Name: How Malaria Was Eradicated In The U.S.
Uploaded: 2021-06-09T17:13:06.000Z
Duration: 14 min 51 s
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Most of us probably think of malaria as a disease confined to the tropics. It

thrives in Southeast Asia, the eastern Mediterranean, parts of Central and South

America, and Africa which carries most of the global malaria burden. And when we

think of malaria we probably think of humid jungles or tropical lakes in

equatorial regions. As of 2017, 87 countries had ongoing malaria

transmission, with places like the US and Europe appearing to be safely off the

list. It's easy to assume that's because the US and Europe are not tropical

places. But in fact, both places used to be riddled with malaria. In the U.S. in

particular, it debilitated towns, caused thousands of deaths, and even determined

the settlement patterns of the country. But now it has been so thoroughly erased

that many people don't even know it used to exist there at all. So how is it that

malaria once thrived in the US, and why did it disappear? And perhaps most

importantly, can the methods of its elimination in the US be copied

elsewhere? To understand the spread of malaria in the US it's important to

consider the life cycle and behavior of the Plasmodium parasite and it's vector,

the mosquito. Malarial parasites are carried by the Anopheles mosquito which

breeds in still water such as marshy ponds and swamps, features that exist in

great numbers in the eastern and southern United States. When a mosquito

bites an infected person a small amount of blood is taken in which contains

microscopic malaria parasites, which then mate in the gut of the mosquito and begin

a cycle of growth and multiplication. About one week later, a form of the

parasite called a sporozoite migrates to the mosquitos salivary

glands. When the mosquito takes its next blood meal these parasites mix with the

mosquitos saliva and are injected into the next person being bitten.

The sporozoites then rides in the bloodstream towards the human liver. Once

it arrives, it enters a liver cell. There it undergoes many rounds of division and

multiplication. A single infected liver cell can lead to the creation of

thousands of new parasites. These new parasites then migrate to infect red

blood cells where they can hide from the body's immune system. Here they consume

the contents of the red blood cell and divide to create even more parasites.

Eventually the red blood cell they are inhabiting ruptures and the new

parasites called merozoite are released. These continue the cycle by invading

other red blood cells which subsequently also rupture. The parasites living in the

bloodstream is what causes the symptoms of malaria, which can range from

headaches, to fever, to seizures, to death if the parasites block arteries in the

brain and kidneys. At this point the parasite within the human bloodstream

can then be ingested once again by a mosquito and transmitted to another

unsuspecting human and the cycle begins again. No one knows for sure when malaria

was first introduced into humans but it is thought to have been in prehistoric

times. But as for the US its infestation with the disease was not

brought about until the 17th century with the first arrival of slave ships

from Africa. Once the parasite was introduced to North American shores

places like the wet low-lying plains of Virginia and South Carolina became

overrun with the disease. The Carolinas were initially thought of as a land of

paradise by European settlers but with the introduction of malaria became known

as a ghastly place to live. An English proverb at the time said "those who want

to die quickly, go to Carolina". Incoming immigrants thus labeled certain

colonies as healthy and others as dangerous. The Caribbean was understood

to be the most dangerous, with Florida and the Carolinas being a close second.

The Chesapeake was a bit better but only in the northern colonies - New York, New

England, and Pennsylvania, did European settlers thrive. And because most African

slaves had some tolerance to malaria and white indentured laborers from Europe

did not, demand for slave labor in malarious areas also increased. Malaria,

along with other diseases like yellow fever, thus had a substantial role in

determining settlement and labor patterns in the colonies - patterns that

would eventually lead to the Civil War. Malaria wreaked havoc in America for

centuries, and by the time of the first world war,

malaria was a huge problem, especially for the military, where men training in

the south were picking up the disease in rapid numbers. 10,500 admissions for

malaria were reported from April 1917 through December 1919, involving a loss

of 130,000 training days. By the 1930s malaria had

become concentrated in 13 of the country's southeastern states and there

were well over a million cases during the Great Depression. Malaria had become

a major national problem. By 1933, malaria deaths in America reached a new peak.

Malaria thrives when poverty is high where people lack access to adequate

health care and nutrition, and America had just descended into the Great

Depression. But for the next decade where malaria should have boomed, it instead

retreated. But the exact reason why isn't as clear as you might think. To this day

scientists and historians fiercely argue about which of the many factors was the

key to its eradication. At the time there were two camps of opinion on the best

way to get rid of malaria. The first, to attack the parasite inside the human

body. The second, to eliminate the vector for the disease, the mosquito. If it were

possible to treat all members of a community at once and eradicate the

parasite within them, then malaria could be wiped out, even if the adult

mosquitoes carry on biting everyone. For hundreds of years

people were aware that quinine obtained from cinchona bark could be used to

alleviate the symptoms of and even prevent malaria. So in 1916 scientists

carried out a study on 500,000 people in Bolivar County Mississippi,

a place plagued with malaria, to see if quinine could be used as an effective

treatment. They gave out doses of quinine for free and indeed found that it

reduced malaria infections by 90%. However even though high doses of

quinine were good for quickly ending an episode of fever and chills they found

that people would not take enough quinine on a regular basis to prevent

infection long term because of its bad side effects.

Therefore, it was useful for interrupting and infection and relieving symptoms but

more often than not the infection would just come right back. Thus quinine

distributed in large numbers definitely helped but it would not be the complete

answer to getting rid of malaria in America. It would take more than

medicating the population to get rid of this persistent disease. Once it became

known that the mosquito was the cause of malaria many people believed its death

would be the way to eliminate the disease. But killing the adult stage of

the mosquito is challenging since they infest the world in 3d space and at the

time there wasn't any reliable methods for doing so. Therefore many believed it

was best to attack the mosquito at the most vulnerable point in its lifecycle -

the larval stage. Mosquitoes lay their eggs in marshy stagnant water which then

hatch into larvae which will eventually develop into full-grown malaria

spreading mosquitoes. And so one way to hit them where it hurts is to eliminate

their breeding grounds, the marshy stagnant water. And unluckily for the

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How Malaria Was Eradicated In The U.S.

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