By Dr Ananya Mandal, MD
H1N2 is a subtype of the influenza A virus, which is also referred to as bird flu.
H1N2 is currently poses a tremendous public health concern because it has spread to both human and pig populations. Among humans, only three subtypes of the Influenza A virus are known to exist and these include H1N1, H1N2, and H3N2.
The illness caused by this virus is no more severe than with other flu viruses and it has not been associated with any particular increase in the activity of influenza.
The H1N2 strain was identified between December 1988 and March 1989 in six cities across China. Nineteen H1N2 isolates were identified during this time, but no further spread occurred. During the 2001 to 2002 flu season in the northern hemisphere, A(H1N2) was identified in the United States, Canada, France, Romania, Ireland, Latvia, Oman, India, Malaysia, and Singapore. The earliest reported outbreak occurred in India on May 31st, 2001.
On February 6th, 2002, the first cases of A(H1N2) were reported in the UK, Isreal and Egypt by the World Health Organization (WHO) in Geneva and the Public Health Laboratory Service (PHLS) in the United Kingdom.
Another strain called the 2001-2002 Influenza A(H1N2) Wisconsin seems to have evolved through mutation of the A (H1N1) and A(H3N2) subtypes already circulating. The virus has a similar hemagglutinin protein and neuraminidase protein to those found on the current A(H1N1) virus and H3N2 viruses, respectively. This means the flu vaccine should protect against influenza virus as well as the current A(H1N1), A(H3N2) and influenza B viruses.
Reviewed by Sally Robertson, BSc
Last Updated: Jul 24, 2014