Re-emergence and outbreak dynamics of measles in Bangladesh and trends across South Asia

Measles remains an important vaccine-preventable disease, and recent outbreaks have raised concerns about persistent immunity gaps following disruptions to routine immunization. This study describes the early 2026 measles outbreak in Bangladesh and contextualizes the epidemiological pattern within the broader South Asian region. A retrospective ecological descriptive analysis was conducted using publicly available national and international measles surveillance data. Weekly reported suspected and confirmed cases and deaths in Bangladesh were examined from 15 March to 17 May 2026. Annual reported measles cases in Bangladesh from 2016 to 2026 were also assessed. Annual reported case counts from selected South Asian countries were compared descriptively for 2016–2025. During 15 March–17 May 2026, Bangladesh surveillance reports documented 57,846 suspected cases, 7,767 laboratory-confirmed cases, 384 suspected deaths, and 75 confirmed deaths, with reported transmission in 58 of 64 districts. Dhaka division recorded the highest reported numbers of cases and deaths. Annual reported cases varied substantially from 2016 to 2025, with a non-significant declining linear trend ( P > 0.05). The 2026 data represent only the early outbreak period and were therefore excluded from the regression analysis. Regional comparisons showed substantial year-to-year variation, with higher reported case counts in several years in India, Pakistan, and Afghanistan; these patterns refer to the 2016–2025 comparison period and not specifically to the 2026 Bangladesh outbreak. The findings describe a substantial early-phase measles outbreak in Bangladesh in 2026 following several years of relatively low reported cases. The resurgence may be associated with immunity gaps, immunization disruptions, vaccine supply constraints, and unequal access to vaccination. Strengthening routine and catch-up vaccination, surveillance, and regional information sharing may improve preparedness. Further studies using complete 2026 data, population-adjusted incidence, vaccination coverage, and individual-level information are needed to characterize the outbreak and its determinants.