Unversalisation of Chemoprevention strategies like Mass Drug Administration (MDA) and Intermittent Preventive Treatment (IPT) for Malaria Elimination
Globally, anti-malarials have been used for prevention of malaria in endemic areas for a long time now. During the 1920s and the 1930s, in Italy, antimalarial drugs were used as personal prophylaxis. Quinine was used extensively by Gorgas during the construction of the Panama Canal1. The early Colonists in India devised ingenious methods like use of ‘Indian Tonic Water’ and mass administration of Quinine tablets2. Quinine proved to be bad as a prophylactic agent and was replaced by Mepacrine during 1930s and 1940s and specially during World War II, which was also found to be rather toxic. The introduction of Chloroquine after the War, followed by Amodaquinone, Pyrimethamine, Mefloquine and in recent times, Artemisin Combination Therapies (ACT), were found to be safe and effective drugs for different approaches of chemoprevention2.
WHO3 has observed that MDA combined with residual spraying, antilarval operation and use of Insecticide Treated Nets (ITN) is quite effective in breaking the chain of malaria transmission and reduce morbidity and mortality to a large extent and recommended use of MDA in areas approaching elimination4. A Cochrane Review5 and a Systematic Review6 concluded that MDA has been successful in reducing both incidence and prevalence of malaria and should be considered as part of any robust malaria elimination strategy. The prerequisite for MDA to be successful is that the coverage needs to be high, meaning that results could be jeopardised if a large proportion of the population refuses treatment and importation needs to be prevented. Hence MDA is effective where other preventive strategies work well, community participation is high, and antimalarial drugs otherwise used, are effective to break the chain of transmission3 without development of resistance.
IPT, in which full therapeutic doses of anti malarials (mainly Sulphadoxine Pyrimethamine) are given at defined intervals7 to the pregnant women (IPTp), infants (IPTi) and young children (IPTc, also referred to as Seasonal Malaria Chemoprophylaxis). The strategies have been found to be successful in reducing malaria and its complications amongst the at risk population in high transmission zones successfully and also advocated by WHO7.
Chemoprophylaxis aims to sustain blood levels above the mean inhibitory concentration for a prolonged period, in producing protective drug concentrations to inhibit parasite growth. It has been advocated for travelers and troops deployed in the endemic areas and found to be quite efficacious and is included in the Malaria control programme in India. Mefloquin, which is used for long duration stay (>06 weeks) have proven to be highly effective for the troops deployed in the North Eastern states in India in places where Plasmodium Malaria is endemic8. Similarly, chemoprophylaxis with Doxycycline (used for <06 weeks) has been used extensively by the US Military operating at malaria endemic countries9.
Globally, there has been considerable progress in control of malaria, though we are way too far from elimination levels. In most of the malaria endemic countries, preventive measures of control of mosquito breeding as well as its adult population and use of ITNs are in place. Superior diagnostic facilities are being implemented. Newer drugs for treatment are being made available. The partial immunity produced by these chemoprevention strategies will complement the anti malarial drug treatment and other control measures in bringing down the incidence of malaria and prevent complications. However, only a few countries in Africa have adopted these strategies in their national programme though it has been advocated by the World Health Organisation (WHO)2 for global adoption. Even the countries which are practising chemoprevention, scaling up remains a challenge, possibly because of less evidence. Large scale studies are thus required to analyse the efficacy and resistance potential of the appropriate chemoprevention drugs in specific regions. Highly motivating health workers will be required to reduce the myths and increasing uptake in the general population. It will of course, require wholehearted support from the Government.
1. Brian Greenwood. The Use of Anti-Malarial Drugs to Prevent Malaria in the
Population of Malaria-Endemic Areas. Am. J. Trop. Med. Hyg. 2004;70(1):1–7
2. World Health Organisation. World Malaria Report 2017. Available at http://apps.who.int/iris/bitstream/handle/10665/259492/9789241565523-eng.... Accessed on 19 Oct 2018.
3. World Health Organisation. Guidelines for the treatment of Malaria 3rd Edition 2015. Available at http://apps.who.int/iris/bitstream/handle/10665/162441/9789241549127_eng.... Accessed on 19 Oct 2018.
4. World Health Organisation. Mass Drug Administration for Falciparum Malaria – A Practice Field Manual 2018. Available from http://apps.who.int/iris/bitstream/handle/10665/259367/9789241513104-eng.... Accessed on 28 Oct 2018.
5. Poirot E, Skarbinski J, Sinclair D, Kachur SP, Slutsker L, Hwang J, 2013. Mass drug administration for malaria. Cochrane Database of Systematic Reviews 12: CD008846
6. Gretchen Newby et al. Review of Mass Drug Administration for Malaria and Its Operational Challenges. Am. J. Trop. Med. Hyg., 93(1), 2015, pp. 125–134
7. World Health Organization. 2018. Available at http://www.who.int/malaria/areas/preventive_therapies/pregnancy/en/. Accessed on 26 Oct 2018.
8. Malaria in India. Malaria site. Available at https://www.malariasite.com/malaria-india/. Accessed on 19 Oct 2018.
9. Brisson M, Brisson P. Compliance with Antimalaria Chemoprophylaxis in a Combat Zone. The American Journal of Tropical Medicine and Hygiene. 2012;86(4):587-590.
Competing interests: No competing interests