In this way a small brown tumour arises, over which, at the commencement, the skin is not reddened; after some days, however, it becomes inflamed; in the centre of it a small opening is seen. If the parasite is not extracted the skin that lies over it becomes destroyed by suppuration, and thus becomes removed. At the commencement the part affected itches, with increasing inflammation; the symptoms of irritation become more severe and may amount to actual pain. If the small suppurative processes be neglected, inflammation and gangrenous and septic processes may arise. The region of the body sought out by preference by the sand flea is the sole of the foot, the toes, under the free ends of the nails and the digito-plantoid folds—more rarely the scrotum, thigh and other parts are attacked (Scheube[1073]). The number of parasites found on one person may amount to several hundreds.

Treatment consists in the removal of the parasites from the skin with a needle or a small sharp knife and the application of a bandage. Rubbing the feet with copaiba or Peru balsam, sprinkling them with insect powder, or washing them with bay rum (Berger[1074]) acts as a prophylactic or removes the irritation of the skin produced by the parasites.

Myiasis.

Under the name of myiasis we designate the complex symptoms which parasitic dipterous larvæ give rise to in man (Braun), and we conceive under the term myiasis externa (dermatosa s. cutanea) all lesions of the human integument caused by fly larvæ and of the cavities covered with mucosa therewith connected, such as the external auditory meatus, the oro-nasal cavity, the urethra and vagina. The occurrence of dipterous larvæ in the digestive tract is named myiasis intestinalia or interna.

Myiasis externa.

The larvæ of a species of fly belonging to the Muscidæ, Lucilia macellaria,[1075] are found in relative frequency in the nose, especially in America and India.[1076] Riley[1077] has stated that the screw-worm of Central America and of the United States is nothing else than the larva of Lucilia macellaria, and also that the Brazilian fly named “berna” may be no other than Lucilia macellaria. Their offspring may set up inflammatory disturbances in the soft tissues of man. This fly has a wide distribution, from the Argentine Republic to Canada, also in the British portions of the East Indies, where the disease is named “peenash.” This word is derived from the Sanskrit, and is said to be a collective name for all diseases of the nose. Lahory[1078] states that within a period of nine years ninety-one cases of “peenash” occurred in Allyghar, two of these ending fatally. Lucilia macellaria is not at all timid but bold, like the house-flies and blue-bottles, its relatives. It not only lives at no great distance from human dwellings, and forces its way into villas and country houses, but even attacks its victims without awaking them from their sleep. Although this species shows a certain preference for nasal cavities affected with catarrh or pus (v. Frantzius[1079]), and also the external auditory meatus, as well as ulcerated or wounded parts of the body, and even badly ulcerated skin carcinoma (Lutz[1080]), it is not a rare thing for it to penetrate into one of the above-mentioned cavities rapidly to deposit its eggs, without these parts having been previously affected. The report also of Conil,[1081] in which these flies bear the name of Calliphora anthropophaga[1082] is an interesting one. Probably it was the same species of Muscid in the cases of myiasis nasi observed by von Tengemann, Delasiauve,[1083] Weber,[1084] Mankiewicz,[1085] and Kirschmann.[1086] In the case recorded by Prima,[1087] and in that recorded by Britton,[1088] the issue was a fatal one; in the latter the larvæ escaped through the pharynx and nose; the hyoid bone and the soft parts of the palate were destroyed, the speech and power of swallowing were hindered. At the post-mortem extensive destruction of the internal nose was found, so that the nasal bones could only be kept in their position by the aid of the external skin. Even during life 227 larvæ escaped. Similar destructive processes were found in the case communicated by Richardson.[1089] In two cases reported by Schmidt[1090] 300 and 350 larvæ were respectively removed from the nose, and the patients recovered. Wolinz[1091] found his patient had lost consciousness, and that in the pus filling up the entrances to the nose numerous larvæ were moving; recovery followed. In the case communicated by Adler,[1092] more than 150 larvæ escaped from the nose of an old man. Curran[1093] states that people suffering from “peenash” frequently die from meningitis. The cases reported by Pierre[1094] related to the forms of severe myiasis frequently to be observed in Guiana. In a patient who was suffering from typhus (? typhoid), Douglas[1095] found the conjunctival sacs full of larvæ; in two other individuals the nasal cavities were attacked.

The case observed by Summa[1096] was that of a man, aged 28, who suffered from nasal obstruction, fœtor, epistaxis and pain in the nose. Out of seven of the cases occurring at Fort Clark, U.S.A., and in its neighbourhood, six ended fatally; in all these cases Kimball[1097] diagnosed ozæna; attracted by the strong odour the flies forced their way into the noses of the patients when asleep and there deposited their ova. In a case reported by Carrière[1098] an abscess of the nasal septum was produced by the larvæ of flies; Chiodi[1099] reports seven cases of myiasis due to Lucilia macellaria; among these was a case of rhinitis myiatica, in which a cerebral abscess leading to a fatal termination developed, being produced by the migration of a larva into the brain. Among the three cases of Lesbini[1100] was that of a girl, aged 16, with 250 larvæ in the diseased nasal cavity. Quintano[1101] observed larvæ beneath the eyelids in one case. It is possible that the cases of Cesare[1102] and Calamida[1103] were those of myiasis nasi due to Lucilia macellaria. The larvæ are also found in the nasal accessory sinuses, as is seen from the cases reported by De Saulle[1104] (frontal sinus), Delasiauve[1105] (frontal sinus), MacGregor[1106] (antrum of Highmore), and Bordenave[1107] (antrum of Highmore).

If a survey is made of the literature of the cases described of myiasis nasi produced by Lucilia macellaria[1108] the following information is forthcoming: In Europe this form of the disease is of very rare occurrence, whilst in America and India[1109] it is frequent. Persons suffering from ozæna are rendered the most liable to danger as the penetrating odour entices the flies in tropical countries with intense frequency, so much so that v. Frantzius does not consider this myiasis as an independent disease, but as a complication of ozæna of frequent occurrence in warm countries. The infection is so far of interest in its nature, in that it only takes place during the day. The fly is on the wing only by day when the sun is shining, and consequently only deposits its eggs at this time. Therefore persons suffering from ozæna are principally exposed to the danger of being pursued by the flies when they succumb to sleep during the mid-day hours in the open or in dwellings that are not closed up.

Headache is the symptom which most troubles the patients. It extends over the whole cranium and persists uninterruptedly, with more or less severe periods. Violent headaches in the frontal and buccal regions are almost always present in this complaint; they are experienced either only on one side or on both simultaneously; sometimes the pain is extended to the lower jaw and region of the neck, following the whole extent of the trigeminal nerve. The inflammation of the nasal mucosa produced by the penetration into it of the larvæ extends right into the frontal sinus and antrum. Simultaneously the patients, at the height of their trouble, suffer from persistent sleeplessness and severe vertigo, so that they reel and cannot walk straight; excessive sneezing always sets in at the commencement. The larvæ immediately spread over the nasal mucosa to seek a place suitable to feed, and irritate the nasal mucous membrane by the tickling sensation they produce. Later the patients frequently sneeze when the maggots move to and fro.