The danger of disease from flies and lice.

  • British Museum (Natural History)
Date:
1915
Catalogue details

Licence: In copyright

Credit: The danger of disease from flies and lice. Source: Wellcome Collection.

Provider: This material has been provided by London School of Hygiene & Tropical Medicine Library & Archives Service. The original may be consulted at London School of Hygiene & Tropical Medicine Library & Archives Service.

    1/4 (page 1)
    r Museum (Natubal Hibtokv). jonomic Leaflets. No. 1. , 0 THE DANGER FROM R FLIES AND LICE. AT a time like the present, when there is a danger of the introduction into this country of epidemic diseases from abroad, and when every precaution possible should be taken to prevent their spread, it is of the greatest importance to know that the germs of many of those diseases are carried and spread by insects. Sometimes they are carried by the insect and deposited on the food or in the liquids we swallow; sometimes they are introduced directly through the bite of the insect into the blood of the person bitten. Several insects, including the house-fly and the mosquito and other kinds of biting and blood-sucking flies, as well as the louse and other species of vermin, are either known or strongly suspected to be important agents in the dissemination of disease. THE HOUSE-FLY AS A DANGER TO HEALTH. It has been clearly proved that the common house-flies, although they neither bite nor suck blood, are quite capable of conveying the germs of Typhoid, Cholera, and Infantile Diarrhoea; and there can be no reasonable doubt that they are largely responsible for the spread of those diseases. Their power for evil in this respect is greatly due to their indiscriminate habits of feeding. Habits of the Fly.—The house-fly lives not only within the house, feeding on meat, sugar, milk, and other food intended for human consumption, but spends much of its time out of doors visiting filth of every description. Coming straight from the dung-heap, garbage-pit, dust-bin or earth-closet, it may enter a house, and alight, perhaps, on the bread or meat, or fall into the jam-pot or milk-jug. It is liable always to carry with it some of the disease-germs with which it may have come in contact. These may adhere to its feet, legs, wings, or other parts of its body, or they may pass into its intestine or crop, from which later they may be ejected in its excrement, or by vomiting from its crop—a habit to which the fly is prone. Its Life-History .—As with most other insects, there are four distinct stages in the life of the fly: (1) the egg; (2) the larva or maggot; (3) the pupa; and (4) the perfect insect. The