Mosquito and Malaria threats to public health in Angola

 

Mosquito and Malaria persistent threat

Malaria is a vector-borne disease caused by Plasmodium parasites and transmitted through the bite of infected female mosquitoes from the genus Anopheles.

Nearly every minute, a child under five dies of malaria. Many of these deaths are preventable and treatable. In 2021, there were 247 million malaria cases globally that led to 619,000 deaths in total. Of these deaths, 77 per cent were children under 5 years of age. This translates into a daily toll of over one thousand children under age 5.

Over the past two decades, a considerable expansion of malaria interventions has occurred at the national level in Angola, together with cross-border initiatives and regional efforts in southern Africa.

Plasmodium falciparum is the deadliest human malaria parasite and the most prevalent species in sub-Saharan Africa. 

According to the World Health Organization (WHO), the estimated number of global malaria deaths increased from 558,000 in 2019 to 627,000 in 2020, due in part to moderate disruptions in the delivery of malaria services during the COVID-19 pandemic.

Malaria is a major public health concern and poses the biggest health threat to pregnant women and children under five in malaria-endemic countries such as Angola. As of 2018, malaria, primarily caused by P. falciparum, remained among the top causes of mortality from infectious diseases in Angola, together with HIV/AIDS and tuberculosis. 

Malaria prevalence among children under 5 years of age decreased by 38% between 2006 and 2011, although in 2011 malaria was still responsible for 35% of all treatment demand, 20% of all hospitalizations, 40% of prenatal mortality, 25% of maternal mortality, 60% of hospitalizations in children under 5 and 35% of infant mortality. 

However, the country has achieved tremendous progress in the past two decades in ameliorating the impacts of malaria. The mortality rate from malaria has dropped by an estimated 36% since 2000, and population-wide morbidity rates due to the disease decreased from 26.6% in 2000 to 15% for 2018.

Angola has a highly diverse climate and varied ecosystems and, similarly, malaria prevalence and mosquito vectors are distributed heterogeneously across the country. Provinces of hyperendemicity (malaria incidence ≥ 30%) are located in the rainier, warmer north and northeast provinces, while the temperate central and coastal provinces have low to mesoendemic (10%  < malaria incidence < 30%), stable transmission; finally, the southern, arid regions closest to Namibia have highly seasonal (mesoendemic, unstable) malaria transmission and are prone to epidemics (malaria incidence ≤ 10%). 

Fighting malaria with long-lasting insecticidal nets (LLINs)

Sleeping under a LLIN is one of the best ways to prevent malaria, as they form a physical and chemical barrier against mosquitoes. When mosquitoes try to bite someone sleeping under a LLIN, they are not only blocked by the netting, but also killed by the insecticide coating. 

UNICEF is continuously monitoring the development of new kinds of LLIN that use other families of insecticides capable of killing the mosquitoes. “As soon as these new nets are approved by WHO, we will start offering them to the countries fighting the disease.”