, NAIROBI, Kenya, Nov 3 – Health Experts attending the Pan African Malaria Conference in Nairobi have said a vaccine could be made available to African governments by the year 2012.
Dr Sirima Sodiomon of the National Centre for Research and Malaria Training in Burkina Faso said on Tuesday that the vaccine targeted the African continent because it was the most prone to the Malaria epidemic.
He said the efficacy rate of the vaccine was expected to be about 30-50 percent.
“We need to continue with the research and may be the second generation vaccine which may come up in five to six years may have a higher efficacy rate of about 80-90 percent,” Dr Sodiomon said.
He said researchers were now on the third phase of trials which was the most crucial and involved large number of people for the clinical tests and this would have 16,000 children, 5,000 of whom would be from Kenya.
“Vaccines are one of the best ways to protect against any disease but currently we don’t have any efficacy vaccine but at least we hope to have this one which will protect from 30-50 percent and then compliment it with other strategies like bed nets,” the medic said.
Dr Patricia Njuguna, Principal Investigator and Co-Chair of the Clinical Trials Partnership Committee said Kenya would have three trial sites all under the Kenya Medical Research Institute (KEMRI), one in Kilifi and the other two in Western Kenya.
She said the trials would be done in seven African countries to children of two age categories-five to 17 months and six to 12 weeks.
“So far we have been able to show that the vaccine is safe in both phase one and two trials,” Dr Njuguna said.
“The only concerns would be things like fever which are also seen with other vaccines but we will still keep an eye for any other concerns that could come up,” she added.
Dr Wilfred Mbacham of the University of Yaoundé in Cameroon however expressed fears that African governments may not be well prepared for massive deployment of the vaccine.
“They need to train their researchers to understand who can advice them on exactly what the regulatory issues are and safety issues. I have not seen any country where the entire population is uniform, countries need to understand the epidemiology of the disease to know exactly when people are going to respond better to the vaccine and when they are not going to respond,” Dr Mbacham said.
He said countries had different epidemiologies in terms of transmission patterns.
“If a child is going to have nine episodes of malaria in a year like what happens in Tororo, Uganda, how many times should you give the vaccines?” he posed.
“Researchers in those countries need to know because if you give a single shot vaccine and you think the child is going to be protected, and the child is over infected and has repeated episodes, then a single dose may not be what is necessary,” he added.
He said countries also needed to know how to handle from the airport to storage in medical facilities and its distribution.
“We need to understand the shelf life, if going through this chain something is interrupted, will it still be effective, do we need to bring in a new vaccine, so there are all these logistics difficulties that countries need to consider,” Dr Mbacham said.
The medic also said rapid diagnostic tests should be subsidised to make them easily available to avoid people self medicating without first testing.
He said subsidising the rapid diagnostic tests and the recommended Artemisinin based combination therapy would reduce counterfeits from the market.
“The challenge is finding out how many times you would be able to test and find positive to malaria because if you test and find it negative and the next time you don’t have a RDT then the tendency is that you may treat any of the fever directly at home.
If you base the argument that 30 percent of the population that have a fever in Africa are actually positive for malaria, then for every one dose of treatment we need to put in four diagnostic tests
He said currently RDT’s cost about $2 but if they were subsidised, they would sell at less than 50 cents.