Even though, World Health Organization officials say better preparations are in place to combat a potential flu pandemic now, than five years ago, however, the growing number of swine flu cases makes vaccine development a growing concern.  But, if a decision is taken to develop a vaccine for swine flu, it will take many months before becoming available.

According to infectious-disease specialist P.J. Brennan, chief medical officer for the University of Pennsylvania Health System, the present vaccine-making processes are multi-step recipes beginning in the molecular biology labs of international and national health organizations like the Centres for Disease Control and Prevention.

Further, Brennan says one has to begin preparing six to eight months in advance to have vaccines ready for fighting an epidemic or pandemic.

On identification of a virus, one of two FDA-approved methods are used.

In the first method known as the attenuated method, new strains of the virus are grown in chicken eggs.  However, WHO officials say despite current efficiency in developing vaccines than in the past, some infectious-disease experts believe eggs can be unreliable., as Brian Currie, medical director for research at Montefiore Medical Centre in New York say: ‘They can go bad, the strain might not grow fast enough, or at all,’ taking months to harvest the virus.

The second method, Wayne Marasco, associate professor of medicine in the department of cancer immunology and AIDS at the Dana-Farber Cancer Institute at Harvard says, involves using a part of the virus’s DNA to manufacture the vaccine.  Basically, a protein found on the surface of the virus if injected into a patient, causing him to develop anti-bodies and raising his immunity to the virus.

Agreeing with health officials, Marasco says it could take months to make a vaccine to fight this entirely new strain of flu, as: ‘You can’t pull an old virus off the shelf and say it’s 95% similar and hope to get cross-protection.’

However, Currie says medical literature is full of other, more efficient ways to develop flu vaccines, only one would have to re-tool entire production plants to develop these newer methods.

While, federal scientists have the raw material or what they call virus ‘seed stock’ to develop a swine flu vaccine, before they can begin manufacturing, there are many unanswered questions e.g. how many doses of vaccines will be needed, when to produce them, etc.

With the current seasonal vaccine proving ineffective against swine flu, already 28 confirmed cases have been reported in New York, including 20 others across four other states.  However, CDC is considering three major fall vaccine options:
1.    A vaccine specifically for swine flu only.
2.    Substituting one of the three strains in the seasonal vaccine with a swine flu dose.
3.    Or, adding swine flu as a fourth strain to the vaccine i.e. a four-tiered or quadrivalent flu vaccine.

It remains to be seen what is ultimately decided as the flu season approaches.