Introduction
Malaria is a mosquito-borne parasitic disease that causes high fever, severe chills, and sweating. [Focus, 2023] In medieval Italian "mal'aria," means "bad air", such that may coincide with mosquito habitat which includes swamps and marshes. [Boualam, 2021] It is spread by unicellular parasites of the genus Plasmodium. The infection is spread to people through the bite of Anopheles mosquitoes. [CDC, 2023]. At least 30 Anopheles species serve as vectors of human disease. [NIAID, 2016]
Malaria is mostly found in tropical countries. In 2021, nearly half of the world's population was at risk of malaria. That year, there were an estimated 247 million cases of malaria worldwide. The estimated number of malaria deaths stood at 619,000 in 2021. [WHO, 2023] The WHO African Region carries a disproportionately high share of the global malaria burden. In 2021, the Region was home to 95% of malaria cases and 96% of malaria deaths5. Children under 5 accounted for about 80% of all malaria deaths in the Region. [WHO, 2023]
Plasmodium - the causative agent of malaria
There are five main species of the Plasmodium parasite that can infect humans and cause malaria: [Stanford, 2019] Plasmodium falciparum is the deadliest malaria parasite and the most prevalent on the African continent [WHO, 2023]
Plasmodium vivax causes less serious illness, but the parasites can remain dormant in the liver for many months, known as hypnozoites during this time, causing a reappearance of symptoms months or even years later. [Adekunle, 2015] It is the dominant malaria parasite in most countries outside of sub-Saharan Africa.
P. malariae and P. ovale (including two subspecies) also infect humans. A study published in 2021 found that the pooled prevalence of P. malariae and P. ovale spp. were 2.01% and 0.77% respectively. [Hawadak]
Plasmodium knowlesi is a parasite that causes malaria in humans and other primates. [Collins, 2012] It is found throughout Southeast Asia, including Indonesia, Philippines, Vietnam, Cambodia, Laos, Thailand, and Myanmar. Furthermore, it is the most common cause of human malaria in Malaysia. [Hussin, 2020]
P. knowlesi is principally a primate malaria, while the exact proportion of infections in primates (various Old World monkeys) versus humans is not known. Approximately two-thirds of human P. knowlesi infections were of the long-tailed macaque type, and one-third were of the pig-tailed-macaque type, with relative proportions varying across the different sites. [Divis, 2015]
Monkey-to-human transmission is the main infection pathway, rather than human-to-human transmission. [Kotepui, 2020] Indeed, the majority of P. knowlesi infections likely occur in primates, with humans becoming infected through contact with these primates or their habitats. [Davidson, 2019]
Common Malaria Treatments
Chloroquine/ Hydroxychloroquine
Chloroquine/ hydroxychloroquine is a preferred medication primarily used to prevent and treat malaria in areas where malaria remains sensitive to its effects. It is usually used in combination with another antimalarial medicine to increase the effectiveness. [Mayo, 2023] [Merative, 2023]
It can also be used for prevention of malaria through pretravel dosing. Chloroquine is taken one to two weeks before traveling to an area of endemic malaria. [Kane, 2012] This helps to acclimatise the body, monitor for a reaction and provide time to alter the medication if there is a problem.
To prevent any delayed development of the disease it is recommended to keep taking chloroquine for 4 weeks after leaving an endemic area.
In many parts of the world, parasites have become resistant to Chloroquine, and the drug is no longer an effective treatment. [Kayiba, 2020] In such cases, a combination with a different or additional medication may be required. Always consult with a healthcare provider for the most appropriate treatment options.
Other medications
Other medications to treat malaria include quinine sulphate, mefloquine, atovaquone, proguanil, artemether / lumefantrine, doxycycline, primaquine, and Tafenoquine. [PHAC, 2014]
Conclusion
In conclusion, malaria, a mosquito-borne parasitic disease...
(All Rights Reserved)