DAKAR, 14 October 2010 (IRIN) - The emergence of a new meningitis vaccine, rather than a large-scale outbreak of the disease, has prompted the current vaccination drive across West Africa. Health officials say the vaccine marks a "revolution" in preventing the highly contagious and fatal disease.

Health workers in Burkina Faso, Mali and Niger - the three countries selected for introduction of the vaccine - are preparing for country-wide campaigns set for December, having just completed a limited pilot phase.

"This vaccine, which targets the bacterium [meningococcus A] most frequently causing epidemics, is about preventing epidemics, not waiting, then reacting," Mamoudou Harouna Djingarey of the Meningitis Vaccine Project (MVP) in Burkina Faso told IRIN. Up to now countries in the region vaccinated communities only once an outbreak had started.

Routine vaccinations with polysaccharide vaccine - used hitherto in the region - were not viable because the vaccine protects for only two to three years, and is not effective in children under two.

The just-launched meningococcal A conjugate vaccine - developed by Serum Institute of India under a partnership by the World Health Organization (WHO) and the international NGO PATH - provides protection for 10 years.

"To achieve a vaccine four times stronger than existing ones, at 200 CFA francs per dose, [40 US cents, compared to about US$1 for past vaccines] and which will protect for 10 years, is truly a revolution for public health," Djingarey said.

"This will allow countries to avoid huge meningitis A epidemics and save their resources for other public health needs." Health experts note that the infection will circulate less with the new vaccine, thereby protecting even non-vaccinated populations from the disease, one of the region's greatest public health burdens.

The so-called "meningitis belt" of sub-Saharan Africa, from Senegal to Ethiopia, has the world's highest rates of meningitis, with epidemics generally coming in the dry season from December to June. In 2009, 14 African countries reported 88,199 suspected cases with at least 4,050 deaths, according to WHO.

This year the region to date is seeing lower numbers but more patients are dying, according to MVP.

Different strains

While meningitis A is the most common cause of epidemics, other strains emerge some years as well, such as W135 in Chad in 2009 and strain X in Burkina Faso earlier this year.

Countries still must be ready to react with vaccination campaigns for other strains of meningitis and in this sense preparedness remains a challenge, health experts say.

But meningitis A has by far been the biggest problem, said Marie-Pierre Preziosi, medical officer with the product research and development team in WHO's immunization, vaccines and biologicals department.

"Meningitis A is responsible for nearly all of the epidemics in the past century - so while there are other strains that emerge... there has never been another strain that has been so prominent," she told IRIN.

Funding gaps

Funding constraints have threatened meningitis vaccine supplies in the past and money is needed to fully roll out the new vaccine, Preziosi said. "There are sufficient doses available of the meningococcal A conjugate vaccine to start the nationwide campaigns in Burkina Faso, Mali and Niger, but there is a funding gap of $475 million to complete these drives and to roll out in the other meningitis belt countries."

Burkina Faso, Mali and Niger were selected as the first countries to introduce the vaccine due primarily to their high prevalence of meningitis as well as their capacity to carry out mass vaccination campaigns.