FRIDAY, July 15 (HealthDay News) -- New research may bring
scientists one step closer to developing a vaccine that protects
against hundreds of strains of
meningococcus B, the most common cause of bacterial meningitis.
Bacterial meningitis, an inflammation of the membranes covering
the brain and spinal cord, can cause brain damage and death.
Existing vaccines cover four of five types of bacteria that cause
the disease, but developing a vaccine against
meningococcus B has been challenging because more than 300
strains exist.
For this study, researchers with Novartis, the pharmaceuticals
giant, and the University of Florence in Italy bioengineered 54
immunogens, which are substances that can elicit an immune
response. They then tested these immunogens in mice to see which
ones encouraged the development of antibodies when exposed to
diverse strains of
meningococcus B. From there, they tested eight particular immunogens that triggered the best antibody response in a mouse model against a larger, more diverse group of meningococcus B strains. This experiment allowed them to
pinpoint the most effective candidate.
"The cool thing about what these researchers did is that they bioengineered their own variant," said Dr. Alka Khaitan, a pediatric infectious disease specialist at New York University Langone Medical Center in New York City. "The new technology would allow us to look at all the variations and then pick and choose the ones that are likely to be protective."
More study is needed, but if the technology becomes widely
available, it could also foster the development of vaccines for
malaria and HIV, the virus that cause AIDS, she said. HIV and
malaria also have many variations, which has hampered vaccine
development.
The study results are published July 13 in
Science Translational Medicine.
Meningococcal B is highly contagious. Infants are at highest
risk of infection, and if they survive, they may end up with
learning disabilities, hearing loss or loss of limbs, according to
the study. Disease onset occurs so fast that antibiotics are
sometimes unable to stop it.
"We have failed up to now to develop a vaccine, and we have seen epidemics related to meningococcus B," said Dr. Bruce Hirsch, an infectious disease expert at North Shore University Hospital in Manhasset, N.Y.
"In a young healthy person, this strain can cause severe illness or death within hours, so the ability to prevent it in college dormitories, military recruits and crowded conditions is very important," Hirsch said.
Dr. Peter D. Kwong, of the vaccine research center of the
National Institute of Allergy and Infectious Diseases in Bethesda,
Md., and co-author of an accompanying editorial, said the new
technology may one day take the gamble out of developing the annual
flu vaccine. Each year, scientists develop a vaccine based on
projections and predictions.
"If we could develop one that provides quite broad protection against all flu strains, we may be able to have a general flu vaccine, so we don't need a new one every season," he said.
That said, many hurdles remain in terms of developing new
vaccines, including safety and efficacy trials as well as cost and
delivery issues.
More information
For more information about meningitis, visit the
U.S. National Library of Medicine.