What is H3N3?

H3N3 and H1N1 influenza A viruses were isolated from Canadian pigs in 2001 and 2002. These viruses are phylogenetically related to waterfowl viruses and antigenically distinct from reference swine influenza viruses.

Is H3N2 serious?

H3N2 outbreak during the 2017/18 season There were 188 reported pediatric deaths, mostly in unvaccinated children. In comparison, there were 404,646 reported flu-related hospitalizations during the 2019/20 flu season, when influenza B and H1N1 predominated.

What causes H3N2 virus?

The 1968 pandemic was caused by an influenza A (H3N2) virus comprised of two genes from an avian influenza A virus, including a new H3 hemagglutinin, but also contained the N2 neuraminidase from the 1957 H2N2 virus. It was first noted in the United States in September 1968.

What was the H3N2 virus called?

Influenza A H3N2 variant viruses (also known as “H3N2v” viruses) with the matrix (M) gene from the 2009 H1N1 pandemic virus were first detected in people in July 2011. The viruses were first identified in U.S. pigs in 2010. During 2011, 12 human infections with H3N2v were detected.

Is H3N2 worse than H1N1?

“A/H3N2 has become the predominant flu subtype in the United States, and the record over the past 25 years shows that seasons dominated by H3N2 tend to be worse than those dominated by type A/H1N1 or type B.” Many H3N2 viruses making people ill in this 2007–2008 flu season differ from the strains in the vaccine and may …

Is H3N2 the swine flu?

H3N2v is a non-human influenza virus that normally circulates in pigs and that has infected humans. Viruses that normally circulate in pigs are “swine influenza viruses.” When these viruses infect humans, they are termed “variant” viruses.

What does the H and N mean in flu?

Influenza A viruses are divided into subtypes based on two proteins on the surface of the virus: hemagglutinin (H) and neuraminidase (N).