds were male sex (N=77, 65%), nearly three-quarters identified as non-Hispanic Black (N=85, 72%), and almost all reported receiving ART (N=116, 98%). Exposure to B-OK was associated with improved awareness and understanding of HIV terminology, changes in attitudes about HIV treatment, and increased intention to rely on HIV treatment for transmission prevention. Insights from qualitative interviews aligned with the quantitative findings as respondents expressed a better understanding of U=U and felt that B-OK clearly explained concepts of HIV treatment and prevention. These findings provide a strong rationale to further evaluate the potential for B-OK to improve TAS for PLWH.

6.
J Acquir Immune Defic Syndr ; 95(5): 494-504, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38346410

RESUMO

BACKGROUND: Food insecurity and undernutrition are related but distinct concepts contributing to poor HIV and tuberculosis outcomes. Pathways linking them with immunologic profile, which may relate to clinical outcomes, remain understudied. METHODS: We analyzed data from a cohort study of 165 antiretroviral therapy (ART)-naïve adults with advanced HIV and newly diagnosed tuberculosis in Botswana from 2009 to 2013. Twenty-nine plasma biomarkers were measured pre-ART and 4 weeks post-ART initiation. We used principal components analysis (PCA) and multivariable linear regression models to assess relationships between immunological profiles and food insecurity (based on the Household Food Insecurity Access Scale), undernutrition (body mass index <18.5 kg/m 2 ), and clinical outcomes. RESULTS: PCA identified 5 principal components with eigenvalues >1. After adjustment, food insecurity was associated with PC3 pre-ART (0.19 per increased category of severity, 95% CI: 0.02 to 0.36) and post-ART (0.24, 95% CI: 0.07 to 0.41). PC3 was driven by higher levels of IFN-α, IFN-γ, interleukin (IL)-12p40, vascular endothelial growth factor, IL-1α, and IL-8 and decreased concentrations of IL-3. Undernutrition was associated with PC5 post-ART (0.49, 95% CI: 0.16 to 0.82). PC5 was driven by higher levels of IL-8, MIP-1α, IL-6, and IL-10 and decreased concentrations in IP-10 and IFN-α. Post-ART PC3 (4.3 percentage point increased risk per increased score of 1, 95% CI: 0.3 to 8.9) and post-ART PC5 (4.8, 95% CI: 0.6 to 8.9) were associated with death in adjusted models. DISCUSSION: We identified 2 distinct immunologic profiles associated with food insecurity, undernutrition, and clinical outcomes in patients with advanced HIV and tuberculosis. Different pathophysiologic processes may link food insecurity and undernutrition with poor outcomes in this vulnerable patient population. Future studies should assess the impact of improving food access and intake on immune function and clinical outcomes.


Assuntos
Infecções por HIV , Desnutrição , Tuberculose , Adulto , Humanos , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Estudos de Coortes , Interleucina-8/uso terapêutico , Fator A de Crescimento do Endotélio Vascular/uso terapêutico , Desnutrição/complicações , Desnutrição/epidemiologia , Tuberculose/complicações , Insegurança Alimentar , Abastecimento de Alimentos
7.
Nat Rev Microbiol ; 22(2): 75-88, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38114838

RESUMO

The clinical implications of COVID-19 have changed since SARS-CoV-2 first emerged in humans. The current high levels of population immunity, due to prior infection and/or vaccination, have been associated with a vastly decreased overall risk of severe disease. Some people, particularly those with immunocompromising conditions, remain at risk for severe outcomes. Through the course of the pandemic, variants with somewhat different symptom profiles from the original SARS-CoV-2 virus have emerged. The management of COVID-19 has also changed since 2020, with the increasing availability of evidence-based treatments in two main classes: antivirals and immunomodulators. Selecting the appropriate treatment(s) for patients with COVID-19 requires a deep understanding of the evidence and an awareness of the limitations of applying data that have been largely based on immune-naive populations to patients today who most likely have vaccine-derived and/or infection-derived immunity. In this Review, we provide a summary of the clinical manifestations and approaches to caring for adult patients with COVID-19 in the era of vaccine availability and the dominance of the Omicron subvariants, with a focus on the management of COVID-19 in different patient groups, including immunocompromised, pregnant, vaccinated and unvaccinated patients.


Assuntos
COVID-19 , Vacinas , Adulto , Feminino , Gravidez , Humanos , Imunidade Coletiva , SARS-CoV-2 , Vacinação , Progressão da Doença
8.
JAMA Health Forum ; 4(8): e232511, 2023 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-37566430

RESUMO

This cross-sectional study evaluates associations between changes in Supplemental Nutrition Assistance Program emergency allotments and food insufficiency, a severe form of food insecurity characterized by recent food inadequacy.


Assuntos
Assistência Alimentar , Alimentos , Pobreza
9.
Ann Glob Health ; 89(1): 44, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37362826

RESUMO

Background: The number of global health (GH) physician training programs in the United States has increased in the past decade. Few studies have explored the demographics of individuals in these programs, the impact of global health training on career development, and specific factors associated with whether graduates achieve a career in global health. Objectives: We aimed to describe characteristics of program graduates and quantify which previously identified factors were associated with achieving a self-defined career in GH among a cohort of graduates from one GH post-graduate training program in a highly resourced academic medical center in the United States between 2003 and 2018. Methods: We conducted a cross-sectional survey and analyzed differences between participants who self-identified as having a career in GH compared to those who did not. Findings: Among 59 individuals invited to participate, 53 (89.9%) responded to the survey. Having a GH mentor was associated with having a career in GH (OR 10.3; p = 0.004). Those who had a GH career were more likely to have a clearly-defined career path (p = 0.03), have institutional support in their current job (p = 0.00006), be able to manage the split between their GH and non-GH work (p = 0.0001), find funding to achieve their objectives in GH (p = 0.01), invest in their personal and family life (p = 0.05), and split work abroad and domestically with few challenges (p = 0.01). Conclusions: We present sociodemographic and career characteristics for graduates from a GH training program in a highly resourced academic medical center in the United States. Mentorship, institutional support, funding, ability to balance GH with non-GH work, and time spent domestically or abroad are key factors associated with successful careers in GH. If institutional funding is allocated to strengthen these aspects of GH training, we anticipate more sustained GH career development.


Assuntos
Internato e Residência , Humanos , Estados Unidos , Saúde Global , Estudos Transversais , Escolha da Profissão , Educação de Pós-Graduação em Medicina
11.
Nature ; 618(7965): 575-582, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37258664

RESUMO

Poverty is an important social determinant of health that is associated with increased risk of death1-5. Cash transfer programmes provide non-contributory monetary transfers to individuals or households, with or without behavioural conditions such as children's school attendance6,7. Over recent decades, cash transfer programmes have emerged as central components of poverty reduction strategies of many governments in low- and middle-income countries6,7. The effects of these programmes on adult and child mortality rates remains an important gap in the literature, however, with existing evidence limited to a few specific conditional cash transfer programmes, primarily in Latin America8-14. Here we evaluated the effects of large-scale, government-led cash transfer programmes on all-cause adult and child mortality using individual-level longitudinal mortality datasets from many low- and middle-income countries. We found that cash transfer programmes were associated with significant reductions in mortality among children under five years of age and women. Secondary heterogeneity analyses suggested similar effects for conditional and unconditional programmes, and larger effects for programmes that covered a larger share of the population and provided larger transfer amounts, and in countries with lower health expenditures, lower baseline life expectancy, and higher perceived regulatory quality. Our findings support the use of anti-poverty programmes such as cash transfers, which many countries have introduced or expanded during the COVID-19 pandemic, to improve population health.


Assuntos
Mortalidade da Criança , Países em Desenvolvimento , Mortalidade , Pobreza , Adulto , Pré-Escolar , Feminino , Humanos , Mortalidade da Criança/tendências , COVID-19/economia , COVID-19/epidemiologia , Países em Desenvolvimento/economia , Pobreza/economia , Pobreza/prevenção & controle , Pobreza/estatística & dados numéricos , Expectativa de Vida , Gastos em Saúde/estatística & dados numéricos , Saúde Pública/métodos , Saúde Pública/estatística & dados numéricos , Saúde Pública/tendências , Mortalidade/tendências
12.
AIDS Behav ; 27(10): 3460-3467, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37036593

RESUMO

Despite evidence supporting HIV pre-exposure prophylaxis (PrEP) effectiveness, very few women with opioid use disorder (OUD) take PrEP. Interventions that improve medication assisted treatment (MAT) uptake and adherence may also be beneficial for PrEP. The reSET-O mobile phone app is a component of the evidence-based Therapeutic Education System, which improves retention and abstinence for people with OUD. To better understand use of this mobile health tool as a support for PrEP among women with OUD, pre-implementation contextual inquiry is needed. Therefore, we set out to assess target user characteristics, implementation barriers, feasibility, and acceptability of reSET-O. We recruited women with OUD receiving care from a community-based organization in Philadelphia to complete semi-structured interviews. All participants were prescribed reSET-O. We interviewed 20 participants (average age 37 years; 70% white, 15% Hispanic, 5% Black) from 5/2021 to 2/2022. We used an integrated analysis approach combining modified grounded theory and implementation science constructs. Half reported recent injection drug use, and 6 were taking buprenorphine. Mental health symptoms were common, and half described engaging in transactional sex. The majority expressed strong interest in PrEP. Participants reported the app would be highly acceptable for PrEP and MAT adherence support, but only two redeemed the prescription. The most common barriers included phone and internet access. Our findings highlight potential implementation challenges for the use of such an app to support PrEP use in this population. Poor uptake of the app at follow-up indicates that initial prescription redemption is a major barrier to reSET-O implementation.


Assuntos
Telefone Celular , Infecções por HIV , Aplicativos Móveis , Transtornos Relacionados ao Uso de Opioides , Profilaxia Pré-Exposição , Humanos , Feminino , Adulto , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Infecções por HIV/epidemiologia , Estudos de Viabilidade
13.
PLoS Negl Trop Dis ; 17(2): e0010574, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36745661

RESUMO

BACKGROUND: Food insecurity has been independently associated with developing cholera and there is an inverse relationship between national food security and annual cholera incidence. However, the factors that mediate the risk of cholera among food insecure households remain largely unexplored. METHODOLOGY AND PRINCIPAL FINDINGS: In a cross-sectional survey of rural households in Haiti, we explored the role of food behaviors (i.e., dietary choices and food-handling practices) as mediators of cholera risk among food-insecure families. We generated a series of multivariable regression models to test hypothesized associations between the severity of food insecurity (measured by the Household Hunger Scale), hygiene and food behaviors, and history of severe, medically-attended cholera. Moderate household hunger (Adjusted Odds Ratio [AOR] 1.47, 95% Confidence Interval (CI) 1.05-2.04; p = 0.021) and severe hunger (AOR 2.45, 95% CI 1.45-4.15; p = 0.001) were positively associated with a history of severe, medically-attended cholera compared with little to no household hunger. Household hunger was positively associated with three behaviors: antacid use, consumption of leftover non-reheated food, and eating food and beverages prepared outside of the home (i.e., at a restaurant or from a vendor). Consumption of outside food items and antacid use were positively associated with a history of cholera. CONCLUSION: Our findings suggest that food behaviors may mediate the association between food insecurity and cholera and contribute to an understanding of how interventions could be designed to target food insecurity as part of cholera prevention and control.


Assuntos
Cólera , Humanos , Estudos Transversais , Cólera/epidemiologia , Antiácidos , Abastecimento de Alimentos , Insegurança Alimentar
14.
Clin Infect Dis ; 76(3): e319-e326, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35666508

RESUMO

BACKGROUND: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant has spread rapidly throughout the world since being identified in South Africa in November 2021. Few studies have assessed primary series and booster vaccine effectiveness against Omicron among US healthcare workers. METHODS: We conducted a test-negative case-control design to estimate BNT162b2 and mRNA1273 primary vaccination and booster effectiveness against SARS-CoV-2 infection and symptomatic coronavirus disease 2019 during an Omicron surge among employees of the University of Pennsylvania Health System. The study period was between 1 July 2021 and 5 April 2022. We defined the Delta period as 1 July to 12 December 2021 and the Omicron period as beginning 12 December 21. RESULTS: Our sample included 14 520 tests (2776 [19%] positive)-7422 (506 [7%] positive) during Delta and 7098 (2270 [32%] positive) during Omicron. Benchmarked against Delta, the vaccine effectiveness of 2 vaccine doses was lower during Omicron, with no significant protection against infection. Booster doses added significant protection, although they also showed reduced effectiveness during Omicron. Compared with findings in employees who had received 2 vaccine doses, 3 doses of BNT162b2 had a relative effectiveness of 50% (95% confidence interval, 42%-56%) during Omicron, relative to 78% (63%-87%) during Delta; 3 doses of mRNA1273 had a relative effectiveness of 56% (45%-65%) during Omicron, relative to 96% (82%-99%) during Delta. Restricting the sample to symptomatic tests yielded similar results to our primary analysis. After initial waning in BNT162b2 booster protection against infection, it remained largely stable for ≥16 weeks after vaccination. CONCLUSIONS: Our findings provide a strong rationale for boosters among healthcare workers in the Omicron era.


Assuntos
COVID-19 , Vacinas , Humanos , Vacina BNT162 , SARS-CoV-2 , COVID-19/prevenção & controle , Pessoal de Saúde , Vacina de mRNA-1273 contra 2019-nCoV , RNA , RNA Mensageiro
16.
Nat Hum Behav ; 6(10): 1362-1371, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35851840

RESUMO

Many countries have introduced cash transfer programmes as part of their poverty reduction and social protection strategies. These programmes have the potential to overcome drivers of HIV risk behaviours and usage of HIV services, but their overall effects on HIV-related outcomes remain unknown. Here we evaluate the effects of cash transfer programmes covering >5% of the impoverished population on country- and individual-level HIV-related outcomes in 42 countries with generalized epidemics. Cash transfer programmes were associated with a lower probability of sexually transmitted infections among females (odds ratio, 0.67; 95% confidence interval (CI), 0.50-0.91; P = 0.01), a higher probability of recent HIV testing among females (odds ratio, 2.61; 95% CI, 1.15-5.88; P = 0.02) and among males (odds ratio, 3.19; 95% CI, 2.45-4.15; P < 0.001), a reduction in new HIV infections (incidence rate ratio, 0.94; 95% CI, 0.89-0.99; P = 0.03) and delayed improvements in antiretroviral coverage (3%; 95% CI, 0.3-5.7 at year 2; P = 0.03) and AIDS-related deaths (incidence rate ratio, 0.91; 95% CI, 0.83-0.99 at year 2; P = 0.03). Anti-poverty programmes can play a greater role in achieving global targets for HIV prevention and treatment.


Assuntos
Infecções por HIV , Humanos , Masculino , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Política Pública , Pobreza
17.
Infect Dis Clin North Am ; 36(2): 267-293, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35636900

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) delta variant transmits much more rapidly than prior SARS-CoV-2 viruses. The primary mode of transmission is via short range aerosols that are emitted from the respiratory tract of an index case. There is marked heterogeneity in the spread of this virus, with 10% to 20% of index cases contributing to 80% of secondary cases, while most index cases have no subsequent transmissions. Vaccination, ventilation, masking, eye protection, and rapid case identification with contact tracing and isolation can all decrease the transmission of this virus.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/prevenção & controle , Humanos , Vacinação
18.
PLoS Med ; 19(5): e1003987, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35617363

RESUMO

BACKGROUND: Debate about the level of asymptomatic Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection continues. The amount of evidence is increasing and study designs have changed over time. We updated a living systematic review to address 3 questions: (1) Among people who become infected with SARS-CoV-2, what proportion does not experience symptoms at all during their infection? (2) What is the infectiousness of asymptomatic and presymptomatic, compared with symptomatic, SARS-CoV-2 infection? (3) What proportion of SARS-CoV-2 transmission in a population is accounted for by people who are asymptomatic or presymptomatic? METHODS AND FINDINGS: The protocol was first published on 1 April 2020 and last updated on 18 June 2021. We searched PubMed, Embase, bioRxiv, and medRxiv, aggregated in a database of SARS-CoV-2 literature, most recently on 6 July 2021. Studies of people with PCR-diagnosed SARS-CoV-2, which documented symptom status at the beginning and end of follow-up, or mathematical modelling studies were included. Studies restricted to people already diagnosed, of single individuals or families, or without sufficient follow-up were excluded. One reviewer extracted data and a second verified the extraction, with disagreement resolved by discussion or a third reviewer. Risk of bias in empirical studies was assessed with a bespoke checklist and modelling studies with a published checklist. All data syntheses were done using random effects models. Review question (1): We included 130 studies. Heterogeneity was high so we did not estimate a mean proportion of asymptomatic infections overall (interquartile range (IQR) 14% to 50%, prediction interval 2% to 90%), or in 84 studies based on screening of defined populations (IQR 20% to 65%, prediction interval 4% to 94%). In 46 studies based on contact or outbreak investigations, the summary proportion asymptomatic was 19% (95% confidence interval (CI) 15% to 25%, prediction interval 2% to 70%). (2) The secondary attack rate in contacts of people with asymptomatic infection compared with symptomatic infection was 0.32 (95% CI 0.16 to 0.64, prediction interval 0.11 to 0.95, 8 studies). (3) In 13 modelling studies fit to data, the proportion of all SARS-CoV-2 transmission from presymptomatic individuals was higher than from asymptomatic individuals. Limitations of the evidence include high heterogeneity and high risks of selection and information bias in studies that were not designed to measure persistently asymptomatic infection, and limited information about variants of concern or in people who have been vaccinated. CONCLUSIONS: Based on studies published up to July 2021, most SARS-CoV-2 infections were not persistently asymptomatic, and asymptomatic infections were less infectious than symptomatic infections. Summary estimates from meta-analysis may be misleading when variability between studies is extreme and prediction intervals should be presented. Future studies should determine the asymptomatic proportion of SARS-CoV-2 infections caused by variants of concern and in people with immunity following vaccination or previous infection. Without prospective longitudinal studies with methods that minimise selection and measurement biases, further updates with the study types included in this living systematic review are unlikely to be able to provide a reliable summary estimate of the proportion of asymptomatic infections caused by SARS-CoV-2. REVIEW PROTOCOL: Open Science Framework (https://osf.io/9ewys/).


Assuntos
COVID-19 , Infecções Assintomáticas/epidemiologia , COVID-19/epidemiologia , Humanos , Programas de Rastreamento , Estudos Prospectivos , SARS-CoV-2
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