* Meningitis killed more than 1,100 in Nigeria and Niger
* One third of world emergency vaccine stockpile dispatched
* Deadly disease spreads through kisses, sneezes, coughs
(Adds WHO quotes in paragraphs 4 and 12; background)
By Laura MacInnis
GENEVA, March 27 (Reuters) - One third of the world's stockpiled meningitis vaccine doses have been dispatched to West Africa where an outbreak has killed more than 1,100 people since January, the World Health Organisation (WHO) said on Friday.
Meningitis is an infection of the thin lining that surrounds the brain and spinal cord. Infection rates in Africa tend to rise during the dry and hot period from January to May.
So far this year, the WHO said nearly 25,000 suspect cases have been reported across the "meningitis belt" that stretches from Senegal to Ethiopia, with 85 percent of those concentrated in Niger and Nigeria. WHO says 300 million people in that area are at risk of the disease every year.
"The current epidemic is the biggest these countries have faced in the past five years," said Fadela Chaib, a spokeswoman for the U.N. agency.
In response, more than 4 million meningitis vaccine doses -- one third of the world's emergency stockpile of 13 million doses -- have been released to boost immunity levels in those two countries, she told a news briefing in Geneva.
In the past week alone, 171 people have died in Nigeria and about 30 in Niger from meningitis, which spreads mainly through kisses, sneezes, coughs, and in close living quarters, especially when people share cups, forks, and spoons.
"We will need a large amount of vaccines," Chaib said. "The stockpile of vaccines is a limited one."
The largest recorded meningitis outbreak in the African high-risk zone, where like polio the disease is endemic, occurred in 1996-1997 when an estimated 100,000 people were infected in Nigeria and 50,000 in Niger.
Symptoms include a stiff neck, fever, sensitivity to light, confusion, headaches and vomiting. About 5 to 10 percent of patients die within 24-48 hours of the onset of symptoms, even with quick diagnosis and therapy. Up to 20 percent of people who survive infection with bacterial meningitis suffer brain damage, hearing loss, or learning disability.
"During the dry season...because of dust winds and upper respiratory tract infections due to cold nights, the local immunity of the pharynx is diminished, increasing the risk of meningitis," a WHO factsheet said. Population movements to pilgrimages and large markets also contribute to epidemics.
The Global Alliance for Vaccines and Immunisation last year approved millions of dollars in funding to buy more meningitis vaccines for use during epidemics in Africa.
Those purchases should start soon, said a spokesman for the Geneva-based GAVI, which is backed by the Bill & Melinda Gates Foundation and whose financing arm raises money for vaccine programmes through the sale of bonds in capital markets.
Meningitis vaccines are made by major pharmaceutical companies including Novartis NOVN.VX and Wyeth WYE.N.
Editing by Mark Trevelyan