by Shravya Murali – Art in Tanzania internship
As a significant health problem in several tropical regions of the world, malaria costs almost 435,000 lives annually. A substantial fraction of these deaths occur in Africa. The proportion of cases and fatalities in Tanzania alone constitutes 3% of those globally. Over the past few years, the number of malaria cases has been on the rise, with a staggering increase of 3.5 million from 2016 to 2017, as reported by the WHO.
How does malaria spread?
Malaria in humans is caused by four parasites from the Plasmodium genus – Plasmodium falciparum, Plasmodium vivax, Plasmodium ovale, and Plasmodium malariae. A fifth species Plasmodium knowlesi, is a zoonotic species infecting animals. Of the five species, P.falciparum results in the most severe form of malaria and is responsible for the majority of malaria-related deaths, especially among children below the age of five.
Malaria is transmitted to humans through the bite of a female Anopheles mosquito that is infected by one of the malaria-causing parasites. The Anopheles mosquito can also spread the parasite from one human to another when it feeds on an infected human’s blood meal and later goes to bite another human.
How does malaria spread?
Four parasites from the Plasmodium genus cause malaria in humans. Human-to-human transmission can also occur through blood transfusion, organ transplant, or sharing needles containing contaminated blood, as the malaria parasite can be found on red blood cells. Malaria can also be transmitted from a pregnant mother to her child before or during delivery, which is also known as congenital malaria.
However, malaria is not contagious and cannot be transmitted through casual contact (i.e., by sitting next to someone infected) or sexual contact.
What are the effects of the disease?
Those infected with malaria often experience flu-like illnesses and fever. Symptoms usually include headache, fatigue, chills, muscle soreness, nausea, vomiting, and diarrhoea. As malaria can cause a loss of red blood cells, it may lead to anaemia, characterised by yellowing of the skin and eyes. If left untreated, malaria becomes life-threatening as it can cause kidney failure, mental confusion, seizures, coma, and death. Typically, these symptoms appear approximately 10 days after a malaria infection.
Genus – Plasmodium falciparum, Plasmodium vivax, Plasmodium ovale, and Plasmodium malariae. A fifth species, Plasmodium knowlesi, is a zoonotic parasite that infects both animals and humans. Of the five species, P.falciparum results in the most severe form of malaria and is responsible for the majority of malaria-related deaths, especially among children below the age of five.
Malaria is transmitted to humans through the bite of a female Anopheles mosquito that is infected with one of the malaria-causing parasites. The Anopheles mosquito can also spread the parasite from one human to another when it feeds on an infected human’s blood meal and later goes to bite another human.
Malaria caused by P. vivax and P. ovale may recur, and the parasites can reside in the liver for up to four years after an individual is bitten by an Anopheles mosquito. These dormant parasites may become active later and invade the individual’s red blood cells, causing another malarial infection.
How is malaria treated?
If a patient is suspected of being infected with malaria, a drop of their blood is often examined under a microscope to detect the malaria parasite. Treatments for malaria vary based on the severity of the malaria, the patient’s clinical status, the Plasmodium species causing the infection, and the patient’s prior use of anti-malarial drugs.
In Mainland Tanzania, artemether-lumefantrine, a drug that can be taken orally, is used for the treatment of uncomplicated malaria. In Zanzibar, however, artesunate and amodiaquine are used. For severe malaria, artesunate and quinine are administered intravenously to patients in both Mainland Tanzania and Zanzibar. Quinine is another drug that is only used when other medications are ineffective, as quinine is known to have more side effects than others. However, quinine is used to treat malaria in the first trimester of pregnancy as it is not known to have a significant impact on the child at therapeutic doses.
What could be done to prevent the disease?
One could consume anti-malarial drugs (i.e., atovaquone, chloroquine, doxycycline) to prevent malaria. While it is possible to provide infants and children with some of these drugs, not all drugs are suitable for children and doses are based on the weight of the child.
Apart from anti-malarial drugs, one should also prevent mosquito bites (specifically at night), which could be done by sleeping under insecticide-treated bed nets, wearing fully covered / long-sleeved clothing at night, and carrying an insect repellent.
With the increasing number of malaria cases over the years, members of the public and healthcare professionals must work together in the fight against the disease. While research on vaccination against malaria is ongoing, it is also essential for everyone to take precautions to prevent malaria.
References:
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2. Centers for Disease Control and Prevention. (2021, January 26). CDC – Malaria – About Malaria – FAQs. Centers for Disease Control and Prevention. https://www.cdc.gov/malaria/about/faqs.html.
3. Mutabazi, T. (2021, June 6). Assessment of the accuracy of malaria microscopy in private
health facilities in Entebbe Municipality, Uganda: a cross-sectional study. Malaria Journal. https://malariajournal.biomedcentral.com/articles/10.1186/s12936-021-03787-y
4. Ryan, S. J. (2020, May 1). Shifting transmission risk for malaria in Africa with climate
change: a framework for planning and intervention. Malaria Journal. https://malariajournal.biomedcentral.com/articles/10.1186/s12936-020-03224-6
5. Tanzania. Severe Malaria Observatory. (2007, January 17). https://www.severemalaria.org/countries/tanzania.
6. Thomas, D. L. (2020, March 13). Triple therapies effective and safe in malaria. News. https://www.news-medical.net/news/20200312/Triple-therapies-effective-and-safe-in-malaria.aspx.
