The 25th of April marks World Malaria Day and, this year adopts the theme: “Ready to beat Malaria” 1. World Malaria Day was established with the objective of raising awareness for one of the oldest diseases 1; an epidemic that has shaped human history and continues to prevail today with over 200 million cases and 445,000 deaths reported globally in 2016, and half of the world’s population are at risk of becoming sick with malaria 5.
Malaria is an acute febrile disease caused by the family of Plasmodium parasites and is transmitted through the infected female of Anopheles mosquitoes 2. The disease is most prominent in vulnerable communities, such as those where access to prevention and treatment options are limited, and is disproportionately felt by children under the age of five years old. The greatest burden of disease is observed across the African continent, with an important focus on South America and Southeast Asia 3.
Despite these big numbers, we have never been in such upfront position to beat malaria. However, since the early 2000s, there has been a significant decrease in both cases and mortality rates. This is largely owing to insecticidal nets having been mass distributed as a primary preventative tool 3. Unfortunately, vaccines to tackle malaria are still far from 100% efficacy, but major advancements have been made in the area over the past 20 years. Currently, the first malaria vaccine for P. falciparum 5 is being piloted in endemic countries. Further, vaccine research for P. vivax and P. ovale has increased in recent years 4. Preventive therapies, such as ‘intermittent preventive treatment in pregnancy’ or “seasonal chemoprevention”, are well-established strategies and could further contribute to reducing the number of cases and deaths 3,5. In addition to these efforts, the Global Technical Strategy (GTS) was launched in 2015 to develop a roadmap to achieve a minimum reduction of 90% in mortality and incidence and, subsequently, eliminate malaria in at least 35 countries by 2030 5.
There are still challenges that have to be addressed to maintain the progress made until now, otherwise, malaria will strike back stronger than ever. Some of the challenges are:
- Reemergence and strong heterogeneities in the malaria burden. This is evidenced by 15 of the 91 countries with indigenous malaria comprising 80% of the disease burden. In the last two years, incidence has increased mainly in South America 3.
- Resistance to drugs is one of the main threats to global health. While chloroquine has been recognized decades ago, recently, the Greater Mekong subregion in South East Asia has a confirmed multidrug resistance for malaria since 2008 6. We have to expect the emergence of resistance in other parts of the world if new drugs are not available soon.
- Resistance to insecticides has increased, and therefore, decreased the efficacy of the most used class of insecticides, pyrethroids, that are essential for vector control and key in case reduction 7.
- Climate change is anticipated to impact the dynamics and distribution of malaria transmission 5. Developing a proactive approach to these changes is critical and be a key strategy to prevent a huge increase in the incidence.
- Investment remains stable since 2010 but to reach the milestones proposed in the GTS we have to at least double the current investment by 2020 3,5.
Research has always been a keystone in the fight against malaria and if we want to reach the milestone of malaria elimination or even eradication we have to target the areas where there is a gap in knowledge. As such, this is also an open call to those interested in science and who care about one of today’s biggest global health threats. The Malaria Eradication Research Agenda (malERA) launched in 2017 listed the priority research areas 8 that I believe global health professionals should invest their careers in:
- Basic science and enabling technologies;
- Insecticide and drug resistance;
- Characterizing the reservoir and measuring transmission;
- Diagnostics, drugs, vaccines, and vector control;
- Combination interventions and modeling;
- Health systems and policy research.
Finally, we must not forget the history of malaria if we want to succeed in malaria elimination. Malaria was among the first disease-specific campaigns to emerge with the Global Malaria Eradication Program (GMEP) having launched in 1955 9. In spite of remarkable reductions being made in the geographical regions affected by the disease, the program failed for several reasons that we should be aware in applying the new Global Technical Strategy for 2015 – 2030.Perhaps most critical is that we not relax research and prevention efforts. Following the GMEP implementation, relying mostly on DDT pesticide, research in malaria was abandoned, vertical programs were set and population needs were not taken into account 9. Besides, the “global” program “forgot” the African continent, due to the impossibility to eliminate malaria from there since there was a lack of infrastructure and governance. Therefore, programs should develop flexible strategies, continue investing in research and engaging with the local communities in developing new strategies that are more compatible with local communities, context, and epidemiology. It is absolutely essential that we involve communities in every step of the eradication effort in order to achieve a malaria-free world 9.
- WHO (2018). World Malaria Day. Geneva: World Health Organization. Available from: <http://www.who.int/campaigns/malaria-day/2018/en/>.
- WHO (2018). Malaria. Geneva: World Health Organization. Available from: <http://www.who.int/mediacentre/factsheets/fs094/en/>.
- WHO (2017). World Malaria Report. Geneva: World Health Organization. Available from: <http://apps.who.int/iris/bitstream/handle/10665/259492/9789241565523-eng.pdf;jsessionid=B9F3F996C9D5E9A6B2433592F4AEBEBC?sequence=1>.
- The malERA Refresh Consultative Panel on Tools for Malaria Elimination (2017). malERA: An updated research agenda for diagnostics, drugs, vaccines, and vector control in malaria elimination and eradication. PLoS Medicine, Nov 30;14(11). Available from: <http://dx.plos.org/10.1371/journal.pmed.1002455>.
- WHO (2015). Global technical strategy for malaria 2016-2030. Geneva: World Health Organization. Available from: <http://apps.who.int/iris/bitstream/handle/10665/176712/9789241564991_eng.pdf?sequence=1>.
- Imwong, M., Hien, T.T., Thuy-Nhien, N.T., Dondorp, A.M., White, N.J. (2017). Spread of a single multidrug-resistant malaria parasite lineage (PfPailin) to Vietnam. The Lancet Infectious Diseases, 17(10):1022–3. Available from:<http://dx.doi.org/10.1016/S1473-3099(17)30524-8>.
- Hemingway, J., Ranson, H., Magill, A., Kolaczinski, J., Fornadel, C., Gimnig, J. et al. (2016). Averting a malaria disaster: will insecticide resistance derail malaria control? The Lancet, 387(10029):1785–8. Available from: <https://www.ncbi.nlm.nih.gov/pubmed/26880124>.
- Rabinovich, R.N., Drakeley, C., Djimde, A.A., Hall, B.F., Hay, S.I., Hemingway, J. et al. (2017). malERA: An updated research agenda for malaria elimination and eradication. PLoS Medicine, 14(11): e1002456. Available from: <https://doi.org/10.1371/journal.pmed.1002456>.
- Nájera, J.A., González-Silva, M., Alonso, P.L. (2011). Some lessons for the future from the Global Malaria Eradication Programme (1955-1969). PLoS Medicine, 8(1):e1000412. Available from: <http://www.ncbi.nlm.nih.gov/pubmed/21311585>.
Cover picture: WHO (2017). Infographics for social media: World Malaria Day. Available from: <http://www.who.int/campaigns/malaria-day/2017/social-media/en/>. [Accessed 22nd April 2018].
Tiago Canelas is a Ph.D. candidate in Global Health and Sustainability at University of São Paulo, Brazil. His interests in global health are infectious diseases, inequalities, the geography of health and geo-analysis applied in health