MALARIA is a preventable and curable but deadly disease. It is one of the most debilitating tropical disorders caused by parasites that are transmitted to people through the bites of infected female Anopheles mosquitoes. Mosquitoes kill, so we should kill mosquitoes. On this year’s World Malaria Day (April 25, 2017), the spotlight is on prevention. Prevention is the cornerstone of malaria control efforts globally. Proven, life-saving malaria prevention tools, including insecticide-treated mosquito nets, indoor residual spraying of insecticides and preventive therapies for vulnerable groups are in focus.
Who is at risk?
Nearly half of the world’s population (approx. 3.6 billion) is at risk of malaria. Most malaria cases and deaths occur in Africa, and Nigeria has one of the biggest burdens. In areas with high malaria transmission, young children and pregnant women are particularly vulnerable to malaria infection and death. Outside of high-transmission areas, where populations do not acquire significant immunity to malaria, all age groups are at risk. Persons at higher risk of developing severe disease, such as infants, children under 5 years of age, pregnant women and patients with HIV/AIDS, as well as non-immune migrants, mobile populations and travellers.
Malaria is an acute febrile illness. Most malaria infections cause high fever, chills, and muscle pains. Symptoms tend to come and go in cycles. Some types of malaria may cause more serious problems, such as damage to the heart, lungs, kidneys and brain. These types can be deadly.
In a non-immune individual, symptoms appear 7 days or more (usually 10–15 days) after the infective mosquito bite. The first symptoms – fever, headache, chills and vomiting – may be mild and difficult to recognize as malaria. If not treated within 24 hours, P. falciparum malaria can progress to severe illness, often leading to death. Children with severe malaria, frequently develop severe anaemia, respiratory distress in relation to metabolic acidosis, or cerebral malaria. In adults, multi-organ involvement is also frequent. In malaria endemic areas, people may develop partial immunity, allowing asymptomatic infections to occur.
You cannot get malaria just by being near a person who has the disease. In most cases, malaria is transmitted through the bites of female Anopheles mosquitoes. There are more than 400 different species of Anopheles mosquito; around 30 are malaria vectors of major importance. All of the important vector species bite between dusk and dawn. The intensity of transmission depends on factors related to the parasite, the vector, the human host, and the environment.
Early diagnosis and treatment of malaria reduces disease and prevents deaths. It also contributes to reducing malaria transmission. A blood test is essential to check for the malaria parasite. A smear is a more sensitive test for malaria infection. The blood is examined under the microscope to identify the parasites. A Rapid Diagnostic Test (RDT) is an alternate way of quickly establishing the diagnosis of malaria infection by detecting specific malaria antigens in a person’s blood. RDTs are available in Nigeria.
Malaria can be a severe, potentially fatal disease (especially when caused by Plasmodium falciparum) and treatment should be initiated as soon as possible. Patients with severe P. falciparum malaria or who cannot take oral medications should be given the treatment by continuous intravenous infusion. Medicines usually can treat the illness. But some malaria parasites may survive because they are in the liver or are resistant to the medicine. Pregnant women, especially newly pregnant women, are up to 10 times more likely to contract malaria than women who had been pregnant before. They also have a greater tendency to develop severe malaria. It is especially important that non-immune pregnant women in endemic areas use the proper pharmacologic and nonpharmacologic prophylaxis.
In children, malaria has a shorter course, often rapidly progressing to severe malaria. Children are more likely to present with hypoglycemia, seizures, severe anemia, and sudden death, but they are much less likely to develop renal failure, pulmonary edema, or jaundice.
Most antimalarial drugs are very effective and safe in children, provided that the proper dosage is administered. Children commonly recover from malaria, even severe malaria, much faster than adults.
Insecticide-treated mosquito nets
Long-lasting insecticidal nets (LLINs) are the preferred form of insecticide-treated mosquito nets (ITNs. Always use a Long Lasting Insecticide Treated Net. Check that the net is not damaged and always ensure it is properly tucked underneath your mattress. The room itself should have additional nets attached to the windows and doors. Keep the air conditioning or fan on, as mosquitoes tend to stay out of cool rooms. In most settings, WHO recommends LLIN coverage for all people at risk of malaria. The most cost-effective way to achieve this is by providing LLINs free of charge, to ensure equal access for all.
Indoor residual spraying (IRS) with insecticides is a powerful way to rapidly reduce malaria transmission. It is effective for 3–6 months, depending on the insecticide formulation used and the type of surface on which it is sprayed.
The selection of medicines to prevent malaria depends on exposure and your health condition (such as being pregnant, being elderly or young, being sick, or having immunity or resistance to malaria, or having allergies or sensitivity to the medicine). If you are going to a location where malaria is present, it is very important to take preventive medicines and to follow the correct schedule for taking them. The majority of people who become infected with malaria do not take preventive malaria medicines or do not follow the correct dosing schedule.
Antimalarial drug resistance
Resistance to antimalarial medicines is a recurring problem. Resistance to previous generations of medicines, such as chloroquine and sulfadoxine-pyrimethamine (SP) is common. Artemisinin Combination Therapy (ACT) is now recommended for uncomplicated malaria.
Medicine to prevent malaria is most effective if you take the recommended dosage exactly as prescribed and for the length of time required. If you are to take the medicine once a week, take it on the same day of the week each week.