Virus subtype | Clinical presentation | Year | Number of cases | Countries | References |
H3N8 | Mild respiratory illness to fatal pneumonia | 2022 to 2023 | 3 | China | 1-3 |
H5N1 | Asymptomatic, conjunctivitis, respiratory illness, multi-organ failure and death | 1997 to present | >950 | 24 countries | 4 |
H5N2 | Fatal multi-organ failure | 2024 | 1 | Mexico | 5 |
H5N6 | Mild respiratory illness to fatal pneumonia | 2014 to present | >40 | China | 6-11 |
H6N1 | Mild respiratory illness | 2013 | 1 | Taiwan | 12 |
H7N2 | Mild respiratory illness, conjunctivitis | 2002 to 2017 | 8 | United States United Kingdom | 13-17 |
H7N3 | Mild respiratory illness, conjunctivitis | 2003 to 2004 | >55 | Canada United Kingdom | 18-19 |
H7N4 | Severe pneumonia | 2018 | 1 | China | 20 |
H7N7 | Conjunctivitis, mild respiratory illness to fatal pneumonia | 2003 | 89 | Netherlands | 21-23 |
H7N9 | Mild respiratory illness to fatal pneumonia | 2013 to present | >1560 | China Malaysia Canada | 24-36 |
H9N2 | Respiratory illness | 1999 to present | 115 | China Cambodia India Vietnam | 37-40 |
H10N3 | Severe pneumonia | 2022 to present | 4 | China | 41-42 |
H10N5 | Severe respiratory failure | 2024 | 1 | China | 43 |
H10N7 | Mild respiratory illness | 2004 | 2 | Australia | 44-45 |
2010 | 1 | Egypt | |||
H10N8 | Severe pneumonia, multi-organ failure and death | 2013 to 2014 | 3 | China | 46-47 |