How did the 1957 flu pandemic end?
After 10 years of evolution, the 1957 flu virus disappeared, having been replaced through antigenic shift by a new influenza A subtype, H3N2, which gave rise to the 1968 flu pandemic.
What was the 1957 flu pandemic called?
In February 1957, a new influenza A (H2N2) virus emerged in East Asia, triggering a pandemic (“Asian Flu”).
Was there a pandemic in 1992?
From October 1991 through February 1992, when influenza viruses circulated widely in the Northern Hemisphere, epidemic levels of activity were most commonly associated with the H3N2 subtype of influenza A (1).
How long did the 1968 flu pandemic last?
1968 flu pandemic, also called Hong Kong flu pandemic of 1968 or Hong Kong flu of 1968, global outbreak of influenza that originated in China in July 1968 and lasted until 1969–70.
What was the most severe flu outbreak of the 20th century?
The 1918 influenza pandemic was the most severe pandemic in recent history. It was caused by an H1N1 virus with genes of avian origin. Although there is not universal consensus regarding where the virus originated, it spread worldwide during 1918-1919.
How is H7N9 transmitted?
A(H7N9) virus does not transmit easily between humans, and person-to-person spread has been limited to 2 or possibly 3 generations of transmission (2,4). Assuming transmission remains unchanged, geographic spread probably will occur through travel of infected humans or infected poultry.
Is there a vaccine for H7N9?
Currently, there is no vaccine for H7N9 infection. Scientists have taken early steps to identify a strain of the virus that could be used to make a vaccine if it is needed. The seasonal flu vaccine will not protect against H7N9. Seasonal flu vaccines protect against seasonal influenza viruses.
Where did the Spanish flu come from China?
He found archival evidence that a respiratory illness that struck northern China (where the laborers came from) in November 1917 was identified a year later by Chinese health officials as identical to the Spanish flu. However, no tissue samples have survived for modern comparison.