Radical boost for malaria fight

Malaria, a serious health problem in Tanzania, can be eradicated in just three years, according to a leading expert on the prevention and treatment of the disease.

Prof Li Guoqiao recently told a delegation of Tanzanian journalists in the southern Chinese city of Guangzhou that the disease could be wiped out in Tanzania within two to three years through the proper implementation of the Fast Elimination of Malaria by Source Eradication (Femse) strategy.

Femse is the brainchild of Prof Li and his team of experts from the Guangzhou University of Chinese Medicine (GUCM) and entails mass drug administration (MDA) with artemisinin-based combination therapies (ACTs) to eliminate malaria.

Speaking at GUCM, Prof Li said Femse had registered resounding success in pilot projects in Cambodia and the Comoros, adding that the success could be replicated in Tanzania, where malaria is still endemic.

“Through Femse, malaria prevalence has been cut from 60 per cent to under 5 per cent in Cambodia. I’m also happy to report that no malaria case was reported in the Comoros in 2014. If the strategy has succeeded in Cambodia and the Comoros, there is no reason why it shouldn’t work in Tanzania,” he said in his presentation that was also attended by senior GUCM academics.

Prof Li, who is widely recognised as the father of artemisinin-based anti-malarial drugs, said what made Femse effective was the fact that the strategy focuses on eliminating the malaria parasite within the human population in a specific area instead of attempting the “impossible” task of eradicating the vector (mosquitoes), particularly in tropical areas.

“It is impossible to eradicate mosquitoes…if you eradicate the malaria parasite within humans, there will be no parasites for mosquitoes to transmit and this means there will be no malaria. This is what Femse is all about,” he said.

Prof Li said it cost an average of $9 to $10 per person to implement Femse, but added that although the cost might seem high, it was much cheaper than other methods of eradicating malaria. Going by Prof Li’s estimate, it would cost about $500 million (Sh1 trillion) to implement Femse in Tanzania.

The respected researcher admitted that funding was a major impediment to implementing the Femse strategy in developing countries where malaria was prevalent, and said GUCM was planning to initiate talks with the Chinese government and the Bill & Melinda Gates Foundation to find a way around the hurdle.

Asked whether Tanzania could eradicate malaria through vaccination, Prof Li said vaccine trials were still at the clinical stage, but added that even if they were a success, wiping out the disease through vaccination would initially be prohibitively expensive.

According to an article in The Economist, Prof Li’s Femse approach is to attack not the mosquito, but the disease-causing parasite itself. This parasite’s life cycle alternates between its insect host (the mosquito) and its vertebrate one (human beings). Crucially, as far as is known, humans are its only vertebrate host. Deny it them and it will, perforce, wither away—an approach that worked for the smallpox virus, which had a similarly picky appetite. In the case of smallpox, a vaccine was used to make humans hostile territory for the pathogen. Since there is no vaccine against malaria, Prof Li is instead using drugs.

The drugs in question are artemisinin and a second antimalarial called piperaquine—a combination made and sold under the brand name “Artequick” by Artepharm, a firm based in Guangdong which Prof Li helped found. Adding piperaquine to the mix reduces the risk of a strain of parasite resistant to artemisinin evolving, because the chance that an individual parasite will be immune to both forms of attack is negligible. (A similar approach is employed in the combination therapies used to treat HIV infection.)

To deny the parasites their human hosts long enough to exterminate them in a given area, the researchers administer three doses of Artequick, spaced a month apart. To add extra power, the first dose is accompanied by a third drug, primaquine.

In Tanzania, malaria kills an estimated 60,000 people annually, 80 per cent of whom are children under five years of age.

According to the World Health Organisation, an estimated 3.3 billion people are at risk of malaria, of whom 1.2 billion are at high risk. In high-risk areas, more than one malaria case occurs per 1,000 population.

There were an estimated 198 million cases of malaria worldwide (range 124–283 million) in 2013, and an estimated 584,000 deaths (range 367,000–755,000). Ninety per cent of all malaria deaths occur in Africa.

In 2013, an estimated 437,000 African children died before their fifth birthday due to malaria. Globally, the disease caused an estimated 453,000 under-five deaths in 2013.

Between 2000 and 2013, an expansion of malaria interventions helped to reduce malaria incidence by 30 per cent globally, and by 34 per cent in Africa.

During the same period, malaria mortality rates decreased by an estimated 47 per cent worldwide and by 54 per cent in Africa. In the under-five age group, mortality rates have declined by 53 per cent globally, and by 58 per cent in Africa.

New analysis reveals that the prevalence of malaria parasite infection (including both symptomatic and asymptomatic infections) has decreased significantly in Africa since 2000. The number of people infected fell from 173 million in 2000 to 128 million in 2013 – a reduction of 26 per cent. This has occurred despite a 43 per cent increase in the African population living in malaria transmission areas.