The Ministry of Health in Viet Nam has confirmed three additional cases of human infection with H5N1 avian influenza. The cases concern a 5-year-old boy from the central province of Quang Binh, a 17-year-old girl from the northern province of Nam Dinh, and a 40-year-old woman from the northern province of Quang Ninh. The 17-year-old girl has died.
An earlier case has also been confirmed. These recently confirmed cases bring the total in Viet Nam since mid-December to 28.
WHO is aware of reports of suspected H5 avian influenza infection in five members of a family who are presently hospitalized in the northern port city of Haiphong. These cases, which include the parents and their three young daughters, are undergoing further investigation following initial tests indicating infection with the H5 subtype of avian influenza. Reports indicate outbreaks of avian influenza in poultry in the vicinity. Field investigation of this family cluster is under way.
The current outbreak of human cases in Viet Nam has included several clusters, mostly in family members, of cases closely related in time and place. Thorough investigation of all such clusters is essential to determine possible changes in the behaviour of the virus and thus support assessment of the risk of an influenza pandemic.
There is currently no evidence that the H5N1 virus is spreading easily from person to person. Rapid sharing with WHO of viruses from recent clusters of cases has become increasingly important. Analysis can determine whether any significant changes in the virus have taken place and provide further support for risk assessment.
Several media reports have recently covered rumours of a large outbreak of influenza-like illness in Quang Binh Province. The outbreak is presently under investigation by provincial and central health authorities. Samples have been taken for testing, and WHO is awaiting the results. The number of cases with influenza-like illness appears much smaller than initially reported by the media.
Cambodia
The Ministry of Health in Cambodia has today confirmed the country's second human case of avian influenza.