April 25: World malaria day #endmalaria

April 25: World malaria day #endmalaria

Malaria remains both a major cause and a consequence of global poverty and inequity: its burden is greatest in the least developed areas and among the poorest members of society. Many of those most vulnerable – especially young children and pregnant women – are still not able to access the life-saving prevention, diagnosis and treatment they so urgently need.

Today is world malaria day – having spent a good part of my adult life studying malaria – I am always bursting to talk endlessly about it. However, I will restrict myself and talk about the issue of malaria eradication in two short blogs.

Eradication of malaria means totally getting rid of the malaria parasite from the world.

Since 2007, Bill and Melinda Gates foundation put malaria eradication on the global agenda, donating a billion US dollars to a variety of malaria programs, including the development of the RTS, S malaria vaccine.

There was a lot of hope that a malaria vaccine would be part of the core tools for malaria control but the results, from the most advanced of the malaria vaccines, RTS, S must be a disappointment for many that hoped it would be an essential tool in the malaria eradication kit. I wrote about those results when they were released in 2015….

The other tools currently available for malaria eradication include the use of insecticide-treated bednets, indoor house spraying, use of artemesinin combinations for treating malaria, rapid diagnostic tests and intermittent preventative treatments for pregnant women and infants.

To understand the malaria eradication situation, we would need to think about the only disease that humanity has ever managed to eradicate – Smallpox. Keep in mind that eradication means the complete disappearance of the disease-causing agent on the face of the earth. The Smallpox virus is now only currently held in a few labs in the world and only the folly of humanity would return the virus to haunt us.

Smallpox was eliminated using a vaccine that had a protective efficacy of 99% – aggressive quarantine and vaccination were enough to eradicate smallpox from the world.

The world is on the verge of polio eradication with a vaccine that reduces wild-type polio by 95%. Polio is currently endemic in 2 countries: Pakistan and Afghanistan. Africa and India have declared polio-free a few years ago. Even though polio is now restricted to just a few countries, with less than a hundred cases a year, eradication is taking longer than expected.

None of the tools for malaria eradication has an efficacy anywhere close to the one for the diseases on the eradication radar. On the other hand, over half of the world’s population is at risk of malaria infection. It is estimated that there are over 200 million cases of malaria illness and about 400,000 deaths every year in Sub-Saharan Africa.

The African Leaders Malaria Alliance (ALMA) is geared to the goal of eliminating malaria from the continent in 2030. Note that the goal is the elimination of disease not the eradication of the parasite.

It is expected that as each country eliminates malaria disease, in a few decades, the world will eradicate the malaria parasite. The ALMA malaria elimination scorecard shows how all 49 member African countries are fairing towards this desired goal. Only Algeria and Cape Verde are close to eliminating malaria.

Read here: ALMA 2030

Malaria vaccine implementation starts next year


On (24th April), The World Health Organization Regional Office for Africa (WHO/AFRO) announced that Ghana, Kenya, and Malawi will take part in a WHO-coordinated pilot implementation programme that will make the world’s first malaria vaccine available in selected areas, beginning in 2018.

Ghana, Kenya and Malawi to take part in WHO malaria vaccine pilot

Ghana, Kenya and Malawi will select the areas with highest malaria burden to be involved in a large RTT, S rollout. It is estimated that over 750,000 children aged 5- 17 months will be vaccinated starting next year (2018).

I was confused when I heard in the news that children 5-17 months will be vaccinated – and I thought I had heard it wrong — after all, if you want to give 4 doses of a vaccine, you would want to do this through the usual routine vaccinations.

I contacted experts in the field and was assured that this is the case. The implementation of the malaria vaccine, RTS, S is aimed at children 5 – 17 months.

The reasoning behind giving the vaccinations in the 5-17 month period is that during the clinical trials, using the routine schedule at 6,10, 14 weeks, the protective effect of the vaccine was low and also that protection did not last long.

The vaccines that most people are used to polio, measles, tetanus – prevent over 90% of the disease they protect against – this protection lasts a lifetime. The malaria vaccine RTS, S in trial conditions has been shown to have an efficacy of 26-36% and this efficacy declined very quickly….

Decline in protection using malaria vaccine

Children who were vaccinated with RTS, S malaria vaccine actually had more episodes of malaria when they got older because they had not acquired natural immunity compared to their unvaccinated agemates. It appeared that vaccinating early may not have the desired effect. It, therefore, makes more sense to vaccinate older children.

Because of the waning of the protection, the children would also receive a booster vaccination.

This means that next year, in areas where malaria levels are high in Kenya, Ghana and Malawi, children will be having the usual routine vaccinations at 6,10,14 weeks of age for pentavalent, pneumococcal vaccine, polio vaccine and then start another whole lot of vaccinations for malaria at month 5, they will receive 3 vaccines a month apart and then get a booster dose after a year or so of these initial vaccinations. Remember they still have their measles vaccination at 9 months.

This is really not going to be easy.

I would have expected that a malaria vaccine would only be rolled out if it fitted into the routine vaccination programs and was at least protective throughout childhood. Researchers have shown that in areas with the very highest malaria transmission, the peak of severe malaria episodes was 3-5months from data collected from the Lake Victoria region of Kenya in the 1990’s – an area where the implementation study will most certainly be conducted...

Malaria peaks before 5th month in high transmission areas

Vaccinating older infants in this region will, therefore, have missed out on a period of greatest risk – malaria episodes will be prevented – yes – but not when it was most needed.

I am surprised at the decision by the World Health Organization (WHO) to implement a whole new system of vaccinations on top of a system that is just about trying to do its job right. However, it would be foolish to say that it should not be done – everything needs to be thrown at malaria – to see the end of it. But the people on the ground really need to understand the issues involved.

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