Why The Mosquito
p. 85 · Read in the full issue
W.H.O. presents-
Health Notes
Why The Mosquito Must Bite
IT seems strange that nature should have made the female mosquito a sucker of blood and carrier of disease while the male, by comparison, is a virtual hermit of the forest, feeding on nectar and plant juices. The female’s ability to suck blood is merely an aid to its functions as a mother. Generally, cne blood meal is necessary before it can develop a batch of eggs.
When the female mosquito bites a human it is merely for the food which it must have, and if m the process it also transmits malaria, that is merely incidental. It got the malarial parasite from a human it had bitten earlier.
Two to five days after the female has had her meal of blood the eggs are laid, and within one to twp days the eggs hatch out into wrigglers (larvae) which pass through four stages, feeding on organisms and debris in the water. After about a week the larvae become pupae, and in another two days out comes the mosquito.
The blood-sucking female is endowed by nature with a life span of about a month while the male has no more than a week to live.
Some mosquitoes, like the carrier of yellow fever, suck blood by day but mostly they are nocturnal feed ers. During the day the mosquito’s resting place is in dark corners in human dwellings, animal shelters, garden foliage or jungle under growth.
Certain species like the common house-mosquito fly for only several hundred yards, but the malaria mosquito often has a wider flight range of up to half a mile or even a mile and quarter. There are some species, however, like the salt marsh mosquito, which can do 82 miles or more with the help of a favourable wind. Mosquitoes are known to hibernate in all stages.
In many countries, thanks to “residual spraying” of DDT and other insecticides, malaria has ceased to be the dread scourge which it was some years back, but the mosquito is fighting back and certain species have developed resistance to in secticides. t Mr. H. W. Bullen, Secretary of the Melanesian Mission, was to journey from his Auckland head quarters to attend a Mission Synod at Pawa, BSIP, in October.