Table 1. Infectious diseases in the notifiable diseases surveillance system by severity category included in surveillance for the Tokyo 2020 Olympic and Paralympic Games, 1 July–12 September 2021.

Category	Diseases
I	Crimean-Congo haemorrhagic fever, Ebola haemorrhagic fever, Lassa fever, Marburg disease, plague, smallpox, South American haemorrhagic fever
II	Acute poliomyelitis, avian influenza (H5N1), avian influenza (H7N9), diphtheria, Middle East respiratory syndrome (only if the pathogen is MERS coronavirus), severe acute respiratory syndrome (only if the pathogen is SARS coronavirus)
III	Cholera, Enterohaemorrhagic Escherichia coli infection, paratyphoid fever, shigellosis, typhoid fever
IV	Anthrax, avian influenza (excluding H5N1 or H7N9), B virus disease, botulism, brucellosis, Chikungunya fever, coccidioidomycosis, dengue fever, Eastern equine encephalitis, echinococcosis, epidemic typhus, glanders, haemorrhagic fever with renal syndrome, Hantavirus pulmonary syndrome, Hendra virus infection, hepatitis A, hepatitis E, Japanese encephalitis, Japanese spotted fever, Kyasanur Forest disease, legionellosis, leptospirosis, Lyme disease, lyssavirus infection, malaria, melioidosis, monkeypox, Nipah virus infection, Omsk haemorrhagic fever, psittacosis, Q fever, rabies, relapsing fever, Rift Valley fever, Rocky Mountain spotted fever, severe fever with thrombocytopenia syndrome (only if the pathogen is SFTS virus of the genus Phlebovirus), tick-born encephalitis, Tsutsugamushi disease, tularaemia, Venezuelan equine encephalitis, West Nile fever, Western equine encephalitis, yellow fever, Zika virus infection
V	Invasive meningococcal infection, measles, rubella