Tuesday, November 3, 2009

Swine flu vaccine originates in upstate labs

VALHALLA - Most of the world's H1N1 vaccine started in 30 chicken eggs kept here in a warren of cluttered labs at New York Medical College.

Working seven days a week, microbiologist Doris Bucher and her eight assistants made "seeds" that manufacturers around the globe are using to grow the vaccine used in the swine flu shot.

"It was very intense," Bucher said. "We all knew how important this was. The world was resting on our shoulders."

Bucher and her team did what they always do: take an isolated H1N1 flu strain and allow it to exchange genetic parts with another flu known to grow well in chicken eggs with embryos. The new hybrid would be the vaccine seed.

Production problems delay millions

The seed, designated NYMC X-179, proved a robust grower in the lab. But it was a different story for some of the manufacturers charged with producing 250 million doses of H1N1 vaccine ordered by the U.S. government. They found that the vaccine didn't grow as quickly as typical seasonal vaccine. The delays are being blamed not just on the slow-growing vaccine, however, but on overly rosy projections by federal health authorities. The problems with the egg method have highlighted the push for other vaccine-production approaches, including a cell-based technique that has more than $1 billion of government money behind it.

Initially, the government said 120 million doses of swine flu vaccine would be available by mid-October. Dr. Thomas Frieden, the director of the Centers for Disease Control and Prevention, said on Friday that 26.1 million doses are available.

"It was too optimistic given that it was a biologic product relying on fertilized hens' eggs," said Dr. Robert Belshe, director of the Center for Vaccine Development at St. Louis University.

Making vaccine seed using chicken embryos - a method developed more than 50 years ago - might seem quaint, especially in the face of a global flu pandemic. But Bucher said the technique continues to outperform newer approaches. And last week, Frieden called it "tried and true."

Bucher's lab received some of the new swine flu virus only weeks after it was first identified in April. The team came up with a seed for the vaccine 23 days later. Normally, the process takes at least a month or longer. The seed was then sent in May to the CDC, where it was tested then distributed to vaccine makers.Read More..