Had to share this guys...must read for parents.
- Malaria vaccine once thought promising is turning out to be a disappointment, with a new study showing it is only about 30 percent effective at protecting infants from the killer disease.
Dr. Jennifer Cohn, a medical coordinator at Doctors Without Borders, described the vaccine's protection levels as "unacceptably low." She was not linked to the study.
Scientists
have been working for decades to develop a malaria vaccine, a
complicated endeavor since the disease is caused by five different
species of parasites. There has never been an effective vaccine against a
parasite. Worldwide, there are several dozen malaria vaccine candidates
being researched.In 2006, a group of experts led by the World Health Organization said a malaria vaccine should cut the risk of severe disease and death by at least half and should last longer than one year. Malaria is spread by mosquitoes and kills more than 650,000 people every year, mostly young children and pregnant women in Africa. Without a vaccine, officials have focused on distributing insecticide-treated bed nets, spraying homes with pesticides and ensuring access to good medicines.
In the new study, scientists found babies who got three doses of the vaccine had about 30 percent fewer cases of malaria than those who didn't get immunized. The research included more than 6,500 infants in Africa. Experts also found the vaccine reduced the amount of severe malaria by about 26 percent, up to 14 months after the babies were immunized.
Scientists said they needed to analyze the data further to understand why the vaccine may be working differently in different regions. For example, babies born in areas with high levels of malaria might inherit some antibodies from their mothers which could interfere with any vaccination.
"Maybe
we should be thinking of a first-generation vaccine that is targeted
only for certain children," said Dr. Salim Abdulla of the Ifakara Health
Institute in Tanzania, one of the study investigators.
Results were presented at a conference in South Africa
on Friday and released online by the New England Journal of Medicine.
The study is scheduled to continue until 2014 and is being paid for by
GlaxoSmithKline and the PATH Malaria Vaccine Initiative.
"The
results look bad now, but they will probably be worse later," said
Adrian Hill of Oxford University, who is developing a competing malaria
vaccine. He noted the study showed the Glaxo vaccine lost its potency
after several months. Hill said the vaccine might be a hard sell,
compared to other vaccines like those for meningitis and pneumococcal
disease — which are both effective and cheap.
"If
it turns out to have a clear 30 percent efficacy, it is probably not
worth it to implement this in Africa on a large scale," said Genton
Blaise, a malaria expert at the Swiss Tropical and Public Health
Institute in Basel, who also sits on a WHO advisory board.
Eleanor
Riley of the London School of Hygiene and Tropical Medicine, said the
vaccine might be useful if used together with other strategies, like bed
nets. She was involved in an earlier study of the vaccine and had hoped
for better results. "We're all a bit frustrated that it has proven so
hard to make a malaria vaccine," she said. "The question is how much
money are the funders willing to keep throwing at it."
Glaxo first developed the vaccine in 1987 and has invested $300 million in it so far.
WHO
said it couldn't comment on the incomplete results and would wait until
the trial was finished before drawing any conclusions.
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