MYIASIS 



201 



It is not certain if they attack perfectly healthy persons, 

 though in some cases no history of antecedent nasal 

 disease or discharge can be obtained. Usually there is 

 some such history, and a large proportion of the cases 

 are in lepers. The earlier the diagnosis is made the more 

 successful is the treatment, and the less the damage done. 

 The earliest symptom is some itching and irritation about 

 the nares, with a certain amount of swelling of the nose 

 and each side of it ; the loose connective tissue beneath 

 the lower lids being swollen early. The condition is often 

 mistaken for facial erysipelas. 



FIG. 77. Larva of Chrysomyia macellaria. 4/1. (After Clonel.) 



A larger species, Chrysomyia viridiila, also acts in a 

 similar manner. 



In any case where there is spreading cellulitis round 

 the nose, often shown first by marked swelling of the 

 loose cellular tissue under the eyes, this condition should 

 be suspected. Careful examination of the nares will often 

 disclose the small larvae. Thorough nasal irrigation may 

 be necessary. Plugging the posterior nares, with sub- 

 sequent irrigation, will usually bring away the larvae, 



