Your browser is no longer supported

For the best possible experience using our website we recommend you upgrade to a newer version or another browser.

Your browser appears to have cookies disabled. For the best experience of this website, please enable cookies in your browser

We'll assume we have your consent to use cookies, for example so you won't need to log in each time you visit our site.
Learn more

Flu outbreaks usually originate in Asia

  • Comment

Scientists have discovered that influenza epidemics from the most common subtype come from viruses originating in East and Southeast Asia.

Cambridge University researchers examined 13,000 samples of influenza A (H3N2) virus collected through the World Health Organization Global Influenza Surveillance Network from 2002-2007.

New strains of the virus emerged in East and Southeast Asia, travelled across to Europe and North America six to nine months later, and then on to South America, says the paper in Science Journal. They did not usually return to their ‘countries of origin’.

Flu viruses tend to cause disease outbreaks in the winter months of temperate countries and in the rainy seasons of tropical ones. As the rainy season occurs at different times across East and Southeast Asia, this, and the wintertime epidemics in temperate areas, allows the virus to circulate all year round in this region.

This enables these strains to be the source of epidemics that occur in other parts of the planet, the investigators found.

  • Comment

Have your say

You must sign in to make a comment

Please remember that the submission of any material is governed by our Terms and Conditions and by submitting material you confirm your agreement to these Terms and Conditions. Links may be included in your comments but HTML is not permitted.