Scientist kept his eye on flu viruses in hunt for vaccine

How do you get a flu virus to grow?

That may seem like a peculiar question -- especially as the flu season approaches -- but it is the one that Dr. Edwin Kilbourne has dedicated his 60 years as a scientist trying to answer.

"My effort was to make the influenza virus grow better so that more virus was available," he said.

A tall, patrician-looking man at age 82, Kilbourne, who recently retired from the department of microbiology and immunology at New York Medical College in Valhalla, explained this to a recent visitor with the precision and helpful care of a man trying to introduce the alphabet to an illiterate. Kilbourne and his lab supervisor of 40 years, Barbara Pokorny, have been two of a handful of scientists worldwide who worked each year to "read" the highly changeable influenza virus and develop a vaccine to knock it out.

"He has been involved in every aspect of preparing vaccines for the influenza season," from understanding the genetics of the virus, to manipulating it to create a version that will grow in eggs, to helping to make the recommendation of what the vaccine formulation should be each year, said Dr. Roland Levandowski, supervisory medical officer for the Center for Biologics Evaluation and Research at the federal Food and Drug Administration. Levandowski said he knew Kilbourne, a member of the National Academy of Sciences and the American Philosophical Society -- two of the most prestigious groups for a scientist -- "way back in the '70s when I was a little whippersnapper, and by reputation before that."

The flu virus is a wily creature. In order to survive, strains change constantly. That means that the vaccine must change each year to be effective -- one of the reasons why we must get a flu shot each year. And that means that scientists must anticipate, based on what strains are being reported in Asia, South America and other areas, what flu strains are likely to hit us during our flu season, which usually peaks in late December to early March. This has to happen early enough to give vaccine manufacturers time to make the vaccine and ship it. (The vaccine contains three virus strains, two Type A strains and one Type B.)

And this is where Kilbourne has played such a key role. The vaccine works by introducing killed parts of flu virus strains into our system. This sets off an immune response so that our bodies will be ready for any subsequent attack by a live virus. But that means you have to grow the virus to make the vaccine: The current method is to use chicken embryos.

The flu routinely kills 20,000 people a year in this country, but it is a flu pandemic like the one of 1918 in which more than 20 million died worldwide that worries experts such as Kilbourne, who has been a member of one government influenza advisory group or another dating back to 1959.

"It may never happen again; I don't like to be like some of my colleagues and say it's a certainty," he said.