Population Control by Insects, Parasites, and Disease

Thomas Malthus (1798), William Vogt (1948), Paul Ehrlich (1968), and Alexander King of the Club of Rome (1990) all observed that insects in poor countries keep the population low, lifespans short, and childhood mortality high. All of them saw this as a good thing that would save the environment from damage by supposed human overpopulation. Note that the myth of overpopulation has continued since the eighteenth century to the present day among  strong population control organizations such as Planned Parenthood, Marie Stopes, UNFPA, UNESCO, Population Council, Club of Rome, and until recently USAID.

Malaria and Other Insect-Borne Diseases as Effective Tools for Population Control

Most of the diseases of poor countries are either caused, carried, or vectored by insects such as mosquitos, flies, fleas, lice, and parasitic worms, mites, and flukes, as well as contaminated water. Malaria is one of the deadliest insect-borne disease. It is the second most deadly disease in the Africa and the developing world, just behind tuberculosis. Why is malaria worse than other insect-borne diseases such as yellow fever or dengue fever? Is it because more insects carry it than any other? No, it is because it produces incomplete immune response with two outcomes: horrible, quick death or chronic recurrent bouts with severe anemia, organ and tissue damage. Because of incomplete immune response, protection from a previous infection is temporary, making reinfection possible. The malaria parasite is most effective if it does not kill the host outright, but rather keeps the host alive but badly compromised. It is difficult to control because it goes through two types of hosts, one of which has an aquatic life cycle phase and one of which can carry it for life unless treated.

Other insect-borne diseases present similar problems with control and eradication. These diseases further erode the suitability of the people for work that could raise them from abject poverty to a higher standard of living. In addition to insect-borne diseases, contaminated water is a major source of infection and disease, especially dysentery, amoebic dysentery, diarrhea, cholera, typhoid, polio, and giardia, which kill many infants and children before their fifth birthday. From all of this, it is evident that medical facilities, hygiene education, proper waste disposal, clean water, and insect eradication are critical to reducing and treating diseases and maintaining a healthy, strong workforce.

We are all familiar with the mosquito as a vector and/or carrier of malaria, yellow fever, dengue fever, chikungunya, zika, and various encephalitis types. What is sometimes forgotten or overlooked is the huge contribution by flies that carry and spread major diseases. As a specific disease, tuberculosis (TB) is the top killer in these countries; the second is malaria; additionally, the many diarrheal diseases from contaminated water are the top killers of infants and children under five. Tuberculosis is often carried by flies from feces or sputum of infected people to infect healthy children. Flies can spread many other serious diseases. Worms can cause diseases and are prevalent in poor countries, including hookworm, pin worm, round worm, tape worm, whip worm, and liver fluke. For example, hookworms can be acquired through bare feet on infected soil. Pin worm eggs are so tiny they can be inhaled or ingested in dust.  From there most of these worms make their way to the gut where they sap the strength of the host while laying eggs that leave the body through the anus and drop to the ground to infect the next host. Using raw human waste to fertilize crops adds to this menace so hygiene such as proper toilets and clean water are critical as well as shoes to prevent worms.

Since malaria is a major insect-vectored[1] disease, it deserves a closer look. The transmission of malaria is far from simple, with several points where the cycle can be stopped. It is not communicable from person to person because part of its life cycle requires a mosquito vector. Mosquitos aren’t born infected. They must acquire the parasite from an infected human. No infected humans means no malaria infected mosquitos. It takes days to weeks for a mosquito that picked up the parasite from an infected person to transmit it to a healthy person. This is called the incubation period. After the incubation period, it can bite more than one human, but this is limited by the amount of blood it can consume. The lifespan of a mosquito is about the same as the incubation period, so time can be used to defeat it. Let’s look at the stages of its life cycle to identify key points when the cycle can be interrupted.

The Life Cycle of Malaria and the Mosquito

(points to stop the cycle are marked with an asterisk)

1. An uninfected female Anopheles mosquito emerges from the surface of standing water. *(You can kill the mosquito by emptying standing water or spreading a thin film of oil on the water to kill larvae.)
2. It then bites a symptomatic person infected by the malaria protozoan and acquires the malaria gametocyte stage from their blood. *(protect and treat symptomatic humans; kill mosquitos)
3. Gametocytes move to the mosquito’s mid gut.
4. In twleve days the gametocytes mature and sexually reproduce, forming the sporozoite stage. *(kill mosquitos during this time)
5. Sporozoites move to the mosquito’s salivary glands.
6. Mosquito bites an uninfected human and transfers sporozoites to their blood. *(Protect humans; kill mosquitos.)
7. Sporozoites migrate to the liver and infect it.
8. In ten days sporozoites sexually reproduce to form the merozoite stage.
9. Merozoites re-enter the bloodstream and infect red blood cells.
10. Red blood cells are killed as the merozoites use the hemoglobin to asexually reproduce forming the gametocyte stage.
11. The red blood cell bursts releasing gametocytes and merozoites, which can form more gametocytes inside other red blood cells.
12. Person suffers fever, shakes, pain and debilitating weakness. *(Protect symptomatic humans; give anti-malaria drugs as early as possible.)
13. Gametocytes infect other tissues of the body causing damage to kidneys, liver, heart, brain, and other organs.
14. If malaria species is Plasmodium falciparum (the most prevalent type), red blood cells become sticky, may clump, cause clots, and block arteries, causing stroke or heart attack.
15. If the infected person dies, the cycle ends. If the infected person lives, only incomplete immunity is acquired so repeated infections are possible.
16. Anti-malaria drugs can kill the infection and cure the disease if caught early before permanent damage occurs.
17. Each bout with malaria, Plasmodium falciparum, destroys red blood cells equivalent to a pint of blood, leaving the person chronically anemic, weakened and possibly with permanent kidney or liver damage. Cerebral malaria can kill in as little as one day after symptoms appear.
18. A newly hatched female Anopheles mosquito bites the infected person and acquires gametocytes. *(Protect symptomatic humans; kill mosquitos)
19. The cycle repeats. See number 2 above.
20. Meanwhile, using the blood ingested, the original mosquito mates and lays eggs on the surface of standing water. Anopheles mosquitos lay single eggs, not rafts like Aedes species. *(Cover or drain standing water; apply oil to water surface; kill mosquitos.)
21. Malaria is not transferred to the eggs so that eggs, larvae, and emerging adults are free of infection. *(Cover or drain standing water; apply oil to water surface.)
22. In forty-eight hours, the eggs hatch and sink to the bottom to feed but must come to lie on the surface to breathe. (Anopheles do not have siphons like Aedes species) *(Cover or drain standing water; apply oil to water surface.)
23. Larvae eat microscopic organisms and may be eaten by predators such as frogs, fish, and the like.[2] *(Raise fish in standing water ponds or streams.)
24. Larvae molt four times and pupate on the fourth molt.
25. Pupae lie on the surface, don’t eat but respond to light, move, and can sink to the bottom to avoid predators.
26. In two to four days, a new adult emerges from the surface of the water. *(Kill mosquitos.) Cycle repeats. See number 1 above.
27. Life cycle of an adult mosquito is typically seven to ten days but may be as much as thirty days.

The Bad News

1. Malaria infection does not result in complete immunity to malaria, so reinfection is possible.
2. Malaria parasite is a protozoan called a Plasmodium, not a bacterium or virus so developing a vaccine, if possible, has been an elusive goal.
3. Relapse of malaria from dormant Plasmodia within a victim can occur over months or years.
4. Each bout destroys red blood cells equivalent to a pint of blood, resulting in severe anemia.
5. Malaria can travel to many areas of the body and cause kidney or liver damage, heart attacks, or strokes from clots.
6. Cerebral malaria can cause death in a matter of hours.

The Good News

1. Mosquitos are born clean – they don’t pass on the disease through their eggs to offspring.
2. Mosquito eggs, larvae, and pupae must breathe air at the water surface and live in the water for five to fourteen days to adulthood. They may be eaten by fish, birds, amphibians, insect larvae, among other things. Water may drain or dry up. Cover water containers to prevent egg laying. Drain standing water every four days.
3. Malaria is species specific. Human malaria is only acquired from other humans, not animals. Animal malaria species aren’t transferable to humans. One exception is human cases of Plasmodium knowlesi, which is a monkey malaria found in Southeast Asia.
4. Adult mosquitos, on average, live only one to two weeks, but sometimes up to four weeks.
5. Mosquitos acquire gametophyte stage from infected humans, which converts into sporozoite stage in five to ten days before infection of other humans is possible.
6. Person-to-person transmission is not possible, but one sporozoite infected mosquito may infect more than one human at the same time.
7. Mosquitos bite humans and pass sporozoites, which go to the liver to convert to merozoites in ten days.
8. Merozoites infect red blood cells and produce multiple gametophytes in ten to thirty days.
9. A second clean mosquito bites and picks up gametophytes. The cycle repeats.

Malaria Eradication and Prevention Plan

• • Spray interior walls of homes with DDT. This not only kills mosquitos but is a deterrent to mosquitos entering the area.
  • Close houses with screens over windows, doors, roof vents, floor gaps to prevent insect entry (preferably wire screens, but netting similar to bed nets can be used on windows, doors and roof vents, etc., but must be checked regularly for holes.)
  • Metal or tile roofs with covered roof vents are preferable to thatch, in which mosquitos can hide.
  • Use bed nets treated with insecticides.
  • Use DEET insect repellant when outdoors.
  • Cover or drain standing water at least every four days.
  • Protect infected people from mosquito bites.
• Mass administration of anti-malaria drugs for an entire village at once with insect control can end the cycle. (No infected humans means no infected mosquitos.)
• The aim is to eliminate infected human hosts, not the entire mosquito population, which is much more difficult or impossible.

[1] Vector means the disease/parasite must spend part of its life cycle developing inside the insect before being passed on to complete its lifecycle inside a human or animal.

[2] Larvae of dragonflies, Dobson flies and elephant mosquitoes (mosquito eaters), diving beetles (water tigers), and the water scavenger beetles are among insect predators that eat mosquito larvae. Dragonflies are predatory as both larvae in water and as adults. Dobson fly larvae in water are often called hellgrammites and are predatory. Mosquito eaters look like mosquitoes but are much larger than those that attack humans and animals. Most of them are harmless because the adults only feed on other insects, as well as plant nectar and similar materials.

References:

[1] Robert S. Desowitz, 1991, Malaria Capers, More Tales of Parasites and People, Research and Reality,

[2] E. J. L. Soulsby and William R. Harvey, “Disease Transmission by Arthropods,” Science 176, no. 4039 (1972): 1153–1155.

[3] See earlier blog DDT Needed Now in Underdeveloped Countries

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The book: Saving Africa from Lies that Kill: How Myths about the Environment and Overpopulation are Destroying Third World Countries will be published in October, 2018. Print and e-book will be available online and in bookstores.

My first book, Perverted Truth Exposed: How Progressive Philosophy has Corrupted Science was published in 2016. It is available in print and e-book, on line only, through World Net Daily store, Amazon, Books-A-Million and Barnes & Noble.  See the companion blog at www.realscienceblog.com  for related posts and pages.