Prevent mosquito bites; reduce risks Published July 29, 2011 By Airman 1st Class Michael Scaricaciottoli 341st Medical Operations Squadron Public Health MALMSTROM AIR FORCE BASE, Mont. -- With the arrival of warm and wet weather, also comes the arrival of the mosquito. The peak biting times for most mosquitoes are between dusk and dawn; but may occur at other times throughout the day. Being outdoors for just a short period of time is long enough for mosquitoes to bite. Unfortunately, mosquitoes are carriers of some of the world's most dangerous diseases, to include Malaria, Yellow Fever, Dengue Fever and West Nile Virus. In Montana, the lone mosquito-borne illness is WNV. The first human case of WNV in this state was found in August, 2002. Since then, 507 cases have been confirmed in Montana. There were no cases reported in 2010. WNV can be a serious illness; potentially causing high fever, headache, neck stiffness, disorientation, convulsions, muscle weakness, vision loss, numbness, paralysis and coma. However, these symptoms are only seen in 1 out of 150 infected people. The more mild symptoms, seen in about 20 percent of patients are fever, headache, body aches, nausea, vomiting, and sometimes swollen lymph glands or a skin rash on the chest, stomach and back. The other 80 percent show no symptoms at all. WNV is transmitted by mosquitoes that feed on infected birds. The mosquitoes then bite humans, thereby transmitting the virus. The incubation period for WNV is 3-14 days; if someone is symptomatic, they will typically show these signs during this time period. Dead birds may be a sign that WNV is prevalent in the area. It is important to remember, however, that birds die from many other causes besides WNV. When you come across a dead bird, specifically large birds such as ravens, leave it where you find it and immediately call the Entomology office at 731-7057. All mosquitoes lay their eggs in standing water and depending on the mosquito, their eggs could hatch within one or two days. A home could be the perfect breeding ground for these biting insects. It is very important to limit the number of breeding areas around a home by getting rid of items which hold water. Some examples of possible breeding areas include buckets, the watering pans of pets, bird baths, puddles caused by leaky pipes and outside faucets, clogged roof gutters, and a pool. While mosquitoes can pose a health risk, following simple preventive measures can greatly reduce the likelihood of getting bit by a mosquito. Some personal preventive measures include: Use insect repellents that contain DEET and apply it to exposed skin. This can greatly reduce the chance of being bitten. Wear long sleeves, long pants and socks while outside to help reduce mosquito bites. However, mosquitoes can bite through thin clothing, so it is important to not only use insect repellent on exposed skin but also on clothing. The best types of insect repellent for clothing are those that contain permethrin. Additionally, CE Pest Management is taking measures to reduce the mosquito population throughout the base. These measures include larvacide application and pesticide (permethrin) fogging/misting. As always, avoid exposure to these fogging/misting operations whenever possible; however, outdoor residential misting exposures fall below the Environmental Protection Agency's (EPA) level of concern. In addition, permethrin is based on a natural insecticide found in chrysanthemum flowers and has been registered with the EPA for over 30 years. The most likely symptom, if any, resulting from exposure is short-term irritation, the risk of this increases for infants and those with asthma, allergies and hypersensitivity. This can be alleviated by promptly rinsing eyes and washing skin/clothes. By following these preventive measures, people not only are able to enjoy the warmer weather and outdoor activities without being bothered by mosquitoes, but are also helping to reduce their number. For more information, please contact the Malmstrom AFB Public Health office at 731-4405.