WHO: H1N1 still a global threat

(The Philippine Star) Updated November 25, 2009 12:00 AM

MANILA, Philippines - The World Health Organization (WHO) warned yesterday that the Avian Influenza or A-H5N1 remains a threat to humans, with newly confirmed cases reported in Egypt, Indonesia, Thailand and Vietnam.

In a statement, WHO said the presence of the A-H5N1 in poultries in these countries poses a health risk in two ways.

First, those in direct contact with birds – usually rural folk and farm workers – are in danger of contracting the virus. Second, the virus can undergo a process of “re-assortment” with another influenza viruses, thus producing a new strain.

WHO said the “most obvious risk is of H5N1 combining with the pandemic influenza A(H1N1) 2009 virus, producing a flu virus that is as deadly as the former and as contagious as the latter.”

“We don’t know if this is possible, but we are certainly aware of the risk. We are on alert for this development,” said Dr. Shin Young-soo, WHO Regional Director for the Western Pacific.

Re-assortment takes place when the genes of two or more types of influenza virus mix in a host animal – often a pig, duck or chicken – and form an entirely new strain of the virus.

Last April, after the re-assortment of avian, swine and human strains of influenza in pigs in Mexico, a novel influenza virus —the pandemic influenza A(H1N1) virus —emerged in humans. The virus spread quickly across the world.

“Influenza viruses are unpredictable. In areas where A(H1N1) is endemic, we and our partners and national governments are working to build surveillance systems to identify changes in the behavior of the virus. We are also focusing on early-response capacity to reduce the potential threats to human health,” Shin added. —Sheila Crisostomo