Dec 28, 2007 (CIDRAP News) – The World Health Organization (WHO) today confirmed three human cases of H5N1 avian influenza in Vietnam and Egypt, one of which was fatal, raising the global H5N1 count to 346 cases with 213 deaths.
In Vietnam, a 4-year-old boy from the northern province of Son La died of an H5N1 infection Dec 16, the WHO said. He fell ill Dec 7 and was hospitalized on the 11th. His case was first reported by news services on Dec 26.
The boy's source of exposure is under investigation, the WHO said. His close contacts are being monitored, and all remain healthy so far, the agency reported.
Two women in Egypt are being treated for H5N1 disease, the WHO said. One is a 50-year-old from Domiatt governorate who was hospitalized Dec 24 and is in critical condition. The other is a 22-year-old chicken seller from Menofia governorate; she was hospitalized Dec 26 and is in intensive care but recovering, the WHO reported.
"Both women had contact with sick and dead poultry prior to illness onset," the agency said. News services first reported their cases yesterday.
Vietnam has had 101 confirmed H5N1 cases with 47 deaths, while Egypt has had 41 confirmed cases, 16 of them fatal.
More details on Pakistan cases
Meanwhile, a Canadian Press (CP) story published yesterday provided more details about the recent cluster of suspected H5N1 patients in Pakistan, saying that confirmatory testing by the WHO yielded negative findings in several of the cases, along with the single case confirmation announced yesterday.
The agency said yesterday that its reference laboratories had confirmed H5N1 in one man in a cluster of several people who had tested positive in Pakistan. He was one of several brothers who had fallen ill after caring for another brother, a veterinarian who had gotten sick after culling infected poultry. Because the man with the confirmed case had not been involved in culling, the confirmation supported the WHO's previously stated view that limited person-to-person transmission probably occurred in the family.
The CP report, based mainly on an interview with the WHO's Dr. Frederick Hayden, said testing by Pakistan's National Institute of Health had identified nine possible H5N1 cases. The case-patients included five people in one family, a female doctor who had treated the family, and three poultry cullers unrelated to the family. Another brother in the affected family also had a suspicious illness but died without being tested and therefore was not counted as a possible case.
The story said tests by the WHO's collaborating lab in London and by US Navy Medical Research Unit 3 (NAMRU-3) in Cairo found no H5N1 virus in six of the nine people: the doctor, the three poultry cullers, a brother in the affected family who had never been sick, and a cousin who lived near the affected family and had been sick. One of the three cullers tested positive for a human flu virus, H1N1.
Blood test results awaited
But Hayden said other members of the family besides the 25-year-old man probably had the H5N1 virus and that blood serum tests for antibodies to the virus were being done to clarify the situation, according to the story. He said the negative test results might have been caused by deterioration of the patients' samples due to repeated freezing and thawing. The results also might have been affected by the timing of the sample-taking and possible use of antiviral drugs by the patients, he said.
"Until the follow-up serology (blood testing) is done, we can't be strong in saying that H5 has been ruled out in any of these people," Hayden told CP.
The story did not specify the WHO confirmatory test results for the veterinarian or another brother who had been hospitalized with H5N1-like illness but survived.
The WHO said yesterday that all other members of the affected family, other close contacts of the suspected case-patients, and involved healthcare workers remained healthy and had been released from close medical observation.
WHO statement on Egyptian cases
WHO statement on case in Vietnam