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1.
Open Forum Infect Dis ; 10(7): ofad330, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37484899

RESUMO

Background: Over 870 000 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections have occurred among Veterans Health Administration users, and 24 000 have resulted in death. We examined early outcomes of SARS-CoV-2 infection in hospitalized veterans. Methods: In an ongoing, prospective cohort study, we enrolled veterans age ≥18 tested for SARS-CoV-2 and hospitalized at 15 Department of Veterans Affairs medical centers between February 2021 and June 2022. We estimated adjusted odds ratios (aORs), adjusted incidence rate ratios (aIRRs), and adjusted hazard ratios (aHRs) for maximum illness severity within 30 days of study entry (defined using the 4-category VA Severity Index for coronavirus disease 2019 [COVID-19]), as well as length of hospitalization and rehospitalization within 60 days, in relationship with demographic characteristics, Charlson comorbidity index (CCI), COVID-19 vaccination, and calendar period of enrollment. Results: The 542 participants included 329 (61%) who completed a primary vaccine series (with or without booster; "vaccinated"), 292 (54%) enrolled as SARS-CoV-2-positive, and 503 (93%) men, with a mean age of 64.4 years. High CCI scores (≥5) occurred in 61 (44%) vaccinated and 29 (19%) unvaccinated SARS-CoV-2-positive participants. Severe illness or death occurred in 29 (21%; 6% died) vaccinated and 31 (20%; 2% died) unvaccinated SARS-CoV-2-positive participants. SARS-CoV-2-positive inpatients per unit increase in CCI had greater multivariable-adjusted odds of severe illness (aOR, 1.21; 95% CI, 1.01-1.45), more hospitalization days (aIRR, 1.06; 95% CI, 1.03-1.10), and rehospitalization (aHR, 1.07; 95% CI, 1.01-1.12). Conclusions: In a cohort of hospitalized US veterans with SARS-CoV-2 infection, those with a higher CCI had more severe COVID-19 illness, more hospital days, and rehospitalization, after adjusting for vaccination status, age, sex, and calendar period.

2.
Clin Infect Dis ; 76(7): 1180-1187, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36433685

RESUMO

BACKGROUND: An exploratory household transmission study was nested in SPECTRA, the phase 2/3 efficacy study of the adjuvanted recombinant protein-based COVID-19 vaccine SCB-2019. We compared the occurrence of confirmed COVID-19 infections between households and household contacts of infected SPECTRA placebo or SCB-2019 recipients. METHODS: SPECTRA participants at 8 study sites in the Philippines who developed real-time reverse transcriptase-polymerase chain reaction (rRT-PCR)-confirmed COVID-19 were contacted by a study team blinded to assignment of index cases to vaccine or placebo groups to enroll in this household transmission study. Enrolled households and household contacts were monitored for 3 weeks using rRT-PCR and anti-SARS-CoV-2 N-antigen IgG/IgM testing to detect new COVID-19 infections. RESULTS: One hundred fifty-four eligible COVID-19 index cases (51 vaccinees, 103 placebo) were included. The secondary attack rate per household for symptomatic COVID-19 infection was 0.76% (90% CI: .15-3.90%) if the index case was an SCB-2019 vaccinee compared with 5.88% (90% CI: 3.20-10.8%) for placebo index cases, a relative risk reduction (RRR) of 79% (90% CI: -28% to 97%). The RRR of symptomatic COVID-19 per household member was similar: 84% (90% CI: 28-97%). The impact on attack rates in household members if index cases were symptomatic (n = 130; RRR = 80%; 90% CI: 7-96%) or asymptomatic (n = 24; RRR = 100%; 90% CI: -76% to 100%) was measurable but the low numbers undermine the clinical significance. CONCLUSIONS: In this prospective household contact study vaccination with SCB-2019 reduced SARS-CoV-2 transmission compared with placebo in households and in household members independently of whether or not index cases were symptomatic.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19 , SARS-CoV-2 , Estudos Prospectivos , Filipinas/epidemiologia , Vacinação , Anticorpos Antivirais
3.
Am Surg ; 89(4): 996-1002, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34761682

RESUMO

BACKGROUND: Previous investigations have shown a positive association between hospital volume of operations and clinical outcomes. However, it is unclear whether such relationships also apply to emergency surgery. We sought to examine the association between hospital case volume and inpatient mortality for 7 common emergency general surgery (EGS) operations among geriatric patients. METHODS: This is a population based retrospective cohort study using the Centers of Medicare and Medicaid Services (CMS) Limited Dataset Files (LDS) from 2011 to 2013. The 7 most common emergency surgeries included (1) partial colectomy, (2) small-bowel resection (SBR), (3) cholecystectomy, (4) appendectomy, (5) lysis of adhesions (LOA), (6) operative management of peptic ulcer disease (PUD), and (7) laparotomy with the primary outcome being inpatient mortality. Risk-adjusted inpatient mortality was plotted against operative volume. Subsequently an operative volume threshold was calculated using a best fit regression method. Based on these estimates, high- and low-volume hospitals were compared to examine significance of outcomes. Significance was defined as P-value < .05. RESULTS: The final cohort comprised of 414 779 patients from 3994 hospitals. The standardized mortality ratio (SMR) for high-volume centers were lower in 6 out of 8 surgeries examined. Small-bowel resection and partial colectomy operations had a significant decrease in mortality based on a volume threshold. CONCLUSION: We observed decreased mortality with higher surgical volume for small-bowel resection and partial colectomy operations. Such differences may be related to practice patterns during the perioperative period, as complications related to the perioperative care were significantly lower for high-volume centers.


Assuntos
Cirurgia Geral , Pacientes Internados , Humanos , Idoso , Estados Unidos , Estudos Retrospectivos , Emergências , Mortalidade Hospitalar , Medicare , Hospitais com Baixo Volume de Atendimentos , Colectomia
4.
J R Stat Soc Ser C Appl Stat ; 71(1): 70-90, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35721226

RESUMO

This study estimates the overall effect of two influenza vaccination programs consecutively administered in a cluster-randomized trial in western Senegal over the course of two influenza seasons from 2009-2011. We apply cutting-edge methodology combining social contact data with infection data to reduce bias in estimation arising from contamination between clusters. Our time-varying estimates reveal a reduction in seasonal influenza from the intervention and a nonsignificant increase in H1N1 pandemic influenza. We estimate an additive change in overall cumulative incidence (which was 6.13% in the control arm) of -0.68 percentage points during Year 1 of the study (95% CI: -2.53, 1.18). When H1N1 pandemic infections were excluded from analysis, the estimated change was -1.45 percentage points and was significant (95% CI, -2.81, -0.08). Because cross-cluster contamination was low (0-3% of contacts for most villages), an estimator assuming no contamination was only slightly attenuated (-0.65 percentage points). These findings are encouraging for studies carefully designed to minimize spillover. Further work is needed to estimate contamination - and its effect on estimation - in a variety of settings.

5.
Emerg Infect Dis ; 27(12): 3163-3165, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34808080

RESUMO

During the coronavirus disease pandemic, we observed a 6.4-fold increase in typhoid intestinal perforation incidence in Antananarivo, Madagascar. Thirteen perforations occurred within 6 months (February 2020-July 2020), compared with 13 perforations during the previous 41 months (August 2016-January 2020). The increase may be attributable to delayed healthcare seeking during the pandemic.


Assuntos
COVID-19 , Perfuração Intestinal , Febre Tifoide , Humanos , Perfuração Intestinal/epidemiologia , Perfuração Intestinal/etiologia , Madagáscar/epidemiologia , SARS-CoV-2 , Febre Tifoide/epidemiologia
6.
Elife ; 102021 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-34821551

RESUMO

Background: Transmission of respiratory pathogens such as SARS-CoV-2 depends on patterns of contact and mixing across populations. Understanding this is crucial to predict pathogen spread and the effectiveness of control efforts. Most analyses of contact patterns to date have focused on high-income settings. Methods: Here, we conduct a systematic review and individual-participant meta-analysis of surveys carried out in low- and middle-income countries and compare patterns of contact in these settings to surveys previously carried out in high-income countries. Using individual-level data from 28,503 participants and 413,069 contacts across 27 surveys, we explored how contact characteristics (number, location, duration, and whether physical) vary across income settings. Results: Contact rates declined with age in high- and upper-middle-income settings, but not in low-income settings, where adults aged 65+ made similar numbers of contacts as younger individuals and mixed with all age groups. Across all settings, increasing household size was a key determinant of contact frequency and characteristics, with low-income settings characterised by the largest, most intergenerational households. A higher proportion of contacts were made at home in low-income settings, and work/school contacts were more frequent in high-income strata. We also observed contrasting effects of gender across income strata on the frequency, duration, and type of contacts individuals made. Conclusions: These differences in contact patterns between settings have material consequences for both spread of respiratory pathogens and the effectiveness of different non-pharmaceutical interventions. Funding: This work is primarily being funded by joint Centre funding from the UK Medical Research Council and DFID (MR/R015600/1).


Infectious diseases, particularly those caused by airborne pathogens like SARS-CoV-2, spread by social contact, and understanding how people mix is critical in controlling outbreaks. To explore these patterns, researchers typically carry out large contact surveys. Participants are asked for personal information (such as gender, age and occupation), as well as details of recent social contacts, usually those that happened in the last 24 hours. This information includes, the age and gender of the contact, where the interaction happened, how long it lasted, and whether it involved physical touch. These kinds of surveys help scientists to predict how infectious diseases might spread. But there is a problem: most of the data come from high-income countries, and there is evidence to suggest that social contact patterns differ between places. Therefore, data from these countries might not be useful for predicting how infections spread in lower-income regions. Here, Mousa et al. have collected and combined data from 27 contact surveys carried out before the COVID-19 pandemic to see how baseline social interactions vary between high- and lower-income settings. The comparison revealed that, in higher-income countries, the number of daily contacts people made decreased with age. But, in lower-income countries, younger and older individuals made similar numbers of contacts and mixed with all age groups. In higher-income countries, more contacts happened at work or school, while in low-income settings, more interactions happened at home and people were also more likely to live in larger, intergenerational households. Mousa et al. also found that gender affected how long contacts lasted and whether they involved physical contact, both of which are key risk factors for transmitting airborne pathogens. These findings can help researchers to predict how infectious diseases might spread in different settings. They can also be used to assess how effective non-medical restrictions, like shielding of the elderly and workplace closures, will be at reducing transmissions in different parts of the world.


Assuntos
COVID-19/transmissão , Transmissão de Doença Infecciosa , Adolescente , Adulto , Idoso , COVID-19/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , SARS-CoV-2/isolamento & purificação , Adulto Jovem
7.
medRxiv ; 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34159341

RESUMO

BACKGROUND: Transmission of respiratory pathogens such as SARS-CoV-2 depends on patterns of contact and mixing across populations. Understanding this is crucial to predict pathogen spread and the effectiveness of control efforts. Most analyses of contact patterns to date have focussed on high-income settings. METHODS: Here, we conduct a systematic review and individual-participant meta-analysis of surveys carried out in low- and middle-income countries and compare patterns of contact in these settings to surveys previously carried out in high-income countries. Using individual-level data from 28,503 participants and 413,069 contacts across 27 surveys we explored how contact characteristics (number, location, duration and whether physical) vary across income settings. RESULTS: Contact rates declined with age in high- and upper-middle-income settings, but not in low-income settings, where adults aged 65+ made similar numbers of contacts as younger individuals and mixed with all age-groups. Across all settings, increasing household size was a key determinant of contact frequency and characteristics, but low-income settings were characterised by the largest, most intergenerational households. A higher proportion of contacts were made at home in low-income settings, and work/school contacts were more frequent in high-income strata. We also observed contrasting effects of gender across income-strata on the frequency, duration and type of contacts individuals made. CONCLUSIONS: These differences in contact patterns between settings have material consequences for both spread of respiratory pathogens, as well as the effectiveness of different non-pharmaceutical interventions. FUNDING: This work is primarily being funded by joint Centre funding from the UK Medical Research Council and DFID (MR/R015600/1).

8.
J Infect Dis ; 224(6): 967-975, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34153099

RESUMO

BACKGROUND: Early convalescent plasma transfusion may reduce mortality in patients with nonsevere coronavirus disease 2019 (COVID-19). METHODS: This study emulates a (hypothetical) target trial using observational data from a cohort of US veterans admitted to a Department of Veterans Affairs (VA) facility between 1 May and 17 November 2020 with nonsevere COVID-19. The intervention was convalescent plasma initiated within 2 days of eligibility. Thirty-day mortality was compared using cumulative incidence curves, risk differences, and hazard ratios estimated from pooled logistic models with inverse probability weighting to adjust for confounding. RESULTS: Of 11 269 eligible person-trials contributed by 4755 patients, 402 trials were assigned to the convalescent plasma group. Forty and 671 deaths occurred within the plasma and nonplasma groups, respectively. The estimated 30-day mortality risk was 6.5% (95% confidence interval [CI], 4.0%-9.7%) in the plasma group and 6.2% (95% CI, 5.6%-7.0%) in the nonplasma group. The associated risk difference was 0.30% (95% CI, -2.30% to 3.60%) and the hazard ratio was 1.04 (95% CI, .64-1.62). CONCLUSIONS: Our target trial emulation estimated no meaningful differences in 30-day mortality between nonsevere COVID-19 patients treated and untreated with convalescent plasma. Clinical Trials Registration. NCT04545047.


Assuntos
Transfusão de Componentes Sanguíneos , COVID-19/mortalidade , COVID-19/terapia , Imunização Passiva , Plasma , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Estados Unidos/epidemiologia , Veteranos , Adulto Jovem , Soroterapia para COVID-19
9.
Vaccines (Basel) ; 9(3)2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33808924

RESUMO

Typhoid fever remains a significant health problem in sub-Saharan Africa, with incidence rates of >100 cases per 100,000 person-years of observation. Despite the prequalification of safe and effective typhoid conjugate vaccines (TCV), some uncertainties remain around future demand. Real-life effectiveness data, which inform public health programs on the impact of TCVs in reducing typhoid-related mortality and morbidity, from an African setting may help encourage the introduction of TCVs in high-burden settings. Here, we describe a cluster-randomized trial to investigate population-level protection of TYPBAR-TCV®, a Vi-polysaccharide conjugated to a tetanus-toxoid protein carrier (Vi-TT) against blood-culture-confirmed typhoid fever, and the synthesis of health economic evidence to inform policy decisions. A total of 80 geographically distinct clusters are delineated within the Agogo district of the Asante Akim region in Ghana. Clusters are randomized to the intervention arm receiving Vi-TT or a control arm receiving the meningococcal A conjugate vaccine. The primary study endpoint is the total protection of Vi-TT against blood-culture-confirmed typhoid fever. Total, direct, and indirect protection are measured as secondary outcomes. Blood-culture-based enhanced surveillance enables the estimation of incidence rates in the intervention and control clusters. Evaluation of the real-world impact of TCVs and evidence synthesis improve the uptake of prequalified/licensed safe and effective typhoid vaccines in public health programs of high burden settings. This trial is registered at the Pan African Clinical Trial Registry, accessible at Pan African Clinical Trials Registry (ID: PACTR202011804563392).

10.
Clin Infect Dis ; 72(12): e959-e969, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33165566

RESUMO

BACKGROUND: We report results of years 2 and 3 of consecutive cluster-randomized controlled trials of trivalent inactivated influenza vaccine (IIV3) in Senegal. METHODS: We cluster-randomized (1:1) 20 villages to annual vaccination with IIV3 or inactivated poliovirus vaccine (IPV) of age-eligible residents (6 months-10 years). The primary outcome was total vaccine effectiveness against laboratory-confirmed influenza illness (LCI) among age-eligible children (modified intention-to-treat population [mITT]). Secondary outcomes were indirect (herd protection) and population (overall community) vaccine effectiveness. RESULTS: We vaccinated 74% of 12 408 age-eligible children in year 2 (June 2010-April 11) and 74% of 11 988 age-eligible children in year 3 (April 2011-December 2011) with study vaccines. Annual cumulative incidence of LCI was 4.7 (year 2) and 4.2 (year 3) per 100 mITT child vaccinees of IPV villages. In year 2, IIV3 matched circulating influenza strains. The total effectiveness was 52.8% (95% confidence interval [CI], 32.3-67.0), and the population effectiveness was 36.0% (95% CI, 10.2-54.4) against LCI caused by any influenza strain. The indirect effectiveness against LCI by A/H3N2 was 56.4% (95% CI, 39.0-68.9). In year 3, 74% of influenza detections were vaccine-mismatched to circulating B/Yamagata and 24% were vaccine-matched to circulating A/H3N2. The year 3 total effectiveness against LCI was -14.5% (95% CI, -81.2-27.6). Vaccine effectiveness varied by type/subtype of influenza in both years. CONCLUSIONS: IIV3 was variably effective against influenza illness in Senegalese children, with total and indirect vaccine effectiveness present during the year when all circulating strains matched the IIV3 formulation. CLINICAL TRIALS REGISTRATION: NCT00893906.


Assuntos
Vacinas contra Influenza , Influenza Humana , Criança , Humanos , Vírus da Influenza A Subtipo H3N2 , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Senegal/epidemiologia , Vacinas de Produtos Inativados
11.
Lancet Glob Health ; 8(8): e1081-e1089, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32710864

RESUMO

BACKGROUND: Cholera was introduced into Haiti in 2010. Since then, more than 820 000 cases and nearly 10 000 deaths have been reported. Oral cholera vaccine (OCV) is safe and effective, but has not been seen as a primary tool for cholera elimination due to a limited period of protection and constrained supplies. Regionally, epidemic cholera is contained to the island of Hispaniola, and the lowest numbers of cases since the epidemic began were reported in 2019. Hence, Haiti may represent a unique opportunity to eliminate cholera with OCV. METHODS: In this modelling study, we assessed the probability of elimination, time to elimination, and percentage of cases averted with OCV campaign scenarios in Haiti through simulations from four modelling teams. For a 10-year period from January 19, 2019, to Jan 13, 2029, we compared a no vaccination scenario with five OCV campaign scenarios that differed in geographical scope, coverage, and rollout duration. Teams used weekly department-level reports of suspected cholera cases from the Haiti Ministry of Public Health and Population to calibrate the models and used common vaccine-related assumptions, but other model features were determined independently. FINDINGS: Among campaigns with the same vaccination coverage (70% fully vaccinated), the median probability of elimination after 5 years was 0-18% for no vaccination, 0-33% for 2-year campaigns focused in the two departments with the highest historical incidence, 0-72% for three-department campaigns, and 35-100% for nationwide campaigns. Two-department campaigns averted a median of 12-58% of infections, three-department campaigns averted 29-80% of infections, and national campaigns averted 58-95% of infections. Extending the national campaign to a 5-year rollout (compared to a 2-year rollout), reduced the probability of elimination to 0-95% and the proportion of cases averted to 37-86%. INTERPRETATION: Models suggest that the probability of achieving zero transmission of Vibrio cholerae in Haiti with current methods of control is low, and that bolder action is needed to promote elimination of cholera from the region. Large-scale cholera vaccination campaigns in Haiti would offer the opportunity to synchronise nationwide immunity, providing near-term population protection while improvements to water and sanitation promote long-term cholera elimination. FUNDING: Bill & Melinda Gates Foundation, Global Good Fund, Institute for Disease Modeling, Swiss National Science Foundation, and US National Institutes of Health.


Assuntos
Vacinas contra Cólera/administração & dosagem , Cólera/prevenção & controle , Erradicação de Doenças/métodos , Programas de Imunização , Administração Oral , Cólera/epidemiologia , Haiti/epidemiologia , Humanos , Incidência , Modelos Biológicos , Vacinação/estatística & dados numéricos
12.
PLoS One ; 14(8): e0220443, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31386686

RESUMO

We present the first analysis of face-to-face contact network data from Niakhar, Senegal. Participants in a cluster-randomized influenza vaccine trial were interviewed about their contact patterns when they reported symptoms during their weekly household surveillance visit. We employ a negative binomial model to estimate effects of covariates on contact degree. We estimate the mean contact degree for asymptomatic Niakhar residents to be 16.5 (95% C.I. 14.3, 18.7) in the morning and 14.8 in the afternoon (95% C.I. 12.7, 16.9). We estimate that symptomatic people make 10% fewer contacts than asymptomatic people (95% C.I. 5%, 16%; p = 0.006), and those aged 0-5 make 33% fewer contacts than adults (95% C.I. 29%, 37%; p < 0.001). By explicitly modelling the partial rounding pattern observed in our data, we make inference for both the underlying (true) distribution of contacts as well as for the reported distribution. We created an estimator for homophily by compound (household) membership and estimate that 48% of contacts by symptomatic people are made to their own compound members in the morning (95% CI, 45%, 52%) and 60% in the afternoon/evening (95% CI, 56%, 64%). We did not find a significant effect of symptom status on compound homophily. We compare our findings to those from other countries and make design recommendations for future surveys.


Assuntos
Influenza Humana/transmissão , Modelos Estatísticos , Comportamento Social , Características da Família , Humanos , Vacinas contra Influenza , Influenza Humana/epidemiologia , Distância Psicológica , Vigilância em Saúde Pública , Senegal , Inquéritos e Questionários , Vacinação/estatística & dados numéricos
14.
Nat Commun ; 10(1): 1246, 2019 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-30886145

RESUMO

The understanding of immunological interactions among the four dengue virus (DENV) serotypes and their epidemiological implications is often hampered by the lack of individual-level infection history. Using a statistical framework that infers full infection history, we analyze a prospective pediatric cohort in Nicaragua to characterize how infection history modulates the risks of DENV infection and subsequent clinical disease. After controlling for age, one prior infection is associated with 54% lower, while two or more are associated with 91% higher, risk of a new infection, compared to DENV-naive children. Children >8 years old have 55% and 120% higher risks of infection and subsequent disease, respectively, than their younger peers. Among children with ≥1 prior infection, intermediate antibody titers increase, whereas high titers lower, the risk of subsequent infection, compared with undetectable titers. Such complex dependency needs to be considered in the design of dengue vaccines and vaccination strategies.


Assuntos
Anticorpos Antivirais/sangue , Vírus da Dengue/patogenicidade , Dengue/imunologia , Interações entre Hospedeiro e Microrganismos/imunologia , Vacinação/métodos , Adolescente , Fatores Etários , Anticorpos Antivirais/imunologia , Criança , Pré-Escolar , Reações Cruzadas/genética , Reações Cruzadas/imunologia , Dengue/sangue , Dengue/epidemiologia , Dengue/virologia , Vírus da Dengue/genética , Vírus da Dengue/imunologia , Vírus da Dengue/isolamento & purificação , Feminino , Humanos , Masculino , Nicarágua/epidemiologia , Estudos Prospectivos , Fatores de Risco , Sorogrupo , Virulência/genética , Virulência/imunologia
15.
Clin Infect Dis ; 69(12): 2059-2070, 2019 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-30753368

RESUMO

BACKGROUND: Following the conclusion of a human rotavirus vaccine (HRV) cluster-randomized, controlled trial (CRT) in Matlab, Bangladesh, HRV was included in Matlab's routine immunization program. We describe the population-level impact of programmatic rotavirus vaccination in Bangladesh in children <2 years of age. METHODS: Interrupted time series were used to estimate the impact of HRV introduction. We used diarrheal surveillance collected between 2000 and 2014 within the 2 service delivery areas (International Centre for Diarrhoeal Disease Research, Bangladesh [icddr,b] service area [ISA] and government service area [GSA]) of the Matlab Health and Demographic Surveillance System, administered by icddr,b. Age group-specific incidence rates were calculated for both rotavirus-positive (RV+) and rotavirus-negative (RV-) diarrhea diagnoses of any severity presenting to the hospital. We used 2 models to assess the impact within each service area: Model 1 used the pre-vaccine time period in all villages (HRV- and control-only) and Model 2 combined the pre-vaccine time period and the CRT time period, using outcomes from control-only villages. RESULTS: Both models demonstrated a downward trend in RV+ diarrheal incidences in the ISA villages during 3.5 years of routine HRV use, though only Model 2 was statistically significant. Significant impacts of HRV on RV+ diarrhea incidences in GSA villages were not observed in either model. Differences in population-level impacts between the 2 delivery areas may be due to the varied rotavirus vaccine coverage and presentation rates to the hospital. CONCLUSIONS: This study provides initial evidence of the population-level impact of rotavirus vaccines in children <2 years of age in Matlab, Bangladesh. Further studies are needed of the rotavirus vaccine impact after the nationwide introduction in Bangladesh.


Assuntos
Atenção à Saúde , Diarreia/prevenção & controle , Diarreia/virologia , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus/imunologia , Rotavirus/imunologia , Saúde da População Rural , Bangladesh/epidemiologia , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Vigilância em Saúde Pública , Vacinas contra Rotavirus/administração & dosagem , Fatores de Tempo , Cobertura Vacinal
16.
Clin Infect Dis ; 69(10): 1780-1788, 2019 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-30689757

RESUMO

BACKGROUND: The population effects of influenza vaccination in children have not been extensively studied, especially in tropical, developing countries. In rural Senegal, we assessed the total (primary objective) and indirect effectiveness of a trivalent inactivated influenza vaccine (IIV3). METHODS: In this double-blind, cluster-randomized trial, villages were randomly allocated (1:1) for the high-coverage vaccination of children aged 6 months through 10 years with either the 2008-09 northern hemisphere IIV3 or an inactivated polio vaccine (IPV). Vaccinees were monitored for serious adverse events. All village residents, vaccinated and unvaccinated, were monitored for signs and symptoms of influenza illness using weekly home visits and surveillance in designated clinics. The primary outcome was all laboratory-confirmed symptomatic influenza. RESULTS: Between 23 May and 11 July 2009, 20 villages were randomized, and 66.5% of age-eligible children were enrolled (3918 in IIV3 villages and 3848 in IPV villages). Follow-up continued until 28 May 2010. There were 4 unrelated serious adverse events identified. Among vaccinees, the total effectiveness against illness caused by the seasonal influenza virus (presumed to all be drifted A/H3N2, based on antigenic characterization data) circulating at high rates among children was 43.6% (95% confidence interval [CI] 18.6-60.9%). The indirect effectiveness against seasonal A/H3N2 was 15.4% (95% CI -22.0 to 41.3%). The total effectiveness against illness caused by the pandemic influenza virus (A/H1N1pdm09) was -52.1% (95% CI -177.2 to 16.6%). CONCLUSIONS: IIV3 provided statistically significant, moderate protection to children in Senegal against circulating, pre-2010 seasonal influenza strains, but not against A/H1N1pdm09, which was not included in the vaccine. No indirect effects were measured. Further study in low-resource populations is warranted. CLINICAL TRIALS REGISTRATION: NCT00893906.


Assuntos
Vacinas contra Influenza/administração & dosagem , Influenza Humana/prevenção & controle , Vacinação/estatística & dados numéricos , Potência de Vacina , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Método Duplo-Cego , Feminino , Humanos , Lactente , Vírus da Influenza A/genética , Vacinas contra Influenza/imunologia , Influenza Humana/diagnóstico , Influenza Humana/epidemiologia , Masculino , Pessoa de Meia-Idade , População Rural , Senegal/epidemiologia , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/imunologia , Adulto Jovem
17.
PLoS Med ; 14(4): e1002282, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28419095

RESUMO

BACKGROUND: Rotavirus vaccines are now globally recommended by the World Health Organization (WHO), but in early 2009 WHO's Strategic Advisory Group of Experts on Immunization reviewed available data and concluded that there was no evidence for the efficacy or effectiveness of a two-dose schedule of the human rotavirus vaccine (HRV; Rotarix) given early at 6 and 10 wk of age. Additionally, the effectiveness of programmatic rotavirus vaccination, including possible indirect effects, has not been assessed in low-resource populations in Asia. METHODS AND FINDINGS: In Bangladesh, we cluster-randomized (1:1) 142 villages of the Matlab Health and Demographic Surveillance System to include two doses of HRV with the standard infant vaccines at 6 and 10 wk of age or to provide standard infant vaccines without HRV. The study was initiated November 1, 2008, and surveillance was conducted concurrently at Matlab Diarrhoea Hospital and two community treatment centers to identify children less than 2 y of age presenting with acute rotavirus diarrhea (ARD) through March 31, 2011. Laboratory confirmation was made by enzyme immunoassay detection of rotavirus antigen in stool specimens. Overall effectiveness of the HRV vaccination program (primary objective) was measured by comparing the incidence rate of ARD among all children age-eligible for vaccination in villages where HRV was introduced to that among such children in villages where HRV was not introduced. Total effectiveness among vaccinees and indirect effectiveness were also evaluated. In all, 6,527 infants were age-eligible for vaccination in 71 HRV villages, and 5,791 in 71 non-HRV villages. In HRV villages, 4,808 (73.7%) infants received at least one dose of HRV. The incidence rate of ARD was 4.10 cases per 100 person-years in non-HRV villages compared to 2.8 per 100 person-years in HRV villages, indicating an overall effectiveness of 29.0% (95% CI, 11.3% to 43.1%). The total effectiveness of HRV against ARD among vaccinees was 41.4% (95% CI, 23.2% to 55.2%). The point estimate for total effectiveness was higher against ARD during the first year of life than during the second (45.2% versus 28.9%), but estimates for the second year of life lacked precision and did not reach statistical significance. Indirect effects were not detected. To check for bias in presentation to treatment facilities, we evaluated the effectiveness of HRV against acute diarrhea associated with enterotoxigenic Escherichia coli; it was 4.0% (95% CI, -46.5% to 37.1%), indicating that bias likely was not introduced. Thirteen serious adverse events were identified among recipients of HRV, but none were considered related to receipt of study vaccine. The main limitation of this study is that it was an open-label study with an observed-only control group (no placebo). CONCLUSIONS: The two-dose HRV rotavirus vaccination program significantly reduced medically attended ARD in this low-resource population in Asia. Protection among vaccinees was similar to that in other low-resource settings. In low-resource populations with high rotavirus incidence, large-scale vaccination across a wide population may be required to obtain the full benefit of rotavirus vaccination, including indirect effects. TRIAL REGISTRATION: ClinicalTrials.gov NCT00737503.


Assuntos
Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus/administração & dosagem , Vacinação/métodos , Administração Oral , Adolescente , Adulto , Bangladesh , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Masculino , Avaliação de Programas e Projetos de Saúde , Resultado do Tratamento , Vacinas Atenuadas/administração & dosagem , Adulto Jovem
18.
PLoS Negl Trop Dis ; 10(11): e0005105, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27855171

RESUMO

INTRODUCTION: Recurrent cholera outbreaks have been reported in Cameroon since 1971. However, case fatality ratios remain high, and we do not have an optimal understanding of the epidemiology of the disease, due in part to the diversity of Cameroon's climate subzones and a lack of comprehensive data at the health district level. METHODS/FINDINGS: A unique health district level dataset of reported cholera case numbers and related deaths from 2000-2012, obtained from the Ministry of Public Health of Cameroon and World Health Organization (WHO) country office, served as the basis for the analysis. During this time period, 43,474 cholera cases were reported: 1748 were fatal (mean annual case fatality ratio of 7.9%), with an attack rate of 17.9 reported cases per 100,000 inhabitants per year. Outbreaks occurred in three waves during the 13-year time period, with the highest case fatality ratios at the beginning of each wave. Seasonal patterns of illness differed strikingly between climate subzones (Sudano-Sahelian, Tropical Humid, Guinea Equatorial, and Equatorial Monsoon). In the northern Sudano-Sahelian subzone, highest number of cases tended to occur during the rainy season (July-September). The southern Equatorial Monsoon subzone reported cases year-round, with the lowest numbers during peak rainfall (July-September). A spatial clustering analysis identified multiple clusters of high incidence health districts during 2010 and 2011, which were the 2 years with the highest annual attack rates. A spatiotemporal autoregressive Poisson regression model fit to the 2010-2011 data identified significant associations between the risk of transmission and several factors, including the presence of major waterbody or highway, as well as the average daily maximum temperature and the precipitation levels over the preceding two weeks. The direction and/or magnitude of these associations differed between climate subzones, which, in turn, differed from national estimates that ignored subzones differences in climate variables. CONCLUSIONS/SIGNIFICANCE: The epidemiology of cholera in Cameroon differs substantially between climate subzones. Development of an optimal comprehensive country-wide control strategy for cholera requires an understanding of the impact of the natural and built environment on transmission patterns at the local level, particularly in the setting of ongoing climate change.


Assuntos
Cólera/epidemiologia , Clima , Vigilância da População , Análise Espaço-Temporal , Adulto , Camarões/epidemiologia , Cólera/mortalidade , Mudança Climática , Análise por Conglomerados , Surtos de Doenças , Humanos , Incidência , Modelos Estatísticos , Distribuição de Poisson , Chuva , Fatores de Risco , Estações do Ano , Temperatura , Fatores de Tempo
19.
Emerg Infect Dis ; 22(1): 121-3, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26692074

RESUMO

Influenza A(H3N2) strains isolated during 2014-15 in Alachua County, Florida, USA, belonged to hemagglutinin gene clade 3C.2a. High rates of influenza-like illness and confirmed influenza cases in children were associated with a decrease in estimated vaccine effectiveness. Illnesses were milder than in 2013-14; severe cases were concentrated in elderly patients with underlying diseases.


Assuntos
Hemaglutininas/genética , Vírus da Influenza A Subtipo H3N2/genética , Influenza Humana/virologia , Adolescente , Criança , Pré-Escolar , Florida , Testes de Inibição da Hemaglutinação/métodos , Humanos , Lactente , Recém-Nascido , Vírus da Influenza A Subtipo H3N2/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/imunologia
20.
PLoS One ; 10(12): e0143497, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26673631

RESUMO

BACKGROUND: Deficiencies in essential vitamins and minerals-also termed hidden hunger-are pervasive and hold negative consequences for the cognitive and physical development of children. METHODS: This analysis evaluates the change in hidden hunger over time in the form of one composite indicator-the Hidden Hunger Index (HHI)-using an unweighted average of prevalence estimates from the Nutrition Impact Model Study for anemia due to iron deficiency, vitamin A deficiency, and stunting (used as a proxy indicator for zinc deficiency). Net changes from 1995-2011 and population weighted regional means for various time periods are measured. FINDINGS: Globally, hidden hunger improved (-6.7 net change in HHI) from 1995-2011. Africa was the only region to see a deterioration in hidden hunger (+1.9) over the studied time period; East Asia and the Pacific performed exceptionally well (-13.0), while other regions improved only slightly. Improvements in HHI were mostly due to reductions in zinc and vitamin A deficiencies, while anemia due to iron deficiency persisted and even increased. INTERPRETATION: This analysis is critical for informing and tracking the impact of policy and programmatic efforts to reduce micronutrient deficiencies, to advance the global nutrition agenda, and to achieve the Millennium Development Goals (MDGs). However, there remains an unmet need to invest in gathering frequent, nationally representative, high-quality micronutrient data as we renew our efforts to scale up nutrition, and as we enter the post-2015 development agenda. FUNDING: Preparation of this manuscript was funded by Sight and Life. There was no funding involved in the study design, data collection, analysis, or decision to publish.


Assuntos
Deficiência de Vitaminas/epidemiologia , Deficiências Nutricionais/epidemiologia , Minerais , Vigilância em Saúde Pública , Deficiência de Vitaminas/história , Deficiências Nutricionais/história , Saúde Global , História do Século XX , História do Século XXI , Humanos
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