WHO says pandemic risk unchanged; fatal H5N1 case reported in Vietnam

Jun 30, 2005 (CIDRAP News) – The World Health Organization (WHO) said today that the threat of an influenza pandemic remains the same, despite recent findings that the H5N1 virus has not grown more infectious for humans.

Meanwhile, another fatal human case of H5N1 flu has been reported in Vietnam. A 73-year-old man died of the illness in Hanoi on Jun 28, according to news stories citing Vietnamese newspaper and television reports. The man is the 19th Vietnamese to die of avian flu since December 2004 and the 39th since late 2003, according to the reports.

The WHO statement came after an international team of experts completed a week of studies in Vietnam and submitted preliminary findings to the Vietnamese government yesterday. An Agence France-Presse (AFP) report yesterday said the experts concluded that the virus had not improved its ability to spread among humans. The report quoted Hans Troedsson, the WHO's Vietnam representative, as calling the pandemic threat "not as imminent as we initially might have suspected."

In its statement today, the WHO affirmed that the virus does not seem to be growing more dangerous, but also moved to head off complacency: "The team found no laboratory evidence suggesting that human infections are occurring with greater frequency or that the virus is spreading readily among humans. The current level of pandemic alert, which has been in effect since January 2004, remains unchanged.

"Some reports now circulating suggest that WHO has downgraded its assessment of the pandemic threat. These reports are unfounded."

The statement goes on to explain that the expert panel's mission was to investigate concerns, first raised at a Manila meeting early in May, that the H5N1 virus might be improving its ability to spread from person to person. Those concerns were based on the observation of a growing number of case clusters and milder cases across a wider age range, mainly in northern Vietnam.

"More recently," the statement continues, "testing of clinical specimens by international experts working in Viet Nam provided further suggestive evidence of more widespread infection with the virus, raising the possibility of community-acquired infection. These findings have not been confirmed by the present investigative team."

Because detecting H5N1 in clinical samples is difficult, the team took sophisticated lab equipment and WHO-approved reagents and primers with them to Vietnam, the agency said. "While these first results are reassuring, further retesting of clinical specimens will continue over the next few weeks to provide the most reliable possible foundation for risk assessment," the statement concludes.

The latest fatal human case of H5N1 flu in Vietnam was reported yesterday by AFP, citing a state-controlled television report. Today the Chinese news service Xinhua reported the case, attributing the information to the Vietnamese newspaper Youth.

The man was admitted to Hanoi's Institute of Tropical Diseases Jun 23 and died Jun 28, Xinhua reported. The story said the institute was also treating five other avian flu patients, but gave no details on them. The AFP story said two other patients had tested positive and were hospitalized, but it didn't give any details either.

In related developments, Vietnamese officials voiced dissatisfaction with avian flu control efforts and announced plans to begin a poultry vaccination program in August, according to reports published today.

The Vietnam News Service (VNS) said the Ministry of Agriculture will begin vaccinating poultry in the northern province of Nam Dinh and the southern province of Tien Giang in early August.

Plans call for expanding the vaccination effort nationwide in October, according to an AFP report quoting an agriculture ministry official. Vaccines will be imported from China and the Netherlands.

Bui Quang Anh, director of the country's Animal Health Department, complained that Hanoi and many other localities "had failed to implement government plans to closely control poultry breeding, selling and slaughtering areas," according to VNS.

Further, Bui said, "Only about 10 percent of H5N1-positive birds have been destroyed, because breeders are unhappy with the government's subsidy programs." The government decided this week to raise its subsidy to farmers to the equivalent of $1.15 per culled bird, AFP reported.

Besides the vaccination campaign, avian flu control efforts include banning poultry raising in central areas of cities and towns and building "concentrated fowl slaughterhouses and distribution networks," the Xinhua report said.

See also:

Jun 30 WHO statement
http://www.who.int/csr/don/2005_06_30/en/index.html

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