H1N1

American  

Pathology.

1. a subtype of the type A influenza virus, with strains that give rise to seasonal epidemics, or sometimes pandemics, including a strain with swine, avian, and human genes responsible for swine flu.

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Etymology

Origin of H1N1

First recorded in 1970–75; abbreviation of h(aemagglutinin type)1 and n(euraminidase type) 1

Example Sentences

See Examples For:

H1N1

During the 2009 H1N1 “swine” flu pandemic, getting newly formulated shots “took a lot longer than we hoped,” Pan said.

From Los Angeles Times ● Aug. 14, 2026

He advised each of the last seven U.S. presidents on new viral epidemics faced by the world, including multiple recurrences of Ebola, HIV/AIDS, Sars-CoV-1, H1N1 Influenza, Zika and then Sars-CoV-2, which causes Covid-19.

From The Wall Street Journal ● Aug. 7, 2026

The 2009 H1N1 flu pandemic led to 274,304 hospitalizations and 12,469 deaths.

From Science Daily ● Feb. 7, 2026

There are also signs a different strain of flu - H1N1 - is picking up in Europe and may lead to an increase in cases here too.

From BBC ● Dec. 19, 2025

Right now the U.S. poultry industry is under tremendous threat from H1N1 bird flu.

From Salon ● Jan. 24, 2025