THE FLY NUISANCE

New Zealand Listener, Volume 6, Issue 138, 13 February 1942, Page 9

THE FLY NUISANCE

(Written for "The Listener" by DR.

H. B.

TUR

BOTT

Director of the Division of School Hygiene,

Health Department )

untimely, cool and damp in most districts. The hot weather will come, however, and with it. the household invasion of flies of all kinds, the ordinary and the lesser house-fly, the stable-fly, the blow-fly, and other nuisances of the fly family. The common house-fly invades the living rooms, especially kitchens, whenever hungry He is attracted by human food, and contaminates it, worst luck! That is why he-the common house-fly-is important from a health point of view. The other breeds of flies-probably 10 per cent. or less of flies in houses-excepting the few blow-flies — don’t fancy our food, don’t damage it, and are only a nuisance. S" far this year’s summer has been A Real Danger I hope you have no illusions about the common fly. Common flies constitute one of the real health dangers of everyday life, worsé in the warm weather when they breed rapidly. A batch of eggs can turn into a brood of flies in about a week in favourable weather. In another week or fortnight those very flies will themselves be laying eggs. In our climate they choose, for breeding places, horse manure if they find it handy, or exposed human faeces, or any decaying and fermenting organic matter -for example garden and house refuse are very com. mon breeding places, Cow dung may be used and quite commonly chicken dung in fowl runs. They don’t travel far, not more than a quarter of a mile as a rule. So if your house is favoured with flies, search nearby for the breeding places. If they are on your own section you can

deal with them. If your neighbour keeps fowls or a horse or cow in a vacant section it may take a little tact to persuade him to gather and render the manure harmless. In the Winter-time Where do the flies go to in wintertime? The explanation is simple. The last autumn hatchings do not usually develop beyond the pupa (or chrysalis) stage. The fly remains in this stage in the soil until the warmth of the following spring. This is the fly danger! Human faeces contain living germs of certain dangerous | diseases. Such material powerfully attracts house-flies. They feed on it, swallowing any germs present as they do so. Human food is next in power of attraction for house-flies, and they’ll pass directly from faeces to food. The housefly’s excrement is voided at frequent in- | tervals as it feeds. Disease germs may be deposited directly upon human food, and upon eating or drinking utensils, In addition, the fly’s vomit is used to liquify solid food such as sugar, germs being deposited the whole, or the fly’s hairy legs or body may indirectly foul our food with germs. It is in these ways that flies spread summer or epidemic diarrhoea, dysentry, typhoid fever, and event tuberculosis, Preventive Methods The best attack on the fly nuisance is preventive — stop them breeding rather than attempt to kill the swarms of adult flies. Manure should be close packed, or treated with a preventive spray. A good’ spray is made with 1 oz. arsenite of soda, % Ib, treacle, mixed as a stock solution with 214 pints of water. Mix thoroughly and add 10 pints of water at using time. Household rubbish should be kept in|

really flyproof receptacles, or burnt in the incinerator; garden rubbish should be burnt, buried or sprayed. Adult flies should be killed by spraying or fumigating rooms, or trapped, swatted, caught in tanglefoot strips, or poisoned. An ounce of formaline in a pint of sweetened water, or milk and water, is suitable for placing in receptacles round rooms out of reach of children. Lastly, all foodstuffs must ‘be protected from flies, and éating and drinking utensils kept in cupboards or covered from flies between meals. Take special care to protect everything-food and utensils-that baby uses, if you want to avoid summer diarrhea. (Next week: "Cancer Has No Favourites," by Dr. Turbott.)