Clinico-epidemiology of tarantula (Poecilotheria spp.) bites in Sri Lanka

Tarantulas of the Poecilotheria genus are medically important arthropods in Sri Lanka and are also found in India. This study aimed to describe the epidemiological and clinical features of tarantula bites in Sri Lanka.

We conducted a prospective observational study of patients with tarantula bites over 3.5 years in the medical and paediatric wards at two hospitals in Sri Lanka starting in February 2021. Data were collected using an interviewer-administered questionnaire.

There were 17 patients with tarantula bites of whom 15 were adults and two were children. The median age of adults was 47 years (range 26-62 years). Most were males (12/17) and were bitten in the daytime (14/17), in small jungles (8/17), and on their feet (8/17). Most (11/17) were admitted to the medical facility within 1 h of the bite. Sixteen of 17 patients developed local envenoming features including local pain in 15, local swelling in 13, erythema at the site of the bite in five, and itching in four. Three of 17 had generalized muscle pain and four were found to have painful muscle cramps.

Tarantula bites from the Poecilotheria genus frequently cause local envenoming effects but few patients develop muscle pain and painful muscle cramps.