Bird flu closing in: A threat to both chickens and humans

The Straits Times, Asia News Network, Singapore

The spread of bird flu afflicting humans is getting uncomfortably close to Singapore. Thailand and Indonesia reported at the weekend mass infections among poultry. In Thailand one person, a child, has died of the ailment and another child is confirmed sick with bird flu. Health authorities there have reported 10 more suspicious cases, of whom four have died.

If tests under way verify even some of these to be bird flu cases, alarm bells will start ringing across Southeast Asia. Arresting the trend would depend greatly on quick disclosure of outbreaks and culling of chickens -- the only known mass prevention method -- even though the World Health Organization (WHO) confesses it has to rely on guesswork on the probability of the virus mutating into a human-to-human pathology.

So far, it has been bird-to-bird. In rare cases, it has been bird-to-human such as in the 1997 outbreak in Hong Kong which left six persons dead. As with China's tardy response to the Sars outbreak, there will be recriminations about Thailand and Indonesia assuming for too long that poultry sicknesses on commercial farms were caused by agents other than the bird flu virus.

It is accepted that national health authorities have a responsibility to their citizens to not cause alarm with sloppy reporting. But this is a crisis in evolution, much like Sars was. It is safer to assume the worst and prepare for it, than to hope for the best.

Although Vietnam and Thailand are the only countries so far to have had cases of human fatalities, the rapid spread of the virus through bird populations (ducks also are affected) across borders must increase the risk of human infestation.

This has to be Singapore's greatest concern. The cordon sanitaire which the Agri-Food and Veterinary Authority (AVA) has run up around the island through select import bans can still be breached. Scientists speculate that migratory wild birds carrying the bird flu virus or other flu viruses can spread infections in farm poultry far and wide, well beyond human control.

This is a plausible explanation for the rapid morbidity through the region despite swift import bans being imposed to stop cross-border transmission. Smuggling also is implicated, but realistically it cannot account for much of the spread. When Vietnam reported the new outbreak last month and it moved northwards to North Asia, Singaporeans would have felt smug.

Not now, with human contagion so close by. Not only that, but Pakistan's disclosure yesterday of what it said was a milder form of bird flu infections dating to November last year shows a randomness about the pattern of spread that is unnerving.

WHO also reports mysterious deaths of hundreds of farm chickens in Laos, which has been spared so far. If this was bird flu, Laos would be ill-prepared to prevent its spread to Myanmar and densely populated south-western China.

Yesterday's announcement by the AVA of more stringent measures at local farms is commendable. It has done well to place farms off-limits to non-essential personnel and requiring workers to wear protective clothing. WHO says direct contact with sick birds without adequate protection (it has in mind massive burn-and-bury culls with workers wearing face masks but no eye protection) increases the risk of infection.

It is thought the virus is transmitted by inhaling dried particles of droppings. Singapore should consider widening the import ban to all live poultry, including from countries free of infestation. In the current murky state of knowledge about the disease, this is no deprivation.