Have we got it right about bird flu?

Jun 8 2006

Health officials in Indonesia must have breathed a sigh of relief at the the World Health Organisation's (WHO) news that bird flu has been ruled out in the cases of four Indonesian nurses who fell sick after caring for people infected with H5N1 virus.

Indonesian health authorities and the WHO had closely monitored the influenza-like illnesses of the four nurses; two of whom worked in Bandung, West Java and two in Medan, North Sumatra.

The two nurses from Sumatra were a particular worry as they had been involved in caring for members of an extended family, seven of whom died last month from the virus.

The cluster of infections caused alarm that the virus was mutating and becoming better at infecting people.

But the WHO says laboratory tests showed no significant change in the virus, a result that was further confirmed by the nurses' negative diagnosis.

The WHO has confirmed an additional case of the H5N1 avian influenza virus in Indonesia in a 15-year-old boy from West Java who died on May 30.

To date of the 49 confirmed cases in Indonesia, 37 have been fatal.

According to the WHO the virus has killed 128 people and infected 225 others since 2003 and 200 million birds have died or been culled.

The H5N1 virus remains mainly a disease of birds, but experts fear it could change into a form easily transmitted from person to person triggering a pandemic with the potential to kill millions within a short period of time.

All human cases have so far been traced to direct or indirect contact with infected birds.

Many experts believe wild birds are spreading the deadly H5N1 virus but others suggest the spread of the disease is more likely to be down to the poultry industry.

Media coverage of officials in poor, rural third world countries slaughtering flocks of poultry and birds adds to the panic and possibly endorses the view that the wild bird population is the culprit in spreading the virus.

Various reputable organisations, the WHO included, have released a plethora of advice, information and strategies supporting the wild bird and backyard poultry theory, yet the scientific consensus on the origins of avian flu is assumed.

Over the last year an ever increasing number of non-governmental organisations, bird experts and veterinarians have voiced suspicion over the global intensive poultry industry.

The international environmental organisation Grain has directly challenged the official view in a new report and declares that H5N1 is essentially a problem of industrial poultry practices, the epicentre of which is the factory farms of China and south-east Asia.

The report says that the UN agencies at the forefront of the international response to the virus, the WHO and FAO, are pursuing top-down strategies for wiping out bird flu that in turn are wiping out the foundations for long term, pro-poor solutions in the process.

The report highlights how the FAO has turned its back on family poultry farming and contrasts the WHO's lack of concern for the impact of its bird flu measures on small farmers and says the global approach to control bird flu co-ordinated by the UN agencies excludes local communities from decision-making and does not consider the dynamics of the disease in local contexts.

The report maintains that the solution being proposed - a complete shift to factory farming - merely brings us back to the source of the current bird flu crisis.

Although wild birds can carry the disease, at least for short distances, the main infection route is the highly self-regulated transnational poultry industry, which sends its products and wastes around the world through a multitude of channels.

Grain's theory for the emergence of H5N1 has been supported by an editorial in the prestigious medical journal The Lancet which points out that bird flu has coexisted peacefully with wild birds, small-scale poultry farming and live markets for centuries without evolving into a more dangerous form of the disease.

The low-density of outdoor poultry flocks offers plenty of genetic diversity in breeding stock, whereas hi-tech, intensive poultry farms, where as many as 40,000 birds can be kept in one shed and reared entirely indoors produces the perfect environment for spreading the disease and for encouraging the rapid mutation of a mild virus into a more pathogenic and highly transmissible strain, such as H5N1.

Grain says H5N1 is a poultry virus killing wild birds, not the other way around.

This view is supported by the charity BirdLife International, which plots the migratory routes of wild birds and says, with few exceptions, there is a limited correlation between the pattern and timing of the spread of bird flu among domestic birds and wild bird migrations.

The charity also believes that most of the bird flu outbreaks in south-east Asian countries can be linked to the movements of poultry and poultry products.

Intensive poultry farms are notorious for rapidly spreading and amplifying diseases and bugs such as salmonella, campylobacter and Newcastle disease which are already endemic among factory-farmed poultry.

Experts say such birds are genetically similar but their immune systems are compromised by living in conditions of impacted litter and faeces, in close proximity to one another, and sharing the same warm air space, which creates a hothouse for bugs to develop.

Many still suspect the initial source of the virus was in China where intensive poultry farms were using, with government approval, a human anti-viral drug called Amantadine.

This misuse could well have caused the avian flu virus to evolve into the drug-resistant H5N1 strain.

In the event experts say that Amantadine has become useless in protecting people in case of a worldwide bird flu epidemic.

A suspected source could very well be a mass outbreak last year among geese at Qinghai lake in northern China.

Migratory birds were blamed for carrying the virus westwards to Russia and Turkey, but BirdLife International says no species migrates from Qinghai west to eastern Europe and the most likely explanation might be found in the intensive poultry farms whose "poultry manure", a euphemism for what is scraped off the floor of factory farms - bird faeces, feathers and soiled litter - is used as feed and fertiliser in fish farms and fields around Qinghai.

The WHO says that bird flu can survive in bird faeces for up to 35 days and it could be that the virus was passed from intensively reared birds to wild ones via chicken faeces, rather than the other way around.

An outbreak of bird flu in a remote village in eastern Turkey in January was also initially blamed on migratory birds but it later emerged that the birds were intimately connected with a large factory farm nearby.

The Food and Agriculture Organisation (FAO) has now acknowledged that the poultry trade was responsible for the spread of H5N1 in Turkey, going as far as to single out the common practice of intensive poultry farms sending out huge truckloads of low-value, possibly sick birds, to poor farmers.

Despite this when bird flu hit a factory farm in Nigeria in February, the FAO still blamed wild birds even when Nigerian authorities blamed the poultry industry and it was later found that the eggs used by the farm in question were not from registered hatcheries, and may have come from a bird flu-infected country, such as Turkey.

The explosion of intensive poultry production across the world appears to be in line with an increase in outbreaks of avian flu.

In the south-east Asian countries such as Thailand, Indonesia and Vietnam poultry production has expanded to eight times what it was years ago.

Whereas in Laos, H5N1 has been restricted mainly to the country's few factory farms and authorities there have successfully eradicated bird flu by closing it's borders to poultry from Thailand and culling chickens in commercial operations.

Laos has abundant free-ranging chickens mixing with ducks, quail, turkeys and wild birds but almost no contact between its small-scale poultry farms which produce nearly all of its domestic supply.

Despite all the evidence now emerging that wild birds may not be the prime carrier of H5N1, governments are still panicking and in Europe many countries have issued bans or restrictions on the keeping of outdoor poultry.

Environmental organisations insist that this would be an enormous mistake to place all birds indoors and fails to address the root cause of disease.

They say governments should support farming that encourages animal health, so that livestock have naturally robust immune systems developed by contact with, rather than exclusion from, all disease challenge.