Health officials warn of rising respiratory infections across Brazil as Fiocruz data shows alert-level conditions in 18 states and the Federal District due to concurrent surges in influenza A and respiratory syncytial virus (VSR).
The latest Fiocruz bulletin, covering March 29 to April 4, found rinovirus responsible for 40.8% of positive respiratory cases, influenza A for 30.7%, and VSR for 19.9%. At least 13 of the affected states show increasing notification trends in the coming weeks.
In Minas Gerais, the Funed foundation reported influenza positivity reached 20% of tests between late March and early April — a shift of four to six weeks earlier than in 2025 — prompting Belo Horizonte and Contagem to declare respiratory health emergencies.
<!– wp:paragraph /> wp:paragraph >At the Hospital Infantil João Paulo II in Belo Horizonte, pediatric urgent care visits rose 65% as influenza A and VSR co-circulation intensified pressure on health services, particularly for children and older adults.
/wp:paragraph –> <!– wp:paragraph /> wp:paragraph >Nationally, VSR caused 37.4% of identified viral SRAG cases in 2025 according to InfoGripe data, with the Rio Grande do Sul state health panel recording 3,621 VSR hospitalizations and 68 deaths that year — a 32% increase from 2024.
/wp:paragraph –> <!– wp:paragraph /> wp:paragraph >In Rio Grande do Sul, infants under one year accounted for 72% of VSR hospitalizations in 2025, totaling 2,589 cases, continuing a steady annual rise from 1,596 in 2023 and 1,977 in 2024.
/wp:paragraph –> <!– wp:paragraph /> wp:paragraph >Pediatric intensive care units in the state routinely fill during winter months due to VSR, which causes bronchiolitis in young children and can rapidly progress to severe respiratory distress requiring ventilatory support.
/wp:paragraph –> <!– wp:paragraph /> wp:paragraph >Anvisa expanded approval this week for the Arexvy vaccine to adults aged 18 and older, previously limited to those 60 and above, citing clinical trials showing non-inferior immune response in younger adults compared to older populations.
/wp:paragraph –> <!– wp:paragraph /> wp:paragraph >The vaccine, produced by GlaxoSmithKline Brasil and registered in 2023, prevents lower respiratory tract disease caused by VSR and is available through private healthcare networks.
/wp:paragraph –>What is driving the early surge in influenza cases in Minas Gerais?
Laboratory surveillance by Funed detected influenza A positivity reaching 20% of tests in late March to early April 2026, occurring four to six weeks earlier than the same threshold reached in May 2025, indicating an accelerated viral circulation pattern.
This follows our earlier report, UK Meningitis Outbreak: Rising Cases & Vaccine Demand | 2024 Updates.
For more on this story, see Vietnam Urges Action Against Rising Meningococcal Cases.
Why are infants and older adults at highest risk from VSR?
<!– wp:paragraph /> wp:paragraph >VSR causes bronchiolitis by inflaming small airways in the lungs; in infants under two and older adults — especially those with weakened immune systems — this can rapidly lead to low oxygen levels, feeding difficulties, and hospitalization for respiratory support.
/wp:paragraph –>How does the co-circulation of influenza A and VSR strain health systems?
<!– wp:paragraph >Simultaneous spread of both viruses increases outpatient and hospital demand, as influenza affects adults and older adults while VSR impacts young children, creating overlapping pressure on clinics and hospitals during peak transmission periods.
