
A child waits to receive a vaccine at MRC Laboratories, Fajara.
Every 8 to 10 years, the group A infection sweeps through 21 sub-Saharan nations collectively named the ‘meningitis belt’ that stretches from Senegal and The Gambia in the west, to Ethiopia in the east. Between 1996 and 1997 more than 25,000 people died from meningitis A infection in this region.
The population of 430 million people has been relatively spared in recent years, but the 47,925 cases reported from 1 January to 6 May 2007 bring the fear that a new epidemic wave may have begun.
The trial results have been announced by the Meningitis Vaccine Project (MVP), a partnership between the World Health Organisation and PATH, a nonprofit Seattle-based organisation that aims to help communities break long-standing cycles of poor health.
Along with the Centre for Vaccine Development (CVD) in Mali, scientists working at the MRC Laboratories in The Gambia helped to run the new group A vaccine trial under the leadership of Dr Brown Okoko (Principal Investigator) and Professor Richard Adegbola (Head of the Bacterial Diseases Programme). A total of 600 toddlers aged between 12 to 23 months participated in the research. The results show that it is not only safe but generates up to 20 times more protective antibody against meningitis A infection than the vaccine currently in use.
The high level of antibodies produced by children in response to the vaccine suggests that they will be protected from infection for several years. Blocking infection by meningitis bacteria in this way helps to generate the herd immunity that protects unvaccinated people in the children’s communities from meningitis.
The key to the new vaccine’s efficacy is its structure. It is a conjugate vaccine meaning that sugars from the meningitis bacterium are joined together with a protein designed to stimulate the immune system. When injected into the body, the combination of a bit of bacteria and a bit of protein prompts immune cells to produce antibodies that will protect against meningitis A infection.
Commenting on this recent success, Professor Tumani Corrah, Medical Research Council The Gambia’s Unit Director said:
MVP is collaborating with the vaccine production company Serum Institute of India Limited to make the new vaccine, it is expected that it will be sold at a price of 40 US cents a dose.