Influenza A virus subtype H2N2

Russian flu

Some believe that the 1889–1890 Russian flu was caused by the influenzavirus A virus subtype H2N2, but the evidence is not conclusive. It is the earliest flu pandemic for which detailed records are available. More recently, there are speculations that it might have been caused by one of the coronaviruses first discovered in the 1960s.

Asian flu

Main article: 1957–1958 influenza pandemic

The "Asian Flu" was a category 2 flu pandemic outbreak of influenzavirus A that first appeared in Guizhou, China in early 1957 and lasted until 1958. The first cases were reported in Singapore in February 1957. In February 1957, a new influenza A (H2N2) virus emerged in East Asia, triggering a pandemic (“Asian Flu”). This H2N2 virus was composed of three different genes from an H2N2 virus that originated from an avian influenza A virus, including the H2 hemagglutinin and the N2 neuraminidase genes. It was first reported in Singapore in February 1957, Hong Kong in April 1957, and in coastal cities in the United States in summer 1957. Some authors believe it originated from mutation in wild ducks combining with a pre-existing human strain. Other authors are less certain. It reached Hong Kong by April, and US by June. Estimates of US and worldwide deaths caused by this pandemic varies widely depending on source; ranging from approximately 69,800 to 116,000 in the United States, and worldwide from 1 million to 4 million, with the World Health Organization (WHO) settling on "about 2 million," with an overall mortality rate of 0.6%.

The Asian Flu strain later evolved via antigenic shift into H3N2 which caused a milder pandemic from 1968 to 1969.

Both the H2N2 and H3N2 pandemic strains contained avian influenza virus RNA segments.

Test kits

From October 2004 to February 2005, approximately 3,700 test kits of the 1957 H2N2 virus were accidentally spread around the world from the College of American Pathologists (CAP). CAP assists laboratories in accuracy by providing unidentified samples of viruses; private contractor Meridian Bioscience in Cincinnati, U.S., chose the 1957 strain instead of one of the less deadly avian influenza virus subtypes.

References

References

1. Hilleman, Maurice R.. (2002). "Realities and enigmas of human viral influenza: pathogenesis, epidemiology and control". Vaccine.
2. (April 2, 1998). "The Influenza H5N1 Report".
3. Alexis Madrigal. (April 26, 2010). "1889 Pandemic Didn't Need Planes to Circle Globe in 4 Months". Wired Science.
4. "Encarta on influenza".
5. Anthony King: [https://www.newscientist.com/article/mg24632800-700-what-four-coronaviruses-from-history-can-tell-us-about-covid-19/ What four coronaviruses from history can tell us about covid-19], on: New Scientist, 29 April 2020
6. (2006). "A slippery disease: a microbiologist's view". BMJ.
7. Green, Jeffrey. (2006). "The Bird Flu Pandemic". St. Martin's Griffin.
8. Belshe, Robert B.. (2005-11-24). "The Origins of Pandemic Influenza — Lessons from the 1918 Virus". New England Journal of Medicine.
9. (22 January 2019). "1957-1958 Pandemic (H2N2 virus)". U.S. Department of Health & Human Services.
10. (26 March 2020). "The coronavirus may be deadlier than the 1918 flu: Here's how it stacks up to other pandemics". f NBCUniversal.
11. Starling, Arthur E.. (2006). "Plague, SARS, and the story of medicine in Hong Kong". Hong Kong University Press.
12. [http://www.influenzareport.com/ir/ai.htm Chapter Two : Avian Influenza by Timm C. Harder and Ortrud Werner] {{Webarchive. link. (2017-08-09 from free on-line Book called ''Influenza Report 2006'' which is a medical textbook that provides a comprehensive overview of epidemic and pandemic influenza.)
13. Roos, Robert. (April 13, 2005). "Vendor thought H2N2 virus was safe, officials say".