Flu Hits Australia; Obese Stricken; Stronger Vaccine Needed

by Lynn Shapiro, Writer | July 15, 2009
Obesity has been observed
to be one of the risk
factors for more severe
reaction to H1N1 swine
flu virus.
As swine flu takes its toll in the Southern Hemisphere, six young people are on life support in a Sydney, Australia hospital. Their lungs aren't responding to regular ventilation.

The Medical Journal of Australia has detailed the cases of five people in Melbourne whose conditions point out the small but serious risk of swine flu causing life-threatening respiratory failure.

Meanwhile, at a WHO meeting last week, Dr. Marie-Paule Kieny, director of the Initiative for Vaccine Research recognized that the H1N1 pandemic "is unstoppable and therefore, that all countries need access to vaccine."

Last week, WHO reported nearly 95,000 cases of swine flu worldwide including 429 deaths. Most people who get the virus only experience mild symptoms and don't need medical attention.

Obesity a Factor

Obesity has been observed to be one of the risk factors for more severe reaction to H1N1--something never before seen, Kieny said. It's not clear whether obese people may have undiagnosed health problems that make them vulnerable to this stain of flu, or if obesity is a risk factor in and of itself.

On Friday, a team at the CDC and the University of Michigan reported that nine out of 10 patients treated in an intensive care unit there were obese. They also had unusual symptoms, such as pulmonary embolisms and organ failure. None of the patients has recovered and three have died.

Half as Much "Yield"

Kieny told experts at the WHO meeting that officials would also try to get more robust viral strains to companies making vaccines. She said the strains that had been given to vaccine makers did not grow well in the chicken eggs used to cultivate them.

One exception, she said, is AstraZeneca's MedImmune unit, which manufactures a live virus that is squirted into the nose and is easier to produce.

Because the viral strains are weak, a vaccine might not be available until the end of the year, Kieny said. So far, the swine flu viruses being used are only producing about half as much "yield" as regular flu viruses, she noted.

U.S. Update

The Obama Administration's campaign to start vaccinating as many people as possible--beginning with health care workers--might be risky, she added. Until millions of people start getting the medicine, experts will not know if the vaccine causes potentially dangerous side effects.

To boost the vaccine's potency, several vaccine makers are considering using adjuvants. But little or no data exists on the safety of vaccines with adjuvants. Certain populations, including children and pregnant women, would be most vulnerable to the revved-up shots. In the U.S., there are no flu vaccines that use adjuvants.