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June 15 (Bloomberg) -- A vaccine developed by Serum Institute of India Ltd. was better at protecting people from the predominant strain of meningitis in sub-Saharan Africa than older products made by companies including GlaxoSmithKline Plc, researchers said.
About 600 children under two years old were given the vaccines and their immunity levels tested four weeks and 10 months after the inoculation. More than 96 percent of those who received Serum’s MenAfriVac had high levels of antibodies in their blood after four weeks, compared to 64 percent in the group that got Glaxo’s Mencevax Acwy, scientists wrote in a paper published in the New England Journal of Medicine today.
The vaccine could prevent about 150,000 deaths by 2020, lead author Marie-Pierre Preziosi said in a telephone interview yesterday. Since 1988, more than a million people in Africa have been infected by the disease, which causes mental retardation, permanent deafness and can be fatal within hours if untreated, according to the World Health Organization.
“For more than a century, these African countries have been suffering because of this huge and devastating epidemic,” Preziosi, who heads the unit responsible for clinical development of a meningitis vaccine at the WHO, said from her Geneva office. “We now have a tool that has the potential to eliminate meningitis epidemics from Africa.”
In 2010, Burkina Faso became the first nation to offer the vaccine, which costs 50 cents a dose and was developed with funding from the Bill & Melinda Gates Foundation, to all citizens below 30. There have been four confirmed cases this year, the lowest ever incidence in the nation’s history, Preziosi said. Last year there were 66 confirmed cases of meningitis caused by the A strain, which is responsible for nearly 85 percent of cases in Africa, she said.
The first study referred to in the paper took place between 2006 and 2007 and data from toddlers in Mali and Gambia was examined. Most of the participants received a primary shot and a booster dose 10 months later. Blood tests taken before and after inoculations assessed the concentration of antibodies that protect against disease-causing germs.
The second study was of 900 people from two to 29 years of age and they received a single dose. Antibody levels were tested four weeks later.
A region in sub-Saharan Africa comprising 25 countries from Senegal in the west to Ethiopia in the east is called the “meningitis belt” because more than 90 percent of all cases occur there, according to the Geneva-based WHO. Nearly 25,000 people died and 10 times as many were infected in the worst-ever epidemic in 1996 and 1997.
Meningococcal disease is an infection of the membrane surrounding the brain and spine. It is transmitted when a passerby inhales germs released when an infected person coughs or sneezes.
Older vaccines including Mencevax and Sanofi’s Menomune belong to a category of inoculants called polysaccharide vaccines, which contain a portion of the outer shell of the disease-causing bacterium. Immunity is developed when the body produces antibodies after being exposed to a small chunk of the pathogen’s external shell which is made of sugars that are also known as polysaccharides.
Both these vaccines confer protection from all four strains of the bacteria, A, C, Y and W-135, and are consequently more expensive, Prasad Kulkarni, additional medical director at Serum, said in a telephone interview from Pune in western India yesterday.
Serum’s product is a so-called conjugate, in which the polysaccharide shell is combined with a protein carrier, a process that confers immunity from the disease for up to 20 years, Kulkarni said. It only protects against the most prevalent A strain of the bacterium.
About 20 million people in sub-Saharan Africa have received the Serum vaccine to date. Another 45 million people from Mali, Niger, and three other countries will be inoculated by December, WHO’s Preziosi said.
--Editors: Alan Soughley, Phil Serafino
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