Bird Flu Flares Up Anew

Health officials worry that the high infectious H5N1 bird flu virus could mutate into a virus that is easily spread among humans, triggering a global flu pandemic that could kill millions of people.

"The virus has not become more contagious to humans but has managed to persist in parts of Asia, Africa and probably Europe. It could still trigger a human influenza pandemic," warned FAO's Chief Veterinary Officer Joseph Domenech.

The Indonesian Ministry of Health announced the death today of a previously confirmed case of H5N1 infection in a 30-year-old man from Tangerang District, Banten Province. Of the 120 cases to date in Indonesia, 98 have been fatal.

Of the 353 human cases of avian flu in 14 countries since 2003, the World Health Organization reports that 221 people have died of the disease.

In her annual report January 21, Dr. Margaret Chan, director-general of the World Health Organization, said, "Many Regional Committees also addressed the threat posed by avian influenza. This season has again given us some stark reminders that the threat of an influenza pandemic has by no means diminished."

Chickens for sale in Bali, Indonesia (Photo credit unknown)

"Globally, much progress has been achieved in keeping the H5N1 avian influenza virus under control," Domenech said. "Surveillance, early detection and immediate response have improved and many newly infected countries have managed to eliminate the virus from poultry."

"But the H5N1 avian influenza crisis is far from over and remains particularly worrying in Indonesia, Bangladesh and Egypt, where the virus has become deeply entrenched despite major control efforts," he said.

Bangladesh, Benin, China, Egypt, Germany, India, Indonesia, Iran, Israel, Myanmar, Poland, Russia, Ukraine, Turkey and Vietnam have confirmed new H5N1 outbreaks in poultry, including chickens, turkeys, geese and ducks.

Except for a few cases in wild birds in China, Poland and United Kingdom, most of the confirmed outbreaks occurred in domestic poultry.

Commenting on individual countries, Indonesia remains one of the worst affected countries with 31 out of 33 provinces infected since 2004, and many are heavily infected.

"The continuing number of human cases gives cause for concern," Domenech said.

"We have observed that new H5N1 avian influenza virus strains have recently emerged in Indonesia with the possible effect that vaccines currently in use may not be fully protecting poultry against the disease," he said. "This requires more investigations and the development of better poultry vaccines," he said.

Indonesia has vaccinated millions of chickens against H5N1 bird flu virus. (Photo courtesy FAO)

The government of Indonesia and FAO, on behalf of the network of international reference laboratories operated by the FAO and the World Organization for Animal Health, are working on a virus monitoring program to examine the problem more carefully.

Domenech said that India is struggling to keep the worst-ever avian influenza outbreak in West Bengal under control.

In Bangladesh, 21 out of 64 districts have been infected with H5N1 and the situation seems to be worsening. The disease appears to be endemic in the country, and surveillance and control campaigns have so far not succeeded in interrupting virus transmission between provinces. FAO is strengthening its presence in Bangladesh to support the government in its efforts to bring the disease under control.

Egypt has stepped up the fight against avian influenza, but recent outbreaks indicate that control efforts need to be strengthened, Domenech warned.

"The reporting of new outbreaks in poultry, disinfection, culling, movement control and biosecurity on farms and markets remain insufficient and need to be improved. Vaccination campaigns had been generally successful on commercial farms, but not among small-scale producers," Domenech said.

Following the initial success of vaccination on industrial poultry farms, the control measures may have slackened. The disease was thus given an opportunity to reappear in the industrial sector seemingly resulting in a wider redistribution throughout the country.

Domenech also confirmed that the potential change of virus strains should be further investigated. FAO is working closely with the government of Egypt in strengthening all aspects of disease detection, control and communication.

In West Africa, Benin, Ghana, Nigeria and Togo have had outbreaks in 2007. There is a serious risk that the virus becomes well established in the region, Domenech warned.

"Virus circulation in Nigeria could be a potential source of infection for neighbouring countries despite intense efforts from the Nigerian government to control the disease in poultry," he said. FAO continues to work closely with the governments in the region in improving disease control.

In Europe, Germany, Poland, the Russian Federation and the United Kingdom reported new avian influenza outbreaks recently.

"The detection and immediate response in all countries, especially in the European Union, is very effective," Domenech said. "But we are seeing virus infections in poultry that are not transmitted by wild birds. This raises questions about other ways of virus transmission and potential reservoirs of infection, like in free ranging ducks," he added.

With FAO's assistance, more than 50 countries have been able to control and eliminate the disease in poultry.

"Surveillance and immediate control interventions, biosecurity, proper vaccination and culling and the strengthening of veterinary services are key elements for successful H5N1 avian influenza control campaigns," Domenech said.

Copyright Environment News Service (ENS) 2008. All rights reserved.