Experts meeting at the World Health Organization say drug manufacturers will be able to sharply increase the amount of bird flu vaccine they are able to produce in the coming years. They say recent scientific advances and increased vaccine manufacturing capacity will make this possible. But they warn that an effective bird flu vaccine is still under development. Lisa Schlein reports for VOA from Geneva where the first meeting of a WHO advisory group on pandemic influenza vaccine production was held.
The World Health Organization says last year, vaccine manufacturers reported they would be able to immediately produce about 100 million courses of pandemic influenza vaccine based on the current H5N1 avian influenza strain.
Experts attending the WHO meeting say they now anticipate that global production capacity will rise to 4.5 billion pandemic immunization courses a year in 2010.
Director of the Initiative for Vaccine Research at WHO, Marie-Paule Kieny, calls this significant progress. "But, this is not quite yet what we need to have because really the target of WHO and of most public health officials would be to be able to immunize the whole planet, which is 6.7 billion people. And, preferably in no more than six months because, as I am sure you have heard and seen in the press, that a pandemic if it occurs, is thought to be occurring in waves. So, you would have a first wave and then a second wave and then a third wave eventually," she said.
If drug companies are able to manufacture new doses of bird flu vaccine in six-month cycles, Kieny says there would be enough vaccine available to immunize people who were missed during the first wave of the pandemic.
She says drug companies will have to increase their yearly production of the seasonal flu vaccine currently on the market to one billion doses. She says this would give the pharmaceutical companies the capacity to produce enough bird flu vaccine to protect 4.5 billion people, because a bird flu vaccine is simpler in composition than the annual flu vaccine now available. If a pandemic were to occur, she says manufacturers would stop making the seasonal flu vaccine and switch to producing pandemic vaccine.
Scientists in the U.S. and Europe are currently testing a vaccine on humans that would protect against the deadly H5N1 strain of bird flu. in some of the trials, the people who received the vaccines produced antibodies. But if the H5N1 virus mutates, the current vaccine may not work when a pandemic breaks out and it will have to be fine tuned.
"We do not know for the time being exactly what would be the pandemic vaccine otherwise we would already have a pandemic and we would already be making pandemic vaccines. But, we do not know until the beginning of a pandemic exactly which strain it would be. It is possible that it would be H5N1 because this is the type of virus which is circulating in bird populations. If the pandemic would start now with the H5N1 strain, it is thought that the vaccine which has been developed by the industry?the prototype would protect against this," said Kieny.
The H5N1 virus has killed hundreds of millions of birds. More than two hundred people who were in close contact with infected birds have died. Health experts are afraid millions of people could die if the deadly bird flu virus mutates into a form that allows it to spread from one person to another.