Sonny Inbaraj
ULAN BATOR, Nov 22 2006 (IPS) – Each time Oranchimeg Bat sees a migratory bird in her poultry farm just outside the Mongolian capital, it sends shivers down her spine.
These birds carry the H5N1 virus that causes highly pathogenic avian influenza, she told IPS alarmingly. We try to keep them off the farm. They re bad and can cause my chickens to fall sick.
Indeed poultry farming is big business for Oranchimeg who has 4,500 imported broilers from Russia and China, kept indoors in battery cages with artificial lighting. The Mongolian poultry farmer sees an income of over 450 U.S. dollars a day from the sale of eggs to supermarkets around Ulan Bator and the last thing she wants is for bird flu to jeopardise that.
Oranchimeg s farm is what the U.N. Food and Agriculture Organisation (FAO) would term as a sector two farming type where poultry production is on a commercial scale with moderate to high bio-security; where the birds are kept indoors continuously and prevented from being in contact with other poultry or wildlife.
Though Oranchimeg s chickens are protected from wild birds, water from a nearby lake that is pumped to her farm for her poultry is not. And that really worries her.
I saw a Ministry of Food and Agriculture public service announcement on TV that wild birds could spread the bird flu virus through water from their droppings, she said emphatically.
Related IPS Articles
Because of this I m constantly monitoring the health of my chickens and vaccinating them once every three months with the help of Veterinary Department field workers, she added.
According to Prof. D. Otgonbaatar, executive director of Mongolia s Centre of Communicable Diseases with Natural Foci, the H5N1 avian influenza virus has adapted to the environment in such a way that it uses water for survival and to spread.
The water in turn influences movement, social behaviour and migration patterns of water bird species. It is therefore of great importance to know the ecological strategy of influenza virus as well, in order to fully understand this disease and to control outbreaks when they occur, he said in an interview.
Landlocked Mongolia, which shares common borders with Russia s Siberia and China, is in the flight-path of wild birds that fly through cold winter skies to warmer lands. Many scientists believe migrating wild birds are responsible for carrying the H5N1 virus from Asia and Siberia to Romania and Turkey.
And although some argue there is not enough evidence yet for firm conclusions, the theory is gaining ground. Scientists are increasingly convinced that at least some migratory waterfowl are now carrying the H5N1 virus in its highly pathogenic form, sometimes over long distances, and introducing the virus to poultry flocks in areas that lie along their migratory routes, the World Health Organisation said early this year.
In August 2005, the Mongolian Ministry of Food and Agriculture reported that 80 migratory birds which were found dead at Erkhel Lake in Kovsgol province near the Russian border were killed by the H5N1 avian influenza virus. Laboratory diagnosis of the wild ducks, geese and swans that were found on Aug. 2, 2005 confirmed they died from Type A bird flu.
In neighbouring China, from April to June, 2005 more than 6000 migratory birds have been reported to have died due to H5N1 infection at the Qinghai Lake Nature Reserve in Qinghai Province. This included bar-headed geese, great black-headed gulls, brown-headed gulls, ruddy shelducks and great cormorants. In Tibet, the death of 133 breeding hens was reported and H5N1 was isolated from samples from these birds.
These new outbreaks suggest that this highly pathogenic H5N1 virus is spreading progressively north-westwards and not restricted to the Southeast Asian focus, where the outbreaks of AI started in mid-2003, explained Prof. J. Bekhochir from the Ministry of Food and Agriculture s Veterinary Institute.
In Russia and Kazakhstan, contact between domestic poultry and wild waterfowl at open water reservoirs is considered the primary source of infection for poultry, he told a seminar organized jointly by the United Nations Children s Fund and the U.S.-based media development NGO Internews, with support from the Japan government.
Though the H5N1 avian influenza virus mostly affects birds, it can occasionally jump species and infect people. It has infected 258 people in 10 countries Thailand, Vietnam, Indonesia, China, Turkey, Azerbaijan, Iraq, Egypt, Djibouti and Cambodia and killed 153 of them.
Experts say the danger is that the virus will evolve just slightly into a form that people can easily catch and pass to one another, in which case the transmission rate would soar, causing a pandemic in which millions of people could die.
A deep concern in Mongolia is also the possible cross-species jump of the H5N1 virus to horses, revered in folklore as helping fierce Mongol warriors led by Genghis Khan conquer Asia riding on their backs. According to FAO livestock figures, there are about 2.2 million horses in Mongolia that has a human population of 2.79 million.
It is widely known that horses are susceptible to two relatively host-specific influenza A virus, H3N8 and H7N7. But virologists have also discovered that receptor specificity for influenza viruses in horses and birds are the same that is the avian influenza virus recognises sugars ending in alpha 2-3 linkage sialic acids that are also found in horse cells.
And this deeply troubles Prof. Otgonbaatar.
The habitat of Mongolian horses and migratory birds overlap as they share common water sources. If H5N1 virus is present in migratory birds there is potential for horses to be exposed to this virus via contaminated water, he pointed out.
The Mongolian government has started research to see if horses are susceptible to the H5N1 virus with the help of agencies like FAO and funding from the Japanese government.
Urgent surveillance is needed around lake areas which are also shared by horses and we hope to get more funds from international donors to be able to do that efficiently, added Prof. Otgonbaatar.