Human myiasis in Ecuador.

We review epidemiological and clinical data on human myiasis from Ecuador, based on data from the Ministry of Public Health (MPH) and a review of the available literature for clinical cases. The larvae of four flies, Dermatobia hominis, Cochliomyia hominivorax, Sarcophaga haemorrhoidalis, and Lucilia eximia, were identified as the causative agents in 39 reported clinical cases. The obligate D. hominis, causing furuncular lesions, caused 17 (43.5%) cases distributed along the tropical Pacific coast and the Amazon regions. The facultative C. hominivorax was identified in 15 (38%) clinical cases, infesting wound and cavitary lesions including orbital, nasal, aural and vaginal, and occurred in both tropical and Andean regions. C. hominivorax was also identified in a nosocomial hospital-acquired wound. Single infestations were reported for S. haemorrhoidalis and L. eximia. Of the 39 clinical cases, 8 (21%) occurred in tourists. Ivermectin, when it became available, was used to treat furuncular, wound, and cavitary lesions successfully. MPH data for 2013–2015 registered 2,187 cases of which 54% were reported in men; 46% occurred in the tropical Pacific coast, 30% in the temperate Andes, 24% in the tropical Amazon, and 0.2% in the Galapagos Islands. The highest annual incidence was reported in the Amazon (23 cases/100,000 population), followed by Coast (5.1/100,000) and Andes (4.7/100,000). Human myiasis is a neglected and understudied ectoparasitic infestation, being endemic in both temperate and tropical regions of Ecuador. Improved education and awareness among populations living in, visitors to, and health personnel working in high-risk regions, is required for improved epidemiological surveillance, prevention, and correct diagnosis and treatment. Author summary: Human myiasis is a neglected disease caused by ectoparasitic infestations of the skin, cavities and wounds by larvae of a wide variety of dipteran flies. Here, we review available data on human myiasis in Ecuador using a national registry of 2,187 cases and other information sources (39 clinical cases). We conclude that myiasis is endemic in both temperate and tropical regions of the country with greatest endemicity in the tropical lowlands of the Amazon (estimated annual incidence of 23 cases/100,000 population). Almost half clinical cases were cutaneous furuncular myiasis caused by Dermatobia hominis, which produced single lesions that were treated successfully with oral ivermectin followed by manual extraction. Also relatively common were infestations by Cochliomyia hominivorax, found in tropical and temperate regions in the Andean highlands, which infested wounds and cavities, occasionally involving hundreds of larvae and causing severe tissue damage when unrecognized. Our data shows that myiasis is a significant and unrecognized health problem in Ecuador, is likely to be significantly under-reported, and requires improved awareness among affected populations and improved education among health professionals for its diagnosis, treatment, and recognition of fly species. [ABSTRACT FROM AUTHOR]