Avian Influenza Infection In Birds Spreads To Turkey, Romania

In Romania, investigations of recent poultry deaths have, to date,identified the H5 subtype of avian influenza virus. Further testing isunder way to determine the strain and whether the virus is highlypathogenic. Authorities in the two countries have undertaken controlmeasures as recommended by OIE and FAO. WHO is sending diagnosticreagents and other supplies to support testing in nationallaboratories. Viruses from both outbreaks have been sent for furtheranalysis to the Central Veterinary Laboratory Agency-Weybridge (UK),which is an OIE/FAO reference laboratory. Viruses are also being sentto WHO reference laboratories for comparison with human H5N1 isolatesfrom Asia.

Public health implications

The spread of H5N1 to poultry in new areas is of concern as itincreases opportunities for further human cases to occur. However, allevidence to date indicates that the H5N1 virus does not spread easilyfrom birds to infect humans. WHO advises countries experiencingoutbreaks in poultry to follow certain precautions, particularly duringculling operations, and to monitor persons with a possible exposurehistory for fever or respiratory symptoms. The early symptoms of H5N1infection mimic those of many other common respiratory illnesses,meaning that false alarms are likely.

The WHO level of pandemic alert remains unchanged at phase 3: avirus new to humans is causing infections, but does not spread easilyfrom one person to another.

WHO continues to recommend that travellers to areas experiencingoutbreaks of highly pathogenic H5N1 in poultry should avoid contactwith live animal markets and poultry farms. Large amounts of the virusare known to be excreted in the droppings from infected birds.Populations in affected countries are advised to avoid contact withdead migratory birds or wild birds showing signs of disease.

Direct contact with infected poultry, or surfaces and objectscontaminated by their droppings, is considered the main route of humaninfection. Exposure risk is considered highest during slaughter,defeathering, butchering, and preparation of poultry for cooking. Thereis no evidence that properly cooked poultry or poultry products can bea source of infection.

Countries located along migratory routes need to be vigilant forsigns of disease in wild and domestic birds. Recent events make itlikely that some migratory birds are now implicated in the directspread of the H5N1 virus in its highly pathogenic form.