May 31, 2006

 

US researchers compare lessons learnt from swine flu with bird flu

 

 

Growing interest in bird flu is resurrecting memories of a long past pandemic that is etched in the minds of only a few Americans, and US scientists are poring over records to see what can be gleaned from its previous experience.

 

The Swine Flu from 1976 was an H1 flu, a less contagious strain, than the H5 flu now, said the University of Minnesota's Dr Kurt Rossow.

 

In 1976, the death of an army private from swine flu sent millions of Americans for Swine Flu shots at public clinics. Tests at the same camp indicated that 500 other soldiers had the Swine Flu, although none became ill. Health officials announced that the Swine Flu was able to transmit from person to person, threatening a pandemic.

 

Mindful of the fact that the last pandemic in 1918 killed nearly 20 million people, a programme was launched to vaccinate all 220 million Americans, but it was stopped after mass pandemonium led to 40 million people given the shots using jet guns to accelerate the process. Hundreds became seriously ill from the innoculations and at least 25 died.

 

Now, researchers at the University of Minnesota's Veterinary Diagnostic Laboratory are focusing on pigs as they can carry both human and bird flu viruses.

 

Dr Rossow said that recent work suggests that new flu viruses found in pigs have actually been pre-existing in the human population and there have not been concerns that there was any human virus that had been mixing with a pig and jumping back to infect humans. 

 

Scientists say a pig to people jump is very rare and pigs are more in danger of catching a human flu than the other way around. The fact that the virus can migrate from birds or pigs to people is not the big fear.

 

Scientists are pondering why the Swine Flu did not go pandemic thirty years ago and said it probably stalled because it had been around in people for decades before, thus creating some immunity and making it difficult for the virus to spread person-to-person.

 

The H5 bird flu has apparently not been seen widely in humans before and there may be little, if any, immunity to it.

 

The deaths of 7 members of one family in Indonesia from the H5 bird flu last month is worrying health officials.

 

The World Health Organization's Peter Cordingley said so far an animal source for the infection could not be found and that is a source of great concern as it could mean that the virus has mutated into a form that can pass between people.