In Baldwin and Mobile counties, four sentinel chickens have tested positive for West Nile virus (WNV). The three sentinel chickens that tested positive for WNV in Baldwin County were located in Gulf Shores, Magnolia Springs and Perdido Beach. One sentinel chicken was positive for WNV in the BelleFontaine area of South Mobile County.
Public Health receives positive case reports from the Alabama Department of Agriculture and Industries, and the agencies work together to identify areas of arboviral disease within the state.
According to Dr. Dee W. Jones, State Public Health Veterinarian, the significance of positive horses and chickens means the virus is present in the mosquito population. He warns that the same mosquitoes that infect animals pose a risk to humans. The confirmation of viral activity is very common in the summer and fall months. Positive case counts in the state vary from year to year based on mosquito populations. The virus can only be spread through the bite of a mosquito, and not from another animal.
"With many people enjoying outdoor activities, it is important that residents take every effort to reduce their exposure to mosquitoes," Jones said. "Keep your mosquito repellent with you at all times when you are working or participating in recreational activities outdoors."
EEE, WNV and other mosquito-borne viruses are transmitted by mosquitoes after they feed on birds. The same mosquitoes can then infect mammals, particularly humans and horses. Humans and horses can sometimes become seriously ill from the infection. Transmission to humans and horses can be decreased by persons taking steps to avoid mosquitoes and by the use of WNV and EEE vaccine in horses. According to Jones, although there is no vaccine available for humans, vaccination for horses is very important in preventing infection in these animals.
Since mosquitoes are commonly found throughout much of Alabama, health officials offer practical strategies for the mosquito season:
PERSONAL PROTECTION; CLOTHING AND AROMATICS
Wear loose-fitting, light-colored clothes to help prevent mosquitoes from reaching the skin and to retain less heat, making yourself less "attractive" to mosquitoes. Mosquitoes are more attracted to dark colors.
When possible, wear long sleeves and long pants.
Avoid perfumes, colognes, fragrant hair sprays, lotions and soaps, which attract mosquitoes.
PERSONAL PROTECTION; REPELLENTS
Follow the label instructions when applying repellents. Permethrin repellents are only for clothes--not for application on the skin.
When using repellents avoid contact with the eyes, lips and nasal membranes. Use concentrations of less than 10 percent when applying DEET-containing products on children.
Apply DEET repellent on arms, legs and other exposed areas but never under clothing.
After returning indoors, wash treated skin with soap and water.
Citronella candles and repellents containing citronella can help, but their range is limited. Herbals such as cedar, geranium, pennyroyal, lavender, cinnamon and garlic are not very effective.
PERSONAL PROTECTION; AROUND THE HOME
Mosquito activity peaks at dusk and again at dawn; restrict outdoor activity during these hours.
Keep windows and door screens in good condition. Replace porch lights with yellow light bulbs that will attract fewer insects.
Mosquitoes breed in standing water; empty all water from old tires, cans, jars, buckets, drums, plastic wading pools, toys and other containers.
Clean clogged gutters.
Remove the rim from potted plants and replace water in plant/flower vases weekly.
Replenish pet watering dishes daily and rinse bird baths twice weekly.
Fill tree holes and depressions left by fallen trees with dirt or sand.
Stock ornamental ponds with mosquito fish (fish which eat mosquitoes in their larval and pupal stages) or use larvicidal "doughnuts" which gradually kill mosquitoes.
Mosquitoes that can spread these viruses to humans are commonly found in urban and suburban communities as well as rural, freshwater swamp areas. They will breed readily in storm sewers, ditches, waste lagoons and artificial containers around houses.
It is important that homeowners do a careful inspection around their homes to be sure nothing holds water for longer than three days. In addition to surveillance activities, some county health departments also work to eliminate mosquito breeding sites and conduct larvicide and adulticide applications.
"It is reasonable to assume that mosquito-borne viruses are likely circulating between mosquitoes and birds in many parts of the state," Jones said. "Everyone should try to avoid exposure to mosquitoes."
EEE, WNV, St. Louis Encephalitis Virus and La Crosse Encephalitis Virus have been detected periodically within various areas of the state for several years. Epidemiologists point out that EEE can be more dangerous to people and other mammals than other mosquito-borne viruses, but that the same mosquito prevention measures reduce exposures to any of these diseases. The Health Department will continue to notify local officials of test results and recommend methods of prevention.