Influenza A: 'Jabs won't give protection'

NST: KUALA LUMPUR: The flu vaccine jabs to be given to some 200,000 of the country's frontliners will not protect them from the pandemic influenza A (H1N1) virus, but they can help in identifying potential cases.
Prominent virologist Prof Emeritus Datuk Dr Lam Sai Kit said the vaccination could help filter out those suspected to be infected with the mutated H1N1 virus strain as the vaccine could not protect them against it.
"If they come down with flu-like illnesses even after being jabbed, then one would be more suspicious because they shouldn't be coming down with ordinary flu.
"It could be a new strain which is not covered by the existing influenza vaccine," he told Bernama yesterday.
Lam, who is currently with Universiti of Malaya's Institute of Research Management and Monitoring, said the existing influenza vaccine covered three different viruses but the composition of the vaccine changed every year.
"The current vaccine contains the latest strain of influenza A, the H3N2, and the latest strain of H1N1, as well as influenza B.
"However, the H1N1 strain in the vaccine is not going to protect against this mutated strain of influenza."
He advised the public not to get panicky and view every flu-like case as that caused by the mutated H1N1 strain.
"You must remember that there are flu cases going on in every country all the time."
Lam, who was instrumental in the discovery of the Nipah virus, said he understood the public's concern as the virus was believed to have spread initially through pigs to humans and transmission was now human to human.
He said viruses were usually species-specific, meaning that they could not jump between species.
Lam said even in rare cases of bird flu, where a human was infected through contact with an infected bird, the virus could not be easily passed on to another person, causing the illness to come to a "dead end".
However, Lam said, pigs could facilitate "genetic exchange" between viruses as they could carry more than one virus strain.
"When you have more than one virus strain in an animal, you call it the mixing bowl. This is a fantastic way of genetic exchange and when the virus replicates in the pig, there is a very high chance of them acquiring human and other animal genetic materials."
This acquisition would help the new mutated strain survive longer in the human body and pass it on, thus increasing the possibility of human to human transmission.
Although there are small numbers of influenza A cases among humans in the past, the cases had been mild and recovery usually uncomplicated.
However, the current mutated strain contains genetic elements from swine, avian and human, and is resistant to several common amantadine drugs, and the current seasonal influenza vaccine cannot prevent influenza A.
Fortunately, Lam said, drugs such as oseltamivir (marketed as Tamiflu) and zanamivir (marketed as Relenza) were still useful to treat such cases but should be used only if prescribed by a doctor as indiscriminate use could lead to resistance to the drugs.
Lam is also the past president of the Asia-Pacific Society for Medical Virology and also the former director of the World Health Organisation's National Influenza Centre (Malaysia).