22l6 



THE DERMATOZOIASES 



placing them (alone, without any dust) on the skin under a covering, 

 such as a piece of lint kept in place by a bandage. The pustular 

 stage did not occur, but this being due to scratching and secondary 

 pyogenic infections, there was no time for it to develop, all the 

 people refusing to go on with the experiment after the second day. 

 Some individuals seem to be unaffected by the presence of the 

 mite or the copra dust containing it. 



Symptomatology. — The hands, arms, legs, and sometimes the 

 whole body except the face, present fairly numerous, very prurigi- 

 nous papules, often covered by small, bloody crusts due to scratch- 

 ing; papulo-pustules and pustules are also generally present, The 

 eruption has no tendency to spontaneous cure while the patient 

 goes on working in the infected mills. 



Diagnosis. — On superficial examination the condition may be 

 easily mistaken for scabies, but burrows are not present and the 

 two parasites are very different. 



Treatment. — The best treatment is the daily application of 

 /^-naphthol ointment (5 to 10 per cent.). The action in these cases 

 cannot be compared to what takes place in scabies, because in copra 

 itch the acarus-like parasite remains for only a short time on the 

 body, and in most cases when the ointment is applied at night the 

 mites are no longer there. It may act as an antipruritic antiseptic, 

 and in this way diminish scratching and secondary pyogenic in- 

 fections. It is probable also that a small amount of the ointment 

 may remain on the skin after the morning bath and be repellent to 

 the mite, in this way preventing the daily reinfection which other- 

 wise takes place. 



Grain Itch. 



Synonyms. — Straw itch, Barley itch. Dermatitis Schambergi, Urticarioid 

 Dermatitis, Dermatitis Ditropenotus, Aureoveridis, Acara Dermatitis urti- 

 carioides, Schamberg's disease, Straw-mattress disease. Cotton-seed Dermatitis. 



Definition. — Grain itch is a dermatosis caused by Pediculoides 

 ventricosus Neuport, 1850 {vide Figs. 343-345, p. 728). 



History. — During the last fifty to sixty years this disease has been 

 recognized in Europe, but only since igoi in America, when Scham- 

 berg described it. In 1909, Goldberger and Schamberg found that 

 it was caused by the same mite as in Europe. Since 1914, when 

 Willcock drew attention to the matter, it has been well known lo be 

 present in cotton seed infested with the pink bollworm, of which it is a 

 parasite, and from which it has passed to man to Egypt and England. 



Climatology. — It is found in Algeria, where it is common, and in 

 other parts of Northern Africa, in Italy, and it is said to occur in 

 India. Cases have also been recorded from France, England, Austriasf 

 and Germany. In France there was an epidemic as long ago as 185 

 in Bordeaux. In 1867 some cases were found in the department 0 

 Indre and in 1872 in the Canton of Creon. 



etiology. — The disease is caused by Pediculoides ventncosu 

 Neuport, which usually feeds upon the wheat-straw worm (Isosom 

 grande Riley), the joint worm {Issoma tritici Fitch), the Angou- 

 mois grain moth {Sitotropa ceyealella) and the caterpillars of the 



