New Strain of Avian Flu in China

There is a new strain of avian flu called H7N9 in China. It is generating intense media interest, although so far there only have been 18 cases over the past 6 weeks or so.

Health authorities are concerned for several reasons:

• Although there are only a few cases, the respiratory illness caused by this virus is severe, and 6 of the patients have died
• This is a new bird virus generated in nature by recombinations of known strains
• This strain does not appear to cause any serious illness in chickens or other birds, but it can spread from chickens and other birds to humans to cause serious illness
• The potential for spreading widely is unknown at present

Extensive investigation by Chinese authorities has identified the virus in live poultry markets in Shanghai and Hangzhou. Samples from chickens, but also surprisingly from pigeons and quails, have been positive for this virus. The affected live poultry markets have been shut down and all the birds were culled. Studies are underway to learn more about this virus and how it infected these initial people.

The good news is that over 400 of the personal contacts of the infected people have not become ill — they are being monitored closely. This means that the virus has not been passed from person to person, yet.

It is not clear how widely this virus might spread both inside and outside of China. Until there is more information, travellers in China should avoid all live poultry markets.