Night Lights Mean Added Disease

A boy with Chagas" disease—transmitted by kissing bugs—has tell-tale swelling around his right eye.

There’s an unlikely force driving up illnesses from insects—night-time lights. Artificial lighting—particularly now in tropical regions—can alter human and insect behaviors in ways that can speed transmission of insect-borne diseases, according to a new report in Environmental Health News. Insects are drawn to artificial lights, and the lights can act as signals, drawing them closer to their human targets. Specific insects carry specific diseases, the report notes: "kissing bugs carry Chagas" disease [which leads to swelling and pontential life-threatening heart and digestive disorders], mosquitoes bring malaria and sand flies transmit leishmaniasis [resulting in large skin sores that can later bring spleen and liver damage]. Biting often occurs at night."

When researchers from Brazil combed through data to find out if artificial lights were having an impact on transferring diseases, they found a definite connection. The kissing bugs—attracted to household lights—were passing on Chagas" disease by defecating on home gardens or biting pets. Sand flies were also drawn to artificial lights and likely to bite animals living near to people. And while mosquitoes aren’t attracted to artificial lights—those lights allow people to stay outdoors longer, increasing their likelihood of being bitten, and contracting leighmaniasis.

"While artificial lighting is obviously a major benefit, it also changes behaviors that can contribute to increased disease transmission by attracting insect carriers and encouraging people to stay outside after dark, the authors conclude."

SOURCE: Environmental Health News.