Horse drinking stagnant water
Experts at the Centers for Disease Control say the early detection of mosquitoes infected with West Nile virus makes it easier to see where the virus is spreading and take early action to halt the spread.
In Dallas, about 100 cases of West Nile virus infection and 10 deaths of humans could have been prevented last year if public health officials had kept track of infected mosquitoes caught in traps. Keeping tabs on mosquitoes enables public health officials to estimate the rate of infection in the local mosquito population.
Monitoring the rate of infection and the mosquito population size allows health officials to multiply the two numbers and produce a "vector." Experts at the Centers for Disease Control say the "vector" makes it easier to see where the virus is spreading and take early action to slow or halt the spread.
West Nile virus which is commonly transmitted by mosquitoes can cause fever, encephalitis and meningitis in both humans and horses. Although most people and horses that are infected don't display symptoms, a few develop a serious sometimes fatal, neurological illness.
Because of the lack of monitoring of the mosquito population and the fact that it can take three or four weeks before symptoms of infection develop, health officials are far behind in identifying the numbers infected and the spreading effects of the virus.
Experts say global warming trends forecast more epidemics as temperatures increase. Diseases that formerly only occurred in the tropics are moving northward and tend to cluster in affluent housing-dense areas with a high occupancy of homes.
Health officials say that preventing and controlling the virus requires, "an integrated vector management approach" that involves identifying potential breeding sites in winter and spring well before the mosquito season begins.
Regularly cleaning gutters, maintaining swimming pools, and providing good drainage of water around homes, barns, and stables would eliminate many breeding sites and mosquito monitoring and use of targeted pesticides are also key.
Learn more about West Nile virus in horses.