UN warns of risk of bird flu evolving into human pandemic after three new deaths
“The confirmation of these latest human cases underscores the risk of virus transmission to humans from infected poultry,” the Geneva-based World Health Organization (WHO) said of the new cases, which follow an outbreak earlier this year that infected 34 people, 23 of them fatally, in South and East Asia and resulted in the deaths or culling of more than 100 million birds.
“This risk will continue as long as outbreaks are occurring in poultry. Of greatest concern is the risk that continuing transmission of the virus to humans will give avian and influenza viruses an opportunity to exchange genes, potentially giving rise to a new virus with pandemic potential,” it added.
Initial tests identified the latest virus as belonging to the H5 subtype and further testing is needed to determine whether it belongs to the same highly pathogenic avian influenza (H5N1) strain that caused the earlier outbreak, WHO said. To date, H5N1 is the only strain of the H5 subtype known to jump directly from infected poultry to humans.
Staff from the WHO country office in Viet Nam is meeting with the Ministry of Health to gather further details and work out plans to address the situation. The Government has announced an initial series of measures aimed at controlling the disease in poultry and preventing further cases in humans.
WHO regards it as particularly important that viruses from these cases be made available for further analysis by laboratories in the WHO Global Influenza Surveillance Network to determine whether it has mutated and thus yield valuable information about the further evolution of the outbreak, risks to humans, and best preventive measures.
Studies of the virus are also important in the further development, presently under way, of an effective human vaccine.
The latest outbreak among poultry has been reported from China, Indonesia and Thailand. The earlier cases affected Cambodia, China, Indonesia, Japan, the Republic of Korea, Laos, Thailand and Viet Nam, and poultry was also culled in Pakistan.