Malaria and Water Bodies: Strange Bedfellows
15 July 2009
Malaria is a parasitic infectious disease characterized by cycles of chills, fever, and sweating. It is caused by a parasite known as Plasmodium in red blood cells, which is transmitted to humans by the bite of an infected female anopheles mosquito. Etymologically, malaria derives its root meaning from the Latin or Greek “Mala Aria” that signifies “bad or foul air”. To go by this connotation, one can quickly attribute malaria to poor hygienic condition and most likely to dirty stinking water. Interestingly, expert opinion holds that anopheles mosquitoes breed in fresh or occasionally brackish water.
Water bodies exist in various forms and varying degrees – from standing water in the house and potholes on the road, uncontrolled runoffs in gutters, and poor drainage systems in built-up urban areas to streams, rivers, lakes, waterfalls, man-made reservoirs, seas and oceans. Keen to note is the continuous water cycle that enables for evaporation, precipitation, planting and growing of crops and trees. Water is a source of life as we drink it, cook and wash with it in its abundance from springs, wells, fountains and public taps.
Unfortunately, standing water leads to malaria. Today, malaria occurs mostly in tropical and subtropical countries, particularly in Africa south of the Sahara, South-East Asia, and the forest fringe zones in South America. The ecology of the disease is closely associated with the availability of water, as the larval stage of mosquitoes develops in different kinds of water bodies. The mosquito species vary considerably in their water-ecological requirements, (sun-lit or shaded, with or without aquatic vegetation, stagnant or slowly streaming, fresh or brackish) and this affects the disease ecology. Climate change (global warming) appears to be moving the altitude limits of malaria to higher elevations, for example in the East African highlands and Madagascar(www.who.int/water_sanitation_health/diseases/malaria/en/).
The construction of irrigation systems and reservoirs in some parts of the world can have a dramatic impact on malaria distribution and on the intensity of its transmission. Dams in Cameroon such as the Lagdo, Edea and the more recent Lom Panga under construction constitute a huge danger in the spread of malaria to the communities where they are found.
In Cameroon, malaria still remains the number one killer disease. It is a public health concern, and a menace to socio-economic development of the country. Pregnant women and children under-five are the most vulnerable group. Although preventable and easy-to-treat, the disease continues to exert a ravaging impact on the population in both urban and rural settings. According to the Demographic and Health Survey (DHS,2004), malaria is responsible for 35-40% deaths in health structures, 50% deaths in children under-five, 40-45% medical consultations, and 30% hospitalisations. The disease is also responsible for 26% absenteeism from work and consumes 40% of household budgets.
That notwithstanding, fighting against malaria in Cameroon is still a great jigsaw puzzle to solve. Synergistic efforts to tackle the disease have met with enormous challenges such as: insufficient funding, the absence of a vaccine, and parasite resistance to antimalarial drugs, the lack of infrastructures, poor management of water sources and diverted attention to HIV&AIDS.
The World Health Organisation (WHO) estimates 300-500 million cases of malaria in the world, with over one million deaths each year.
The main burden of malaria (more than 90%) is in Africa south of the Sahara with an estimated annual number of deaths over 1 million. Two thirds of the remaining burden hits six countries: Brazil, Colombia, India, Solomon Islands, Sri Lanka and Viet Nam. In many parts the natural habitat sustains intense malaria transmission; in others, water resources development (irrigation, dams, urban water supply) has worsened the transmission intensity and caused the distribution of the disease to spread. In yet others, for example the Central Asian republics of the CIS, malaria has returned as a result of a breakdown in water management and maintenance problems of local irrigation systems.
Fighting against malaria usually entails vector control, one of which has to do with identifying the possible mosquito breeding sites and destroy. This can be done by filling in and draining water bodies and through other environmental management schemes. Countries and communities are being encouraged to do so where and when appropriate. WHO's Strategy for Malaria Control, which forms the basis of the Roll Back Malaria (RBM) initiative, identifies four main interventions: (1) reducing mortality, particularly among children, by early case-detection and prompt treatment with effective anti-malarial drugs; (2) promoting the use of insecticide-treated bed nets, especially by children and pregnant women; (3) prevention of malaria in pregnancy by applying intermittent preventive therapy and (4) ensuring early detection and control of malaria epidemics, especially in emergency situations.
The Global Malaria Action Plan (GMAP) also prescribes tools such as long-lasting insecticidal nets (LLINs), indoor residual spraying (IRS) and intermittent preventive therapy during pregnancy (IPTp) as well as assuring prompt diagnosis and treatment on a much larger scale of cases of illness.
By and large, fighting against malaria entails a personal and collective engagement reason why emphasis is laid on personal hygiene and sanitation. Communities are therefore advised to actively involve themselves to fight against malaria by learning to do things by themselves. And this only possible if they prove to be malaria competent in order to count malaria out!
