Effectiveness of a repellent paint against the spider Loxosceles laeta

Background: Loxoscelism is a severe reaction to the bite of the spider Loxosceles laeta. In recent years, a paint with repellent properties had been promoted in the commerce. However, there are no reports of experiments evaluating its effectiveness. Aim: To evaluate experimentally the repellent properties of a paint against Loxosceles laeta. Material and methods: Males, females and nymphs of L laeta were deposited in cockpits that allow the free displacement of the spider. Half of the cockpit was covered with repellent paint. Daily observations during one week, determined how frequently the spiders occupied the space covered with repellent paint. The experiments were run in triplicate. Results: No statistical differences in the occupancy of spaces covered with repellent paint or not covered with it were observed for nymphs (87% and 67%, respectively), males (72% and 77%, respectively) or females (91% and 84%, respectively). Conclusions: The tested paint does not have a repellent action against the spider Loxosceles laeta (Rev Med Chile 2009; 137: 240-5).