April 15th, 2006 00:29 EST
Mammals Not Considered Bird Flu Carriers
Birds remain primary transmitters; additional human cases in Egypt reported
Washington – Domestic cats are not playing a significant role in the transmission of avian influenza, even though several feline cases of the disease have been reported.
The Food and Agriculture Organization of the United Nations (FAO) and the World Organisation for Animal Health (OIE) reported April 13 that epidemiological data show that domestic and wild birds remain the primary transmitters of the bird flu. As many as 50 nondomestic bird species are vulnerable to infection, according to the statement, but “aquatic birds play a major role.”
In February, German health officials confirmed the H5N1 strain of avian flu as the cause of a cat’s death on the Baltic Sea island of Ruegen. Authorities theorized that the cat had contracted the disease by eating an infected bird, thus suggesting that the virus might be introduced into the food chain, creating vulnerabilities for any variety of predatory animals, or humans in contact with them.
Earlier cases had introduced the possibility. Captive tigers at a Thailand zoo died in 2004, after being infected with H5N1 by sick birds that had been fed to the big cats. Cases of infected civet cats had been detected elsewhere in Asia.
Infection of the domestic cat in Germany drew a swift response from the European Commission in early March.
“No H5N1 infection has ever occurred in humans due to animals other than domestic poultry,” according to a European Commission statement of March 1. “Current knowledge suggests that the disease in carnivores such as cats is a ‘cul de sac’ [dead end] of the infection that has not lead to an increase in the risk posed by this virus for animal or public health.”
However, the European Commission did recommend that pet owners take a few precautions – prevent contact between wild birds and cats and dogs, and seek veterinary attention for any sick pet.
EGYPTIAN CASES INCREASE
Egypt’s Ministry of Health reported its 12th case of human infection of the highly pathogenic avian influenza virus. An 18-year-old girl is hospitalized in stable condition after apparent infection through contact with diseased birds.
Egypt’s Central Public Health Laboratory and the U.S. Naval Medical Research Unit 3, based in Cairo, Egypt, have verified the cases. Of these 12 bird flu cases to occur in the most populous nation of the Arab world, three patients have died, four remain hospitalized and five patients have recovered fully.
Not all the Egyptian cases have been included in the World Health Organization’s official tally of human cases, pending further testing and confirmation. With inclusion of the Egyptian cases, the world occurrence of avian influenza in humans will exceed 200 cases with 110 deaths, occurring in nine nations.
GEOGRAPHIC REACH OF VIRUS EXPANDS
Since the beginning of 2006, the H5N1 virus has appeared in animals in steadily growing numbers of nations, almost 50 now, as tallied by the U.S. Centers for Disease Control and Prevention.
Most of the European nations reporting detection of the bird flu virus have found it in wild birds, not in domestic flocks. However, an OIE report of April 13 cites the destruction of almost 14,000 domestic birds on a German farm and French farmers also have spotted the birds in poultry.
Twenty-five European and Eurasian nations now have detected the virus, with four in Africa, five in the Near East, four in South Asia and the remainder in East Asia where this epidemic began more than two years ago.
For additional information on avian influenza and efforts to combat it, see Bird Flu.
Source: United States Department of State