All breeding grounds should be burnt or otherwise done away with, such as stable manure, house and kitchen refuse, human excrement and soiled substances, also decaying vegetation as soon as possible, certainly by every sixth day. Stable manure should be kept in closed receptacles and should be removed by every sixth day to at least one mile from habitations and sprinkled with chloride of lime. All kitchen and household refuse should be burnt at once or buried in pits and covered with soil. Latrines should be as far as possible from hospitals, mess rooms and tents. Food—especially milk, sugar and fruit—should be kept screened with muslin when house-flies are about. Mess rooms and tents and hospitals should have doors and windows screened with fine wire gauze during the fly season. All possible steps should be taken to prevent them contaminating man’s food and from breeding in human excrement and from entering hospitals. When present in dwelling-houses in numbers they may be killed by fumigation with pyrethrum or sulphur.
Genus. Chrysomyia, Rob. Desv.
Chrysomyia (Compsomyia) macellaria, Fabr.; Lucilia macellaria, Fabr.
Syn.: Lucilia hominivorax, Coq.; Calliphora infesta, Phil.; Calliphora anthropophaga, Conil.
A species distributed from the Argentine to the south of the United States which deposits its ova on ulcers, in the aural meatus or in the nasal cavities of persons who sleep in the open air. The larvæ are yellowish white, 16 mm. long, are armed with two strong mouth hooks, and provided with spinous rings (screw-worm); they lie hid in the nasal and frontal sinuses, in the pharynx, larynx, etc.; they perforate the mucous membranes, even cartilage, migrate into the eyes, the cranial cavity, middle ear, and cause severe disturbances; after the mature stage, in which the larvæ leave the host to enter the pupal state, these symptoms often spontaneously abate after a lapse of eight days, leaving behind greater or less cicatrices, and consequently also defects in function of the organs attacked. Very often, however, sepsis sets in, usually with a fatal termination.
(Coquerel in: Arch. gén. de méd., 1858 (5), p. 513; 1859, xiii, p. 685; Ann. Soc. ent. France, 1858 (3), vi, p. 171; 1859, vii, p. 234. Weber in: Rec. de mém. de méd. milit., 1867 (3), xviii, p. 159. Francius, A., in: Arch. f. path. Anat., 1868, xliii, p. 98. Conil in: Bol. Acad. nac. cienc. Cordoba, 1881, iii, p. 296. Humbert, Fr., in: Proc. U.S. Nat. Mus., 1883, vi, p. 103; Amer. Nat., 1884, xviii, p. 540. Lindsay in: Journ. Trop. Med., 1902; v, p. 220, and other authors.)
Fig. 408.—The screw-worm fly (Chrysomyia macellaria).