The Meningitis Vaccine Project recently announced that it will soon begin clinical trials of a vaccine for Meningitis A that is designed to be commercially viable in the developing world where the disease has reached near-epidemic proportions in some countries.
A number of vaccine candidates for Meningitis A have been produced in the past but along with being too expensive for developing countries, they tended to offer only short term protection from the disease and did not work at all in the most vulnerable population — young children.
The newly developed vaccine candidate would likely cost under $1 per dose and researchers believe it will provide long term protection even when give to young children.
Dr. F. Marc LaForce of the Meningitis Vaccine Project told the BBC,
Clinical trials for the new vaccine could start as early as 2004 and the new vaccine could be ready for wide use in sub-Saharan Africa within the next four to five years . . . Our goal is to eliminate epidemic meningitis as a public health problem in sub-Saharan Africa, thereby alleviating the social, human and economic disasters these epidemics cost.
In sub-Sharan Africa, Meningitis A kills 5,000 people in non-epidemic years, and epidemic outbreaks have claimed upwards of 20,000 dead annually.
The development of this vaccine owes much to animal research. It is an offshoot of an effective Meningitis Hib vaccine introduced in Finland which effectively solved one of the major hurdles — providing long term effectiveness. Previous vaccines were based on a sugar, PRP, that is present on the surface of the meningitis bacteria. Because of the nature of PRP, however, the immune response to it was short lived.
Animal studies had shown, however, that if PRP was bonded to a protein that the immune response was much more powerful. This conjugation technique was applied to a vaccine for human beings which has reduced Meningitis Hib rates by 60 to 80 percent where it has been used.
The experimental meningitis A vaccine bonds a sugar present on the surface of the bacteria with a tetanus protein — which the immune systems of even very young children recognize — to elicit an immune response.
Sources:
Meningitis A vaccine hope. The BBC, March 18, 2003.
Milestone Reached in 100-Year War Against Meningitis. Press Release, Meningitis Vaccine Project, March 17, 2003.
Hib meningitis vaccine. Research Defence Society.
Vaccine to Fight Meningitis in Africa Ready To Be Tested. David McAlary, Voice of America, March 18, 2003.
Vaccine hope for meningitis A. Rebecca Oppenheim, HMG, March 20, 2003.