By Kemo Cham
Thirty years of efforts in the fight against Malaria - a major killer disease in Africa - maybe just about bearing fruits. This is according to reports last week that British drug manufacturer GlaxoSmithKline was seeking approval for its malaria vaccine.
The vaccine - RTS,S - will be the first of its kind for malaria or any parasitic disease, if approved for mass production and distribution.
It however will not be expected in circulation until around 2015. Nonetheless, there is every reason for celebration, especially in this part of the world - Sub-Saharan Africa - where malaria is endemic.
Malaria is perhaps the most popular parasitic disease, caused by a mosquito transmitted parasite, a protozoan called plasmodium. When a mosquito, usually the female Anopheles, bites its victim, it introduces the parasite into their system through its saliva.
The micro-organism then gets into the circulatory system and eventually the liver where the condition is such that it matures and multiplies. The effect and severity of the disease and its endgame is determined by the number of parasites in the body, which is why early diagnosis and treatment is important. Symptoms include fever and headache. In its worse cases malaria leads to coma and death.
According to the World Health Organization (WHO), the disease kills about 600,000 people yearly, mostly children.
There is hardly any certainty about the exact number of deaths due to this disease, but what many medical sources seem to agree on is that about 90% of the deaths caused by the disease to the disease occur in Africa.
In Sierra Leone, malaria is the number one killer disease, with children under five years, and pregnant women being the most vulnerable. According to the national Malaria Indicator Survey 2013, it is the leading cause of morbidity and mortality among children under aged 5, with a mortality of 38%. Malaria accounts for 50% of outpatient morbidity, and is responsible for 25% of death of all ages.
Weather conditions, coupled with environmental situations, vis-à-vis lack of clean vicinities around living quarters of majority of the population in our part of the world, constantly guarantee perfect breeding grounds for mosquitoes. This way, we can't think of a period when we can have a zero-malaria prevalence. The only thinkable thing is therefore prevention.
Clinical trials
A vaccine like RTS,S therefore represents a blessing, especially among the mainly poor rural folks who bear the brunt of the disease not just because of exposure to mosquitoes, but also because of their inability to access timely and affordable healthcare services.
At national levels, governments can save millions of dollars in malaria treatment which could go to other pressing health or related matters.
Various medical experts across the world have hailed the development
of RTS,S, whose production is said to have cost $350 million. The vaccine has been highly anticipated by the Global Alliance for Vaccine and Immunisation (GAVI) which spends billions of US Dollars on vaccines across the developing world.
Clinical trials for RTS,S were carried out in 13 research centres across Africa including Burkina Faso, Gabon, Ghana, Kenya, Malawi, Mozambique, Nigeria, and Tanzania. In the past, several projects to create a malaria vaccine ended up in futility because of the difficulty involved. This is specifically because parasitic organisms are said to be more complex than bacteria and viruses.
"It's very difficult to sustain natural immunity against a parasite - it's not well understood," said Sophie Biernaux, the woman who led the malaria vaccine project for GlaxoSmithKline.
Downside
RTS,S is being evaluated by the European Medicines Agency (EMA) in collaboration with WHO, even though it is intended exclusively for use outside the European Union.
The good news though is that the Path Malaria Vaccine Initiative, with financial support from the Bill and Melinda Gates Foundation, was instrumental in the development of the vaccine so that its manufacturers are promising to sell it at a cheaper prize. But for now, the focus is on its efficacy. RTS,S was tested under a controlled situation, administered on children who used bed nets and took anti-malaria drugs. The results, as indicated at various levels of the trial stages, were mixed.
In other words, this vaccine may only be effective when used alongside sleeping under bed nets and consumption of anti-malaria drugs.
Also, since it was designed for babies and children, its protection diminishes with time, prompting questions as to how long its effect would last, or how frequently it would have to be administered.
But again, the good news is that another trial of a different and more promising malaria vaccine is ongoing in Mali, Tanzania, Equatorial Guinea, US and Germany, under a US-based biotech company called Sanaria.
The vaccine, PfSPZ, is said to have demonstrated "complete" protection from malaria during initial trials. Its architect, Stephen Hoffman, an infectious-disease expert, says his project aims at total elimination of the parasite, unlike the RTS,S. But Sanaria is not expected to file for approval until 2017.
Another 'but' with PfSPZ is that it must be stored in super-cold liquid nitrogen, which will prove a difficult thing in Africa where it is going to be needed mostly.
(C) Politico 01/08/14
