Tag: Meningitis

Animal Research Moves Multi-Strain Meningitis Vaccine Efforts Forward

Researchers at the University of Surrey recently announced they had created a strain of meningitis B that cannot cause the often-deadly symptoms of the disease and thus could eventually lead to the development of a vaccine against the disease.

Currently, there are viable vaccines for both A and C strains of meningitis but not the B strain. Moreover meningitis is a major problem in developing countries because vaccines for the separate A and C strains of the disease are relatively expensive.

The new finding could kill both problems at once — after injecting mice with the strain of meningitis B, they found that the immune system of the animals created antibodies for all three major strains of the disease. A single vaccine that could provide immunity to all three strains would be a major development in efforts to reduce meningitis cases around the world.

The researchers who announced this discovery emphasized that their genetically engineered strain of meningitis B is not a vaccine yet. Dr. Johnjoe McFadden, lead researcher on the project, told BBC News Online,

At the moment, it isn’t a vaccine. What we need to do is identify the proteins in this strain that cause this cross reaction. We hope we will be able to complete this work within three years. However, we need additional funding if we are to press ahead with this work. At the moment, we don’t have funding to take this research forward.

This advance was made possible thanks to the sequencing of N. meningitidis in 2000.

Sources:

Improved meningitis vaccine ready ‘within a decade’. The Guardian, Stewart Maclean, January 5, 2004

Hope For New Meningitis Vaccine. Medica.De, January 5, 2004.

Vaccine ‘could beat meningitis’. The BBC, January 6, 2004.

New Meningitis Vaccine Could Save Lives in Developing World

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.