Malaria Carrying Mosquitoes, the Sixth of Africa's Big Five


I looked down at my hand and found a very thin, voracious female Anopheles mosquito preparing to bore her stiletto mouth-parts into my vein. I did what one usually does with biting insects.

In the 30 years we have lived on the mountain we have not been troubled by mossies. Our neighbor was head of the Malaria Institute in Tzaneen and assured us we were too high and too cool to sustain them.

Whether it is global warming or more contact with neighborhood states still at risk they are now up here. Another surprise is that August is very early in the year to be plagued. We will need to be more aware of the risks.

Mal-aria, bad air, is what it was called back then when the accepted cause of malarial attacks was thought to be the miasma rising from swampy ground. To an extent they were right, equating the deadly fever with the presence of still water. Mosquitoes need water to lay their eggs and as the females bite is virtually painless, it was reasonable to blame the disease on standing water.

Humans have been succumbing to malaria since earliest times, the enlarged spleens of some Egyptian mummies are surviving traces of its presence. Hippocrates described the 'autumnal fever' in Greece. The association of malaria with the Pontine Marshes in Rome was well established.

Alexander the Great is thought to have died on the banks of the Euphrates from malaria in 323 BC.

Malaria may have stopped the armies of both Attila the Hun and Genghis Khan

Even the dinosaurs may have suffered from malaria. If this is true, the disease has had ample time to exploit the immune system. Mice, birds, porcupines, lemurs, monkeys, bats, snakes and flying squirrels have malaria. The mosquito and its parasite, Plasmodium falciparum, are ancient creatures.

People knew that the fever was associated with stagnant bodies of water and many swamps were drained But no specific treatment for the disease was available in Europe until the 1630's when it was discovered that the bark of the cinchona tree was a specific cure for malaria. In the mid-19th century the Dutch cultivated the cinchona tree on the island of Java for its active ingredient quinine.

In 1939 a larvicide was used against the larvae in Brazil. Spreading oil on breeding sites was also introduced around this time. Pyrethrum was found to be effective against adult mosquitoes and in the 1940's Swiss chemist discovered the insecticidal properties of DDT. It is sprayed indoors and its effects last for months

In 1955 the WHO inaugurated its Global Malaria Eradication Campaign based on spraying insecticide in malarious areas. This resulted in the elimination of malaria from Europe, Australia and other areas. It also reduced the number of cases in India. . Unfortunately by 1969 some of the Anopheles mosquitoes had developed resistance to DDT. In 1972 the use of DDT was banned, but the WHO, in 2006, stated that there was no risk of pollution by DDT if it was properly used, and spraying programs were re-introduced.

In 1999, with the establishment of South Africa's World Heritage site, Sinangaliso Wetland Park on the Natal coast, Lake St. Lucia is now malaria free.

In 2007 the US Agency for International Deo gave $ 20M for spraying, and the William H. Gates Foundation has established projects for treating malaria and is working on a vaccine.

As an aside, Johns Hopkins University in America genetically engineered mosquitoes that were resistant to infection by the malaria parasite. But it may be a while before it applies to humans as mosquitoes have been tested only against a version of the malaria bug that sickens mice.

Chloroquine was first synthesized in Germany in 1934 and was used during WWII to immunize the armies fighting the Japanese in the Far East. Again the mosquito showed its colors and drug-resistant strains of Plasmodium appeared in the 1960's.

Researchers throughout the world have been attempting to produce a vaccine, but until this is found, the best anti-malarial care is the bednet treated with insecticide. When in known malarial areas it is advised that you avoid going outside between sunset and sunrise. Wear long sleeves, and thick trousers and socks. Insect repellant should be applied to exposed skin. Windows should be screened. Spray the room with insecticide before sunset, and burn mosquito coils or vaporizing mats.

According to National Geographic, we live on a malarious planet, even though the rich nations either ignore it or consider that the problem has been solved. In fact, it affects more people than before and is endemic to 106 nations, half the world's population.

The parasite, Plasmodium falciparum is now so entrenched and resistant to so many drugs that the potent strains can hardly be controlled. Several unprosperous regions have reached the brink of total malarial collapse, virtually ruled by swarms of buzzing, flying syringes. Zambia is one of these nations where development is almost impossible because of the sluggishness and ill health of most of the population.

World wide 500 million people are infected each year and about 2.7 million die. This is 2 deaths every minute, mostly in Africa. But malaria can be cured if the disease is diagnosed timeously, a situation not always possible in the underdeveloped world if you show any symptoms 10 to 28 days after returning home from a visit to a malaria area, see your doctor and have sufficient blood tests taken until its presence is proved, or not.

The risk of malaria is high in South America, Africa, south-east and Far East Asia. But this should be taken only as a guide as the risk can change and it is advised that expert advice be obtained before traveling to a potentially malarial destination.

You are advised to take preventative drugs a week before entering the malarial area, continue during the trip and for four weeks after returning home.

If you live in a known malaria area, it is up to you to take preventive measures. Get rid of any standing water, whether in fish ponds, bird baths, fountains, blocked gutters and empty cans or drums. A larger stretch of water can be sprayed with oil.

Some common, silly myths about malaria from Travel Health.

o Garlic, vitamin B and ultrasound devices WILL NOT protect you against malaria.
o Eating Marmite or other savory yeast extract spread WILL NOT prevent malaria.
o Staying in four or five star hotels WILL NOT stop you getting bitten or contracting malaria. Mosquitoes don't discriminate.
o Drinking gin and tonic WILL NOT stop you getting bitten or contracting malaria.

There are many more myths, but before believing anything your 'friends' tell you, consult an expert. Your life is at risk.

When the mosquito bites, its saliva enters the bloodstream and this can contain immature forms of the parasite, known as sporozoites. These migrate via the bloodstream to the liver where they are now known as schizonts. These multiply at an alarming rate, burst out of the liver and reenter the bloodstream, destroying the red blood cells in the process. After about 48 hours they are called merozoites.

The first symptoms will appear between 10 and 28 days of infection. The patient will then show signs of chills, fever, headache, muscle ache, nausea, vomiting, diarrhea and abdominal cramps. The parasites continue to multiply and unless the disease is treated, death is likely.

Diagnosis of malaria symptoms may be confused with other diseases. The only way to be sure is a blood test. Chloroquine and related drugs can relieve symptoms and prevent an attack altogether. However, some strains of the parasite became resistant to the drugs with the result that there is again an increase in malaria cases.

Information obtained from Wikipedia, Getaway, National Geographic and Letaba Herald.

Source by Ann De Ruig

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