One-fifth dose of a commonly used vaccine against meningitis may be as effective as a full dose, according to a study published December 1 in the journal PLoS Neglected Tropical Diseases.
Philippe Guerin is director of Epicenter, the research branch of the nonprofit Doctors Without Borders. He says the finding is critical in the so-called Meningitis Belt across Sub-Saharan Africa, where outbreaks occur nearly every year.
Meningitis is an infection of the lining of the brain and spinal cord. The World Health Organization reported 40,000 cases in the region in 2006, resulting in approximately 4,000 deaths.
"If you take even a conservative approach, that you believe that the fractional dose does not protect as well as the licensed vaccine, we believe that it would allow protection of much more people than using only one dose for one vaccine," says Guerin.
The scientists gave various fractions of the full dose to 750 healthy Ugandans between the ages of 2 and 19, the most vulnerable age for the disease.
Guerin says he was not surprised that a fraction of a dose would be as effective as the licensed full dosage.
"There [has been] much more research on dose findings on the most appropriate dosage to induce the best immune response," he says.
Guerin says the results can help public health officials better manage the disease, especially considering the chronic shortage of vaccine supplies in Africa.
"This will be done only in a scenario of a public health emergency