Malaria

            Malaria is a mosquito-borne disease caused by protozoan parasites in the genus Plasmodium. It is the deadliest protozoan by body count and the most lethal vector-borne disease in human history, with an estimated death toll between 150 and 300 million (Arrow, 2004).

There are 156 known Plasmodium species, but only five infect humans: Plasmodium falciparum, P. vivax, P. malariae, P. ovale curtisi, and P. ovale wallikeri (CDC). Among them, P. falciparum is both the most common and the deadliest. However, P. vivax poses its own insidious threat: it can lie dormant in the liver for weeks or even months, reactivating without warning to cause repeated relapses (Winegard, 2019). This chronic nature makes P. vivax particularly difficult to eliminate from endemic regions, including parts of the Amazon.

Malaria is transmitted by mosquitoes in the genus Anopheles. In the Amazon, the primary vector is Anopheles darlingi (Conn, 2016). Only female mosquitoes drink blood, so only females can transmit the disease. When infected with malaria, Anopheles mosquitoes exhibit behavioral changes that make them seek blood meals more frequently (Cator, 2014), increasing the chances of transmission.

Malaria is especially dangerous for children under five, who account for the majority of deaths (UNICEF, 2018). After entering the bloodstream through a mosquito bite, Plasmodium parasites travel to the liver, where they infect liver cells and reproduce. After maturing, they burst from the liver and invade red blood cells—triggering symptoms such as fever, chills, headache, muscle pain, vomiting, and diarrhea. Severe cases can lead to an enlarged spleen, anemia, low platelet counts, hypoglycemia, kidney failure, respiratory distress, and neurological complications. P. falciparum can cause cerebral malaria and rapid death if untreated (CDC).

The malaria parasite’s shape-shifting life cycle allows it to evade the immune system at multiple stages (Harvard T.H. Chan School of Public Health, 2012). Malaria infections confer only partial immunity. Survivors may experience milder symptoms in future infections, but they are not fully protected (Winegard, 2019). The chronic relapse pattern of P. vivax further complicates treatment and control.

Malaria originated in Africa, became endemic there, and later spread to Europe, Asia, and the Americas—largely through colonization and the transatlantic slave trade (Winegard, 2019). In the Amazon today, deforestation creates ideal breeding habitats for Anopheles mosquitoes, increasing malaria risk in newly settled areas (Cannon, 2019).

Treatment typically involves artemisinin-based combination therapies (Olumense, 2010), but relapsing infections from P. vivax often require an additional drug to target the dormant liver stage—a treatment that isn’t always accessible in low-resource areas.

Unfortunately, there is a deeply flawed narrative that fighting malaria contributes to overpopulation in developing countries. This idea is not just wrong—it’s dangerous. High child mortality correlates with high fertility; when parents expect some of their children to die young, they tend to have more children as a form of security (National Library of Medicine, 1998). Since malaria disproportionately kills young children, it actually contributes to high birth rates—not the other way around.

Beyond demographics, how can developing countries grow strong economies if large portions of their populations are chronically sick? Malaria hinders education, productivity, and healthcare systems. Fighting it is not just a health goal—it’s an economic one. Those who argue against malaria eradication either don’t understand the facts or have disturbing motives, including maintaining poverty and cheap labor. This narrative deserves not just rebuttal—but condemnation.

References:

Arrow, Kenneth J. Panosian, Claire. Gelband, Hellon. (2004) Saving Lives, Buying Time

Economics of Malaria Drugs in an Age of Resistance National Library of Medicine

https://www.ncbi.nlm.nih.gov/books/NBK215638/

Malaria Center for Disease Control and Prevention

https://www.cdc.gov/dpdx/malaria/index.html

Wingard, Timothy C. (2019) The Mosquito A Human History of our Deadliest Predator Dutton

Conn, Jan E. Ribolla, Paulo O. (2016) Genetic control of malaria and Dengue Academic Press

https://www.sciencedirect.com/science/article/abs/pii/B9780128002469000053

Cator, Lauren J. Lynch, Penelope A. Matthew, Thomas B. Read, Andrew F. (May 1, 2014) Alterations in mosquito behaviour by malaria parasites: potential impact on force of infection Malaria Journal

https://malariajournal.biomedcentral.com/articles/10.1186/1475-2875-13-164

(April 25, 2018) Ten things you didn't know about malaria UNICEF

https://www.unicef.org/press-releases/ten-things-you-didnt-know-about-malaria

(December 13, 2012) Malaria parasite transforms itself to hide from human immune system

Havard T. H. Chan School of Public Health

https://hsph.harvard.edu/news/duraisingh-malaria-parasite-transforms/

Cannon, John. (October 23, 2019) Malaria surges in deforested parts of the Amazon, study finds

Mongabay

https://news.mongabay.com/2019/10/malaria-deforestation-amazon/

Olumense, Peter. (March 25, 2010) The WHO guidelines for the treatment of malaria (MTG)… World Health Organization

https://www.paho.org/sites/default/files/WHO_Treatment_Guidelines_Olumense.pdf   

(1998) From Death to Birth Mortality Decline and Reproductive Change National Library of Medicine

https://www.ncbi.nlm.nih.gov/books/NBK233814/