Feb 23, 2010 (CIDRAP News) – Vietnam's health ministry announced the country's first H5N1 avian influenza case of the year, a 3-year-old girl who is recovering in the hospital, according to media reports.
The report of a new human case follow several recent outbreaks in poultry and as new research reveals live-bird trading patterns in Vietnam that could contribute to the spread of the H5N1 virus among poultry flocks. The study, by an international group of researchers, appeared yesterday in an early online edition of BMC Veterinary Research.
The girl is from Khanh Hoa province in central Vietnam, Thanh Nien news reported today. She came down with flu symptoms on Jan 27 and was hospitalized the next day, the news report said. Her infection was confirmed on Feb 12. If the World Health Organization (WHO) confirms the girl's illness, she will be listed as the country's 113th case, of which 57 have been fatal.
Vietnam last reported a human H5N1 case in December, a man from Dien Bien province who died in November.
Meanwhile, the virus recently struck two duck flocks, one in the northern Nam Dinh province and the other in the southern province of Soc Trang, Thanh Nien news, citing local news sources, reported on Feb 19. The outbreak in Soc Trang hit a farm, and the one in Nam Dinh involved a family's flock.
Investigators didn't find any signs of sick poultry at the girl's home or commune, but about a month ago they learned that ostriches at a farm about a kilometer from her home had died from undetermined illness, the new report said.
Vietnam has recently reported several other H5N1 outbreaks. On Feb 13 the country's veterinary authorities filed a report with the World Organization for Animal Health (OIE) listing 13 H5N1 avian influenza outbreaks in poultry since Jan 20. Outbreaks occurred in seven different provinces. The report said factors that probably contributed to the spread of the virus included the introduction of new animals, illegal poultry movement, and fomites.
In yesterday's BMC Veterinary Research report, investigators tracked connections among farms, poultry traders, and live bird markets in northern Vietnam from 2003 to 2006. Though scientists know that live bird markets in some countries contribute to the spread of the H5N1 virus, few researchers have documented trading patterns to assess which practices are linked to outbreaks.
They found that live poultry traders who have been trading for less than a year and operate at retail markets are more likely to get their birds from communes that have a history of H5N1 outbreaks. Findings suggested that live poultry traders who had been in business for more than a year and who dealt primarily with wholesale dealers were less likely to obtain their birds from infected farms.
The group speculated that those who are relatively new to the poultry trade are more likely to operate in areas that have a history of H5N1 outbreaks, perhaps because of their inexperience. They also wrote that experienced traders might avoid outbreak areas.
The authors concluded that identifying the patterns could lead to practices aimed at new bird traders, such as distributing current information on the geographic location of H5N1 outbreaks and developing more biosecure trading practices such as cleaning and disinfecting poultry crates. They also suggested implementing data recording at live bird markets for all incoming and outgoing traders.
Feb 22 BMC Veterinary Research abstract