Africa can adopt integrated approach to malaria control

20Apr 2022
The Guardian
Africa can adopt integrated approach to malaria control

The Malaria progress report 2021 by Africa Union has said Africa did not achieve its target of reducing malaria incidence and mortality by 40 per cent by 2020, and is not on track to eliminate malaria by 2030. However, Tanzania has been cited as one of the African countries to have set up-

-a strategy to eliminate malaria by the end of 2030.

According to the AU report  released recently between 2015 and 2020, malaria incidence slightly declined by only 1 per cent.  There were an estimated 232 million malaria cases (96 per cent of global total) and 611,802 malaria deaths (98 per cent of global total) in Africa in 2020.

This is an increase of 68,953 malaria deaths compared to 2019 (49,000 of deaths attributed to disruptions to malaria programmes and broader health services caused by the COVID-19 pandemic).

According to revised World Health Organisation (WHO) estimates, the number of malaria deaths is significantly higher than previously understood such as 693,617 additional malaria deaths since 2015), increasing the urgency of controlling and eliminating malaria.

World Malaria Day  is an international observance commemorated every year on 25 April and recognises global efforts to control malaria. Globally, 3.3 billion people in 106 countries are at risk of malaria. 

Malaria is a mosquito-borne infectious disease that affects humans and other animals.  Malaria causes symptoms that typically include fever, tiredness, vomiting, and headaches.  In severe cases it can cause yellow skin, seizures, coma, or death.  Symptoms usually begin ten to fifteen days after being bitten by an infected mosquito.

Malaria is a life-threatening disease caused by parasites that are transmitted to people through the bites of infected female Anopheles mosquitoes. It is preventable and curable. In 2018, there were an estimated 228 million cases of malaria worldwide.

The estimated number of malaria deaths stood at 405, 000 in 2018. Children aged under 5 years are the most vulnerable group affected by malaria; in 2018, they accounted for 67 per cent (272 000) of all malaria deaths worldwide.

The WHO African Region carries a disproportionately high share of the global malaria burden.  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.

Transmission also depends on climatic conditions that may affect the number and survival of mosquitoes, such as rainfall patterns, temperature and humidity. In many places, transmission is seasonal, with the peak during and just after the rainy season. Malaria epidemics can occur when climate and other conditions suddenly favour transmission in areas where people have little or no immunity to malaria. They can also occur when people with low immunity move into areas with intense malaria transmission, for instance to find work, or as refugees.

Human immunity is another important factor, especially among adults in areas of moderate or intense transmission conditions. Partial immunity is developed over years of exposure, and while it never provides complete protection, it does reduce the risk that malaria infection will cause severe disease. For this reason, most malaria deaths in Africa occur in young children, whereas in areas with less transmission and low immunity, all age groups are at risk.

WHO recommends protection for all people at risk of malaria with effective malaria vector control. Two forms of vector control – insecticide-treated mosquito nets and indoor residual spraying – are effective in a wide range of circumstances.

Sleeping under an insecticide-treated net (ITN) can reduce contact between mosquitoes and humans by providing both a physical barrier and an insecticidal effect. Population-wide protection can result from the killing of mosquitoes on a large scale where there is high access and usage of such nets within a community.

Indoor residual spraying (IRS) with insecticides is another powerful way to rapidly reduce malaria transmission. It involves spraying the inside of housing structures with an insecticide, typically once or twice per year.