By Tania Rabesandratana
Just a month after Paraguay got its malaria-free certificate from the World Health Organization, a new book takes stock of the prospects for eliminating the disease around the world.
SciDev.Net spoke with Sylvie Manguin, a researcher at the Institute of Research for Development in Montpellier, France, about the hurdles on the road towards that goal.
Along with Vas Dev, who recently retired from India’s National Institute of Malaria Research, Manguin edited the book Towards Malaria Elimination – A Leap Forward, with contributions about major challenges, progress in different countries, as well as vaccines and other approaches to curb malaria.
The book is due to be released this week (18 July) by the open access publisher IntechOpen. Each of the 17 chapters, authored by scientists from five continents, is available to download for free by anyone in the world.
Paraguay got certified as malaria-free by the World Health Organization (WHO) last month. What can we learn from this success?
The WHO gives elimination certifications after three successive years without malaria cases, like in Paraguay now and Sri Lanka [in September 2016]. China does not have the certification yet but probably will within two years; in 2017 there was no malaria case in China. That’s a very interesting aspect that we developed in one of the book’s chapters: China has a very strict and pyramidal organisation to control malaria, and I think it’s really the way to go. You have a central, main office and health centres [across the country] where people report cases as soon as they occur. It’s not only something that we discuss in the office; people have to react very quickly in the field.
The involvement of people in villages is very important to eliminate malaria. They have to know how they get sick; that the mosquito is a key element in the cycle of malaria; to recognise if someone has malaria [and how symptoms differ from] dengue or the flu; to ask sick people to get treated. Besides this, the head of the community has to be really involved and pass on information to implement vector control. Many NGOs provide impregnated bednets, but if people don’t know why they should use them, they won’t. They will keep them in their plastic bags or use them to catch fish.
Were there any surprises in the book’s contributions?
I was surprised by [the] situation in Venezuela. Because of political instability, the whole public health system has been destroyed, so the number of malaria cases has increased by 365 per cent between 2010 and 2015. Venezuela was at the elimination stage a few years ago, but malaria is now booming there; they have deaths from malaria. I knew malaria would come back, but I didn’t know it would [increase] so quickly.
The Sustainable Development Goals aim to end the malaria epidemics by 2030. How realistic is that goal?
If people from Southeast Asia get together and develop an international strategy, they will be on the right track to eliminate malaria [in the region]. It’s really a question of political will to work together. India is well organised and also has to work with neighbouring countries, but I think they can reach malaria elimination in the next two decades. In Latin America, elimination is also totally possible with sustained effort in the coming years. We have to keep pressure on the disease; even after WHO certification, governments have to keep strategies in place to control cases.
But I don’t know if malaria can be eliminated in Sub-Saharan Africa, where more than 99 per cent of cases are due to Plasmodium falciparum. That’s the deadly species of the parasite: if you don’t get treatment against it, you die. [In 2016], 91 per cent of deaths due to malaria occurred in Sub-Saharan Africa, compared to 6 per cent in Southeast Asia.
What is the biggest obstacle to eliminating malaria?
One of the obstacles is the drug resistance of the parasite Plasmodium. Nowadays, sick people take a medication called Artemisinin Combination Therapy (ACT). Now [resistant parasites are found] in Southeast Asia, starting in Cambodia, now expanding to Vietnam, Laos, Thailand and moving towards Myanmar. The big threat now is that ACT resistance is moving to India. [If this happens,] there is a high chance that [migrant] African workers get infected by a resistant parasite in India and go back to Africa with it. If ACT resistance goes to Africa, it will be a major problem. There will be no more medication to treat people and that means the number of malaria deaths will jump up.
Mosquitoes also become resistant to insecticides, so there’s a double resistance in the malaria [transmission] cycle. My lab studies plants that people use on a regular basis to repel mosquitoes; we found interesting molecules that could be put on the market after testing. If we could have a new repellent that is safe for the environment, this would give us new ways to control malaria.
This Q&A was edited for brevity and clarity.