On October 6th, 2021, the World Health Organization (WHO) endorsed the first ever vaccine for malaria, marking this date a monumental step in the fight against one of the world’s most devastating diseases. Called the RTS, S/AS01, or Mosquirix, this vaccine combats the world’s most dangerous malaria variant, the P. falciparum variant, using protein-based technology that requires four total injections. Even as its efficacy rate is less than 50% and the funding is not yet solidified, “The long-awaited malaria vaccine,” says Tedros Adhanom Ghebreyseus, WHO’s director general, “is a breakthrough for science, child health, and malaria control.”
Malaria and Mosquitoes -- A Brief Overview
Malaria, also known as plasmodium infection, is one of the leading causes of disease-induced death in the tropical regions of our planet. It is a parasitic disease most commonly caused by mosquito bites, although other modes of transmission include from mother to an unborn child, blood transfusions, organ transplants, and through the use of contaminated medical supplies such as needles and syringes. Typical symptoms include high fevers, shaking chills, and flu-like symptoms.
While not all that are affected face death, malaria is nevertheless regarded as a severe and oftentimes fatal disease.
While many are quick to antagonize all mosquitoes as potential malaria-bearers, it is important to understand that only the Anopheles genus is capable of transmitting the disease--and typically only the female mosquitoes at that. For perspective, there are over 100 different mosquito genera (a genera is just a less specific way of categorizing animals than the species category).
In most cases, the female Anopheles mosquito becomes infected by drawing malaria-parasite infected blood from an already infected host (i.e. a human who has malaria). When they take their next blood meal, the parasites are injected into the new host along with the mosquito’s saliva.
The WHO has estimated that out of around 230 million total cases each year, a little under half a million infected individuals perish due to malaria, most of the demographic falling towards children and youth in Sub-Saharan Africa. The occurrence of a prominent disease instigating a multitude of deaths in such a concentrated region gives way to a perpetual cycle of illness and poverty. As such, malaria is one of the leading causes of the economic drain phenomenon seen in poorer countries, forcing those already financially struggling to remain under a constant state of burden.
Diseased Origins -- Malaria’s Lethal History
While historians gauge documental evidence to date malaria as far back as 3000 BCE, the disease is speculated to have impacted humankind as far back as our neolithic predecessors (around 10000 BCE). However uncertain its origins, Malaria is one of history’s few and far between constants, contributing to famous events such as the fall of Rome and certain American Civil War successes to even afflicting prominent figures such as George Washington and Abraham Lincoln.
The first incrimination of mosquitos as the transmitting vectors of disease occurred in 1897 by British medical doctor Ronald Ross. Upon dissecting the stomach of an Anopheles mosquito, he found malarial parasites--a discovery that not only earned him a Nobel prize but also debunked previously circulating theories of malaria transmission (of which had included theories such as infection through inhaling the dust of dried ponds where mosquitoes had died).
At the turn of the 20th century, malaria saw the beginnings of American governmental recognition as Congress officials attempted to control the disease. The initial request rose from 1914 during the construction of the Panama Canal in the equatorial tropics, a place especially prone to this parasitic disease. Henry Rose Carter and Rudolph H. von Ezdorf were granted funds to aid in combating malaria, and various preventive activities soon followed suit.
The CDC began the fight against malaria in 1946, primarily focusing on eradicating the disease from domestic US grounds. By 1951, the health protection agency announced malaria’s elimination from US grounds, and shifted to focus on international eradication--a mission which, to this day, still remains a central focus of the agency.
Vaccine Milestones -- The Beginnings of a Long Awaited End
After thirty long years of meticulous development, the Mosquirix vaccine finally achieved the fruits of its partnership efforts with GlaxoSmithKline--a British drugmaker--and the PATH Malaria Vaccine Initiative.
A modeling study by Alexandra B. Hogan points to both potential positives and shortcomings of the vaccine. Findings reveal that an administration of 30 million doses could potentially prevent 5.3 million cases and 24 thousand deaths--an extremely weighty accomplishment given malaria’s long historical death march that left individuals and states alike with hands bound.
However, even as Mosquirix provides hope to the fraying of such historical ropes, many like Badara Cisse, a malaria researcher at the Institute for Health Research, Epidemiological Surveillance and Training in Dakar, draw criticism to the 30% efficacy rate that doesn’t quite scale with high funding required for widespread rollout. “The reality is,” says Cisse, “that so much money has been poured into this vaccine, even when the results from studies are disappointing.”
Nevertheless, it is safe to say that the vaccine--even with a below ideal efficacy rate--marks a milestone in a world long plagued by a disease that has claimed more lives than countable. Malaria is no longer an ageless killer undefeatable by neither man nor time--the first signs of hope, especially amidst a time of COVID-19 and international turmoil, will only further feed the drive to eliminate one of humanity’s oldest foes.
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