Ivermectin causes Cimex lectularius (bedbug) morbidity and mortality

Abstract

Background: Bedbug infestations are increasing across North America and Europe, with more people presenting to Emergency Departments for treatment. Physicians cannot provide substantive treatment for people affected by bedbugs.

Study objective: To determine if ivermectin, a relatively inexpensive and safe, long-acting oral anti-parasitic drug is able to cause bedbug morbidity and mortality.

Methods: We evaluated the effects of ivermectin on bedbugs using an artificial feeding membrane and mice and humans. Bedbug morbidity, mortality, and nymph molting was recorded.

Results: Using an artificial feeding membrane, bedbug mortality was 98% (n = 81) for 260 ng/mL ivermectin and 0% for 0 ng/mL ivermectin (control; n = 90) after 13 days. Mortality for bedbugs fed on mice injected with the human equivalent of 200 μg/kg ivermectin was 86% (n = 22), vs. 0% in the 0 μg/kg ivermectin (control; n = 21). Of the surviving nymphs, 0% exposed to ivermectin molted by day 75, vs. 80% in the control group by day 8. Bedbugs that fed once on human study subjects 3 h after consuming 200 μg/kg of oral ivermectin had a 63% (n = 24) 20-day mortality rate, vs. 8% (n = 24) in the control group. Of the surviving nymphs, 0% (n = 5) in the 3-h ivermectin group molted, vs. 80% (n = 10) of the control group.

Conclusions: It may be possible that ivermectin could help eradicate, suppress, or prevent a bedbug infestation.

Keywords: Cimex lectularius; bedbug; ivermectin; mortality; prevention; therapy; treatment.