West Nile virus (WNV) is a disease that is transmitted by the bite of an infected mosquito. Although less than 1 percent of those bitten by infected mosquitoes become severely ill, WNV can cause serious, life-altering and even fatal disease, so it is important to take the time to prevent mosquito bites. Just one mosquito bite can transmit West Nile virus or other diseases. There is currently no vaccine or specific treatment for WNV; therefore, preventing mosquito bites is essential.

Remember the Four Ds to defend yourself against West Nile Virus:

1. DUSK/DAWN are the times of day you should try to stay indoors. This is when infected mosquitoes are most active.
2. DRESS in long sleeves and pants when you're outside, especially during dusk and dawn. For extra protection, you may want to spray thin clothing with repellent.
3. DRAIN standing water from old tires, flowerpots, birdbaths, buckets, toys and clogged rain gutters in your backyard and neighborhood at least once a week. These are mosquito breeding sites.
4. DON repellent.

More information on WNV can be found at the Centers for Disease Control and Prevention (CDC).

Repellents for use on skin and clothing
CDC evaluation of information contained in peer-reviewed scientific literature and data available from EPA has identified several EPA registered products that provide repellent activity sufficient to help people avoid the bites of disease carrying mosquitoes. Products containing these active ingredients typically provide reasonably long-lasting protection:

1. DEET (Chemical Name: N,N-diethyl-m-toluamide or N,N-diethly-3-methyl-benzamide)
2. Picaridin (KBR 3023, Chemical Name: 2-(2-hydroxyethyl)-1-piperidinecarboxylic acid 1-methylpropyl ester)
3. Oil of Lemon Eucalyptus* or PMD (Chemical Name: para-Menthane-3,8-diol) the synthesized version of oil of lemon eucalyptus
4. IR3535 (Chemical Name: 3-[N-Butyl-N-acetyl]-aminopropionic acid, ethyl ester)

Surveillance for WNV and other arboviruses in Iowa
Since the 1975 St. Louis encephalitis (SLE) epidemic and introduction of western equine encephalomyelitis (WEE), Iowa has developed programs to monitor mosquito and arbovirus activity. In 2000, the program was expanded to include the detection of West Nile virus.

The program is a joint effort of the Iowa Department of Public Health (IDPH), Iowa State University Department of Entomology (ISU), the University Hygienic Laboratory , and the several local public health departments. Collaboration between epidemiology and laboratory practice are essential facets that help build an effective arboviral surveillance system.

The program relies on several components, including the following:

• Maintaining flocks of sentinel chickens that are monitored for infection with SLE and WNV.
• Tracking and reporting arboviral disease activity in humans and horses.
• Tracking the number of blood donors that are infected with WNV.
• Collection, enumeration, speciation and testing of mosquitoes for arbovirus infection.
• Education of local public health departments, healthcare providers and the public about disease prevention, diagnostics, symptoms, treatment, newly recognized modes of transmission, emerging clinical syndromes in humans, mosquito control measures (both personal and community measures).
• Dissemination of information by Internet websites (IDPH, ISU, UHL), weekly Friday Epi Update e-mail publication from IDPH, Iowa-LRN laboratory list serve and various printed educational materials.

West Nile virus activity in Iowa is posted by the Iowa Department of Public Health (IDPH).

Mosquito Surveillance Information is posted by Iowa State University .