Myiasis incidences reported in and around central province of Sri Lanka

Myiasis, or the invasion of living tissues of humans and other mammals by dipterous larvae, is considered the world's fourth most common travel-associated skin disease after cutaneous larval migrants, pyodermas, and pruritic arthropod-reactive dermatitis.

The present study recorded the cause, anatomical position, and severity of the wounds of myiasis patients admitted to 11 hospitals located in the central region of Sri Lanka from February 2016 to July 2017.

Altogether, 28 myiasis incidences were noted within the study period. Of the total identified myiasis patients, nine were female while the remainder were male. The greatest number of patients was recorded from the Mawanella Base Hospital and Peradeniya Teaching Hospital (seven patients each). The ages of recorded patients ranged between 30 and 92 years with the average being 59.4 years. The greatest number of myiasis cases was diagnosed in wounds located in lower limbs (24). In addition, scalp, urogenital, and umbilical infestations were recorded. Eighteen out of the total patients had diabetes mellitus, and two patients suffered from filarial lymphedema. Psychiatric illnesses were a predisposing factor of larval infestation of six patients including the recorded scalp and two urogenital myiasis patients. Of the 28 myiasis cases, 27 were caused by the old world screwworm, Chrysomya bezziana Villeneuve (Diptera: Calliphoridae), and one by the blowfly, Chrysomya megacephala Fabricius (Diptera: Calliphoridae).

The awareness of patients with ulcers about this disease helps to decrease further risk of being infected by fly larvae.