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How do insects attack humans

How-do-insects-attack-humans-photoAll sorts of insects attack and prey upon human beings. Most common of those that attack the body directly are the lice and the itch mites. Less frequent are bedbugs and spiders. In the woods and in tropical areas chiggers and mosquitoes, ticks and the biting flies annoy mankind.

CHIGGERS

Chiggers are known scientifically as Trombicula irritans. They hook themselves on to the skin. The skin becomes irritated, and an intolerable itching begins. Red blotches appear, and blisters form. The chiggers do not burrow into the skin, but they inject a substance which dissolves and softens the tissue, and this causes the itching. 

Infestation with chiggers can be prevented by putting flour of sulphur or sulphur powder into the stockings or underclothing when going into tall grass or weeds. Protection can be had by wearing leggings and by closing off the bottom of the trousers.

If you have been seriously bitten by chiggers, wash the skin thoroughly with soap and water and allow the lather to remain on the skin ten minutes before removing. Then any of the anti-itch preparations can be applied to keep the itching under control until healing has occurred.

Insect repellents such as DDT, freon with pyrethrum, and similar preparations can be used to remove chiggers from infested areas, as well as mosquitoes, moths, and other insects.

LICE

The louse is an annoying inhabitant on the human body. Head lice are such a frequent annoyance among children in schools that health departments usually give special instructions for their control. Several specialized mixtures have been developed for getting rid of head lice, body lice, and pubic lice. 

To kill head lice, ordinary crude petroleum or kerosene mixed with sweet oil or olive oil, half and half, is rubbed well into the scalp. Then cover the hair with a piece of muslin for at least two hours or, better, overnight. Petroleum is poisonous and inflammable. Never let the hair get close to any open flame, such as a gas jet or a lighted match. When the muslin is removed wash the hair and scalp with soap and hot water and rinse well with clear water. Repeat this process as long as live vermin are found in the hair. Nits may be removed by wetting the hair thoroughly with hot vinegar, then combing with a fine-toothed comb. Dry the hair completely after such treatments before going out.

For body lice, the body, all clothing, and all bedding may be thoroughly dusted with a suitable DDT powder.

Pubic lice are commonly called “crabs.” Specialized ointments including the old-fashioned “blue ointment” and “Gammexane” ointment, are used, rubbed thoroughly into the infested areas. If such lice get into the eyelashes, they should be picked off, with their nits, by a forceps.

Itching from the bites of lice or other insects is controllable by ointments or lotions containing small amounts of phenol or menthol or camphor, such as 1 per cent phenol or menthol in calamine lotion or phenolated camphor in mineral oil.

SPIDER BITES

The only venomous spider in the Western Hemisphere is the black widow. When a person is bitten by a spider the first step is to stop the absorption of the poison into the circulation. The wound can be disinfected with tincture of iodine or any other good antiseptic. If any considerable amount of poison has been taken into the body, the area of the bite can be put under suction.
Following the bite of the black widow spider, one feels a sharp pain. Then comes swelling and redness at the bitten spot, and the whole body reacts with dizziness and weakness, tremor of the legs, and even abdominal cramps. Small children may have difficulty in breathing and even stupor or convulsions. A serum or antitoxin has been developed, but has to be secured in most cases from the health department or directly from the manufacturer.