Mosquito Abatement

A principal duty of the Mosquito Abatement Coordination (MAC) Office is to conduct surveillance of mosquito-borne diseases as an early warning system. Adult mosquitoes are trapped statewide weekly from June through September. Samples are then tested at the RI Health Department Laboratory for the presence of Eastern Equine Encephalitis (EEE) and West Nile Virus (WNV). Appropriate responses are based on those results.

EEE and WNV are the two human diseases transmitted by mosquitoes in RI. Both are maintained in bird populations in nature. Mosquito species that bite both birds and mammals acquire these diseases from birds and can then transmit them to humans. EEE has a very high human mortality, but fortunately is very rare. WNV has a very low human mortality, but has become prevalent in both rural and urban environments since its establishment in RI in 2000.

The MAC Office assists communities with efforts to reduce the human risk of WNV. Since 2000 (the year WNV arrived in RI) the state has been providing product to communities to be distributed into underground storm-water catchment basins. This effort reduces mosquito production from that habitat – one that is well known to produce mosquitoes that are important in transmitting WNV.

Of course, the most effective way to reduce the risk of acquiring EEE and WNV is to reduce exposure to mosquito bites. Mosquito biting is more prevalent at dawn and dusk, in the shade and at temperatures above 55 degrees. Wearing protective clothing and using repellents containing DEET are effective ways for reducing risk. Finally, it is important to maintain screens and prevent stagnant water from collecting in artificial containers around the home.