“Increased efforts to educate the public about avian influenza will be crucial in the detection and control of any future outbreak,” said Jim Tulloch, country representative of the World Health Organization (WHO), which is working with the Cambodian Health Ministry on the surveillance in Kampot province.

“There is no way to accurately predict what lies ahead, but by putting emphasis on surveillance, WHO and the Cambodian Government are investing in the best response to any potential outbreak: preparedness,” he added.

WHO has repeatedly warned that in a worst-case scenario bird flu could give rise to a new human virus with pandemic potential. The so-called Spanish flu pandemic of 1918-20, which was not related to bird flu, is estimated to have killed 20 million people worldwide.

The H5N1 virus last year sickened some 50 people, over three dozen of them fatally, and resulted in the deaths or culling of more than 100 million birds in nearly a dozen Asian countries.

The Health Ministry confirmed over the weekend that a 25-year-old woman from Kampot province who died in Viet Nam on 30 January was positive for the virus. The woman’s 14-year-old brother died after experiencing respiratory symptoms and is suspected to have been infected but no diagnostic samples were collected before his cremation. All of the case’s close contacts will remain under observation until 14 February when two incubation periods will have passed.

WHO has warned that cooler winter temperatures and increased poultry marketing, transportation and consumption linked to Lunar New Year celebrations this month could increase the risk of further human cases.