SocialismToday           Socialist Party magazine

Issue 81 - March 2004

Bird flu

WHEN IT comes to mass destruction, a strong contender for the all-time record must be the 1918-19 ‘Spanish flu’ virus. Flourishing under the impoverished conditions that followed the first world war, the epidemic (which did not actually start in Spain) killed 40-50 million people worldwide. Scientists believe it is a matter of time before another influenza virus poses a similar threat to humanity.

The current East Asian bird flu is the most recent of similar outbreaks. In 1997 in Hong Kong 1.4 million chickens, the entire stock, were destroyed. Eighteen people became infected of whom six died. A further outbreak in 1999 saw 1.25 million birds culled. In 2003 the Netherlands was hit by an outbreak that killed one veterinary surgeon and led to a mild illness in 83 poultry workers and members of their families. Different strains of virus have been responsible in each case.

New cases came to light this January in Thailand and Vietnam, but have now been reported among the bird populations of Japan, South Korea, Laos and Cambodia. The Indonesian authorities covered up the outbreak but have now been forced to admit that the virus was found last August. Since then, 4.7 million birds have died there but, according to the government, only 60% as victims of bird flu or the cull to contain it.

Thailand has also been in involved in a cover-up, slaughtering nine million chickens since November but not admitting a case until the third week of January, when two young boys died. ‘The government knew’, the father of one said, ‘so why didn’t they tell the public so that we could protect ourselves?’

Strong pressure was exerted to conceal the outbreaks as chicken exports are worth $1 billion a year to Thailand and up to $7 billion a year to Indonesia. Much of this ends up as processed chicken in Europe. Over 80 million chickens have been slaughtered so far. Financial markets in East Asia have fallen slightly. ‘I think the concern with investors is whether this becomes a SARS-like situation’, said Peter Haines of Aberdeen Asset Management in Singapore. ‘I guess that would only come about if we suddenly discovered that this disease can be passed on from human to human. That clearly would have big economic implications for the region’.

There is evidence that all the outbreaks may have originated in China, where a further cover-up has taken place since the first half of 2003. As the main method of disease prevention is to slaughter all poultry in the affected area, any delay allows the virus to spread. The effect on the livelihood of small farmers can be devastating. Poultry smuggling from China may have spread the outbreak around neighbouring countries. Thai government compensation to farmers is only 10% of market rates, so farmers are reportedly rushing to sell their birds before the cull is widened, spreading the virus further.

Live-animal (wet) markets are traditional in many countries. These provide an additional method of spread between infected birds, with large numbers of people in close contact with them. Hong Kong has introduced two clean days a month, when the markets are closed, cleared of all birds and animals, and cleaned. This has reduced the numbers of different influenza virus strains present compared with China, where these steps have not been taken. Last year’s SARS virus is also thought to have spread from wet markets. But where most people have no refrigeration, wet markets cannot simply be closed down.

World Health Organisation (WHO) officials have warned that the disease is spreading at an unprecedented speed. ‘We don’t know how this virus is spreading, and so it’s safe to presume that nowhere can consider itself safe’, a spokesman said. So far there is no evidence that the strain of virus causing the current outbreak is spreading among humans. Fourteen people had died in Vietnam and six in Thailand by 17 February, but with no clear case of human-to-human transmission occurring.

One way to cut the risk of the virus developing human infectivity would be to vaccinate against human influenza all those working in the poultry industry, including those involved in the culls (which have included prisoners and the armed forces in some countries). Anti-viral tablets can also be given to prevent flu, but they are expensive. Vietnam had a stock of 100,000 tablets of Tamiflu (made by pharmaceutical giant Roche) and a similar amount of human vaccine – ‘a drop in the bucket’, according to the WHO.

A vaccine against the strain of bird flu virus responsible for this outbreak would help prevent it causing an epidemic in humans. Because the virus can change so rapidly new vaccines need to be continually developed to keep up with these changes. A genetically engineered ‘seed’ virus with the same surface proteins as the current strain was expected to be ready within two months. From this, 750 million doses could be produced in several months, growing the seed strain in fertile chicken eggs. But to find enough eggs, the manufacturers would have to stop producing normal human flu vaccine, increasing the risk to the elderly and others who get vaccinated each autumn.

Vaccines can be produced with human cultured cells instead of eggs. A factory in the Czech Republic – opened in 2002 by the US company, Baxter – could produce 50 million doses this way. It is ironic that they are still unavailable, especially as a mild strain of bird flu broke out in Delaware, USA, in early February. But the company has been co-opted to make smallpox vaccine for the US ‘war on terror’ bio-defence stockpile.

Jon Dale

INFLUENZA VIRUS causes epidemics because its surface proteins can change rapidly as it reproduces. This means that it can evade the immunity that its ‘host’ has acquired from previous infections. The host’s immune system does not recognise the new virus’s surface.

The natural reservoir of the influenza A virus is water birds and wildfowl. In the wild, where ducks, geese, etc, are thinly spread, the virus tends to cause mild disease – it would soon die out if it killed its hosts. But where there is an abundance of birds in one place, the virus can change to become a killer – the faster it reproduces the more successful it is and there are plenty of hosts to replace those it kills. Industrial-scale poultry farming provides ideal conditions for this to occur, with birds in crowded conditions also suffering stress, lowering their immunity. Some attempts have been made to blame wild birds for the current outbreak, but migrating birds monitored in Thailand were free of the virus. Wild birds have been affected only where poultry outbreaks have occurred.

Although a bird virus may infect humans, unless it changes so that it can move from human to human, its threat is limited. But if anyone already has human flu when they become infected with bird flu, the viruses can reassort (mix) their genetic material. This could result in a virus able to transmit between humans, evading all immunity humans have from previous flu infections or vaccinations.

Experts predict that it is a matter of time before a pandemic occurs on the scale of 1918-19. (There were less severe epidemics in 1957 and 1968.) In the advanced industrialised countries it would cause 57-132 million doctor visits, 1-2.3 million hospital admissions, and 280,000-650,000 deaths over less than two years. In poor countries with few health services, the situation would be far worse.

Socialism will never stop new strains of viruses posing grave threats to human health. But farming practices would be geared to minimise the risk of the rapid spread of new viruses. The resources of a publicly owned pharmaceutical industry would also be marshalled to develop and produce the vaccines and treatment needed. And planning of public health would ensure preventive action, with those at risk properly protected.


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