Francisco José de Paula Júnior

Influenza A(H3N2) viruses show continuous antigenic and genetic evolution, requiring sustained molecular surveillance to understand their circulation and geographic spread. This study investigated the epidemiological, evolutionary, and phylogeographic dynamics of A(H3N2) viruses circulating in Brazil between 2011 and 2019. Epidemiological surveillance data from Northern and Northeastern Brazil were analyzed together with hemagglutinin (HA) gene sequences generated in this study and sequences retrieved from GISAID EpiFlu database. Phylogenetic and Bayesian phylogeographic analyses were performed to characterize genetic diversity and viral dispersal. Among 23,278 respiratory samples, 1,003 (4.31%) were positive for A(H3N2), with seasonal peaks occurring mainly between epidemiological weeks 13 and 16. Phylogenetic analyses revealed successive lineage replacement, with predominance of 3C.2a-derived clades after 2015. Phylogeographic reconstruction identified multiple international introductions into Brazil and extensive viral movement among Brazilian regions, with Southeastern Brazil acting as the main hub of national connectivity. Northern and Northeastern Brazil participated predominantly as recipient regions while also contributing to onward viral dissemination. These findings highlight the interconnected nature of A(H3N2) circulation in Brazil and reinforce the importance of integrating genomic and epidemiological surveillance to understand influenza dynamics.

Background: Respiratory syncytial virus, a major cause of respiratory infections and hospitalizations in young children, especially bronchiolitis, is an important burden to the health system in Brazil. This study evaluated the trends, seasonality, and economic impact of hospitalizations associated with respiratory syncytial virus in Brazilian children. Methods: This study analyzed hospitalizations for acute bronchitis and bronchiolitis (International Code of Diseases-10 J20-J21) in Brazilian children <5 years of age from January 2014 and March 2025 using data from the Brazil’s Unified Health System. Annual trends were assessed with linear regression, while time series decomposition evaluated seasonality. Direct medical costs were adjusted for inflation and converted to international dollars (Int$). Pearson’s correlation coefficient was employed to analyze associations between length of stay and hospitalization cost. Results: A total of 727,808 hospitalizations were recorded, with 86.8% occurring in children under 5 years old. Hospitalizations increased by 307.8%, with marked declines in 2020 during the coronavirus disease-2019 pandemic and consistent seasonal peaks between March-June. Direct medical costs totaled Int$ 166.8 million, with 55.5% of expenditures after 2020. The mean cost per hospitalization increased by Int$ 21.48 between 2014-2024 (Int$ 118.16-139.64). Length of stay correlated moderately with cost (r = 0.55), particularly strongly in southeastern and southern Brazil. Conclusions: Our findings revealed distinct seasonal and regional patterns in hospitalizations and a post-pandemic increase in costs. The association between prolonged hospitalization and higher expenditures underscores the need for targeted, region-specific preventive strategies and timely clinical interventions, to reduce the growing economic burden on the system.

Objective: To estimate the incidence of influenza-associated hospitalizations and deaths in Brazil from 2010 to 2016. Method: Records of hospital discharges and deaths (mortality system) were used by ICD codes J09-J18, data from laboratory influenza surveillance, and census population projections adjusted by the percentage of those using public health services. Meta-analysis was performed to determine the incidences of hospitalizations and deaths by age group in the five geographic regions of Brazil. Results: The estimates were 645,661 hospitalizations and 160,089 deaths from influenza from 2010 to 2016. The highest incidences of hospitalization occurred in older adults with ≥65 years (258.6/100.000) and children <5 years old (180.1/100,000), while deaths stood out among individuals aged ≥65 (142.9/100,000) and aged 50 to 64 years (22.1/100,000). Regional differences were found, with higher incidences predominantly in the Midwest, Southeast, and South regions. Conclusion: The burden of influenza in Brazil is of concern, with a high number of hospitalizations and deaths from the disease. Regional and age group differences provide evidence to support vaccination policy and the improvement of the influenza surveillance system. Key Words: Human Influenza, Incidence, Mortality, Hospitalization, Meta-analysis

We describe the epidemiological characteristics, pattern of circulation, and geographical distribution of influenza B viruses and its lineages using data from the Global Influenza B Study. We included over 1.8 million influenza cases occurred in thirty-one countries during 2000–2018. We calculated the proportion of cases caused by influenza B and its lineages; determined the timing of influenza A and B epidemics; compared the age distribution of B/Victoria and B/Yamagata cases; and evaluated the frequency of lineage-level mismatch for the trivalent vaccine. The median proportion of influenza cases caused by influenza B virus was 23.4%, with a tendency (borderline statistical significance, p = 0.060) to be higher in tropical vs. temperate countries. Influenza B was the dominant virus type in about one every seven seasons. In temperate countries, influenza B epidemics occurred on average three weeks later than influenza A epidemics; no consistent pattern emerged in the tropics. The two B lineages caused a comparable proportion of influenza B cases globally, however the B/Yamagata was more frequent in temperate countries, and the B/Victoria in the tropics (p = 0.048). B/Yamagata patients were significantly older than B/Victoria patients in almost all countries. A lineage-level vaccine mismatch was observed in over 40% of seasons in temperate countries and in 30% of seasons in the tropics. The type B virus caused a substantial proportion of influenza infections globally in the 21^st century, and its two virus lineages differed in terms of age and geographical distribution of patients. These findings will help inform health policy decisions aiming to reduce disease burden associated with seasonal influenza.

Despite having influenza vaccination policies and programs, countries in the Americas underutilize seasonal influenza vaccine, in part because of insufficient evidence about severe influenza burden. We aimed to estimate the annual burden of influenza-associated respiratory hospitalizations in the Americas. Thirty-five countries in the Americas with national influenza surveillance were invited to provide monthly laboratory data and hospital discharges for respiratory illness (International Classification of Diseases 10^th edition J codes 0–99) during 2010–2015. In three age-strata (<5, 5–64, and ≥65 years), we estimated the influenza-associated hospitalizations rate by multiplying the monthly number of respiratory hospitalizations by the monthly proportion of influenza-positive samples and dividing by the census population. We used random effects meta-analyses to pool age-group specific rates and extrapolated to countries that did not contribute data, using pooled rates stratified by age group and country characteristics found to be associated with rates. Sixteen of 35 countries (46%) contributed primary data to the analyses, representing 79% of the America’s population. The average pooled rate of influenza-associated respiratory hospitalization was 90/100,000 population (95% confidence interval 61–132) among children aged <5 years, 21/100,000 population (13–32) among persons aged 5–64 years, and 141/100,000 population (95–211) among persons aged ≥65 years. We estimated the average annual number of influenza-associated respiratory hospitalizations in the Americas to be 772,000 (95% credible interval 716,000–829,000). Influenza-associated respiratory hospitalizations impose a heavy burden on health systems in the Americas. Countries in the Americas should use this information to justify investments in seasonal influenza vaccination—especially among young children and the elderly.

The system is useful in meeting the goals of SSILI; however, there are some recommendations for adjustments and for encouraging the adherence by the states that do not use the system yet.

Resumo OBJETIVO: descrever a estratégia de vigilância ativa em tempo real e o perfil dos atendimentos de saúde realizados no período da 20ª Copa do Mundo da FIFA Brasil 2014 (CMFB), na cidade-sede de Fortaleza, Ceará, Brasil. MÉTODO: estudo descritivo com dados das fichas de atendimento relacionados à Copa, entre 8/6 e 13/7/2014, nas unidades de saúde pré-selecionadas. RESULTADOS: foram 2.570 atendimentos relacionados à CMFB, 56% de indivíduos do sexo masculino, 35% de 20 a 29 anos de idade, 68% foram atendimentos clínicos, 64% de torcedores/espectadores; 94% dos atendidos foram liberados, 3% removidos, 3% internados e 0,2% idos a óbito; os postos médicos avançados responderam por 79% dos atendimentos, principalmente nos dias de jogos. CONCLUSÃO: não foram identificados eventos de Saúde Pública de grande relevância; a estratégia de vigilância ativa possibilitou monitorar a situação de saúde dos envolvidos no evento

To report the experience of investigating the outbreak of acute diarrhoea (AD) at the XII Indigenous Games in Cuiabá, Mato Grosso, Brazil, 2013. data were collected from the Advanced Medical Post's service records of the AD cases, which were defined as 'individual Games participant referring episode of diarrhoea and/or vomiting'; AD attack rates, relative frequencies and measures of the central tendency of sociodemographic and clinical variables, sanitary inspections and results of bromatological samples were calculated. 384 (37%) cases met the definition of AD; the epidemic peaks of the outbreak occurred on the 4th and 7th day of the event and the disease attack rate was 33.5%; sanitary inspection showed evidence of food contamination by coagulase-negative Staphylococci, Bacillus cereus and heat resistant coliforms. there an outbreak of AD caused by food contamination.

Resumo Este trabalho teve como objetivo descrever os acidentes de trânsito ocorridos na cidade de Fortaleza, capital do Ceará, no ano de 2006. Foi realizado um estudo descritivo, transversal, a partir de dados do Sistema de Informação de Acidentes de Trânsito de Fortaleza, que agrega todas as informações pertinentes aos acidentes de trânsito ocorridos na capital cearense, além de informações do Sistema de Informações Hospitalares. Esses dados foram analisados utilizando o software EPI INFO®. Em 2006, foram registrados 23.443 acidentes de trânsito. Desses, houve uma proporção de 2:1, entre homens e mulheres e os óbitos ocorreram principalmente na faixa etária de 30 a 59 anos, liderados por pedestres 141 (41,34%) e motociclistas com 76 (22,28%). Entre os tipos de acidentes 14.267 (60,85%) registraram-se colisões, tendo o mês de dezembro e o intervalo de 18 às 20 horas apresentado o maior número de registros. Em relação aos ferimentos, os motociclistas foram os mais lesionados, atingindo 5.634 (40,57%) pessoas. Parte significativa dos acidentes e óbitos envolveu adolescentes e adultos jovens, resultando em 341 (0,71%) vitimas que evoluíram para óbito. É fundamental estimular políticas públicas para melhoria nas condições de trânsito e um maior investimento para os sistemas que coletam informações sobre os acidentes.