Scientists with the University of Maryland School of Medicine are helping to test a vaccine to fight a lethal strain of bird flu that has killed 44 people in China.
The H7N9 strain has not yet been found in the United States, but the medical school's Center for Vaccine Development is among nine sites around the country where researchers are participating in two clinical trials to get the vaccine ready as a precaution in case of a global pandemic.
"If you wait until a pandemic has hit and start testing the vaccine, you are behind the curve," said Dr. James D. Campbell, an associate professor of pediatrics at the University of Maryland School of Medicine and a lead investigator of the study.
Vaccines usually are created ahead of time for strains of flu that show unusual potency or signs that they could become easily transmitted. So far, people infected with H7N9 can pass it on to someone, Campbell said, but that second person hasn't been able to transmit it to a third person.
"If it doesn't make people all that sick or not sick at all, you and I would not be having this conversation," said Dr. Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases, which is sponsoring the study. "The people that do get affected with this strain are at a higher risk of mortality or getting very sick."
The latest strain, which until now has not been found in people, was first detected in February in China, where there have been 135 confirmed cases. Most people were exposed to the virus through contact with poultry.
While the virus is not easily transmitted through humans yet, there are signs that could change.
"People who work in laboratories can determine which genes can be mutated to make it more transmittable, and it looks like it is moving on that path to become more transmittable," Campbell said.
The clinical trials will test the vaccine on healthy adults. Scientists will look at whether the vaccine causes people to form antibodies that would fight off the disease, Campbell said.
The vaccine is made from inactivated H7N9 virus isolated in Shanghai earlier this year. The vaccine won't be tested in time for this year's flu season.
Fauci said the vaccine won't be mass-produced, but instead will be made in small lots.
"It is a precaution to get ready so we know exactly what we need to do if we ever have to mass-produce a vaccine," he said.