Oral cavity myiasis in children: first demonstration in Egypt with general review

Oral myiasis: Analysis of cases reported in the English literature from 1990 to 2020

Myiasis is an infection caused by the deposition of fly larvae in tissues, and its involvement in the human oral cavity is uncommon. Herein, we have performed a data analysis of published cases of oral myiasis. A search was performed in PubMed, Ovid, Web of Science, Scopus, and LILACS. Geographic distribution, demographic data, associated factors, clinical features, fly types, treatment, and presence of sequelae were analyzed. A total of 122 articles reported the cases of 157 infected individuals. The most affected countries were India (41%) and Brazil (29.5%). Male predominance (67.5%) and a mean of 41.9 years of age were observed. The gingiva (29%) was the most affected site, followed by palate (25%) and lip (21%). There were different forms and combinations of treatments: manual removal of larvae and surgical debridement, application of asphyxiating substances, antibiotic therapy, and use of ivermectin. The condition predominantly affects individuals with neurological and/or locomotor disabilities, of low socioeconomic status, with poor oral hygiene and chemical dependence and individuals with previous injuries or with the absence of lip sealing. The establishment of a standard treatment protocol, enabling comparison in future studies and providing uniformity in treatment strategies offered by health services is strongly recommended.

Daily and seasonal variation of muscid flies (Diptera: Muscidae) in Chiang Mai province, northern Thailand

Flies of the family Muscidae, or muscids, are of medical and veterinary importance worldwide due to their recognition as nuisance pests and myiasis-producing agents. Effective control of muscids requires biological information on population dynamics daily and across seasons. In this study, such patterns were investigated in three different microhabitats (e.g., forest area, palm plantation and longan orchard) in a suburban area of Chiang Mai Province, northern Thailand. Adult fly samplings were conducted for 24-h intervals using semiautomatic traps and 1-day old beef offal as bait. Samplings were carried out twice per month from July 2013 to June 2014. A total of 3,419 muscids were trapped, comprising nine species, with Musca domestica Linnaeus accounting for the majority (n = 1,329; 38.9%) followed by Hydrotaea spinigera Stein (n = 770; 22.5%) and Musca ventrosa Wiedemann (n = 740; 21.7%). The greatest overall abundance was in the longan orchard location (n = 1,508; 44.1%). Community structure peaked during the rainy season (mid-May to mid-Oct). Peak activity during the day was late morning (9.00 to 12.00 h) for M. domestica, early morning (6.00 to 9.00 h) for H. spinigera, and early afternoon (12.00 to 15.00 h) for M. ventrosa. Temperature had no significant effect on the abundance of M. domestica (r_s= -0.030, p = 0.576) or H. spinigera (r_s = 0.068, p = 0.200), but had a weak negative correlation with M. ventrosa (r_s = -0.238, p = 0.0001). Relative humidity had a weak negative correlation with M. domestica (r_s = -0.263, p = 0.0001), H. spinigera (r_s = -0.107, p = 0.043) and M. ventrosa (r_s = -0.344, p = 0.0001). More females (n = 2,078) were trapped than males (n = 761). These results provide baseline information of daily and seasonal dynamic activity of muscid flies under natural conditions, which is the prerequisite information for effective control measures.