A rare case of oral myiasis in a non-tropical region: the role of systemic vulnerability.

Myiasis is a rare parasitic infection caused by the larvae of Diptera flies, which infest the tissues of humans or animals and are typically found in warm, humid climates. Oral myiasis is uncommon in healthy individuals and typically occurs when adult flies lay eggs or larvae near the mouth or on open wounds. Malnutrition, immunodeficiency, poor oral hygiene, dental problems, neurological or psychiatric conditions, and alcoholism are the main risk factors. In this report, we present a case of oral myiasis that occurred in a patient with multiple comorbidities, including malnutrition, immunological and neurological dysfunction (lung carcinoma, cirrhosis, cachexia, Parkinson's disease). The patient was admitted to our intensive care unit while intubated because of confusion, respiratory failure, and sepsis, in which oral myiasis was identified. Due to the patient's comorbid conditions, ivermectin could not be administered. A conservative approach was used, including daily cleaning with diluted hydrogen peroxide and povidone-iodine, together with mechanical removal of the larvae. The infestation was completely resolved within three days. This case shows that oral myiasis may develop in non-tropical settings when systemic vulnerability exists. It highlights the importance of regular oral exams and mouth care for high-risk patients.