Summary of global surveillance data of infectious diseases in May 2026

In May 2026, a total of 71 infectious diseases were reported globally, affecting 124 countries and territories. Except for influenza, the top five infectious diseases affecting greatest number of countries and territories were mpox (71), Coronavirus disease 2019 (COVID-19) (64), dengue fever (32), measles (30) and chikungunya virus disease (16). The top five infectious diseases with highest case fatality rates were yellow fever (34.74%), hantavirus infection (32.71%), Lassa fever (25.09%), Ebola disease (19.86%) and meningitis (4.87%). The prevalent infectious diseases in Africa were Ebola disease, cholera, yellow fever, Lassa fever, poliomyelitis, mpox and measles, the prevalent infectious diseases in Asia were cholera, poliomyelitis, dengue fever, mpox and measles, the prevalent infectious diseases in America were yellow fever, COVID-19, dengue fever, chikungunya virus disease, mpox, hantavirus infection and measles, the prevalent infectious diseases in Europe were COVID-19, mpox and measles.