Outbreak of caterpillars (Lepidoptera) in Valle de Caracas, Venezuela.

Lepidopterism, a condition resulting from accidents by caterpillars or the adult forms of moths and butterflies, typically manifests as mild and self-limited hypersensitivity reactions. In August 2023, an unexpected number of accidents by caterpillars were noted in Valle de Caracas, Venezuela. This prospective descriptive study was conducted from August to September 2023. The sample includes both sightings and accidents reported in three regions of Valle de Caracas. A total of 32 sighting reports were recorded, including 13 accidents and 117 caterpillars. The caterpillars primarily belonged to the family Saturniidae, including genus Dirphia (86%) (Hübner, 1819) and Automeris (9%) (Hübner, 1819). Two caterpillars (2%) were identified as Megalopyge opercularis (Smith, 1797). Over half (54%) of the accidents involved children under nine years. Accidents were most common in residential gardens and parks (54%) and public parks and footpaths (31%). Skin lesions were present in all patients, and six patients exhibited systemic symptoms, primarily fever and palpitations. The study highlights a period of increasing accidents by caterpillars in Valle de Caracas, coinciding with multiple sightings of several species of caterpillars, mainly of the genus Dirphia. Not only were cutaneous manifestations reported, but cases of lepidopterism were previously unreported for this species in the country.