For Immediate Release:
Aug. 1, 2007

Contact:                                                                                
Nanci Gonder                                                              
Office of Public Information
573-751-6062

Missourians Urged to Protect Themselves, Family, Community
State’s First Verified Cases of Human West Nile Virus Reported

The first two verified human cases of West Nile virus (WNV) this year have been reported to the Missouri Department of Health and Senior Services (DHSS).  The first report of WNV infection is in a St. Louis County 40-year-old man who became ill on July 7 and was hospitalized.  The second report is an 18-year-old man from Johnson County, who became ill during the second week of July but was not hospitalized.

According to DHSS data, these illness onset dates are in line with the first Missouri cases over the past few years. The typical time frame for first WNV human cases is mid to late July. Missouri’s WNV case numbers typically rise in August and September and then decline with cooling weather. As with ticks, mosquitoes remain active and can still spread disease until the first hard frosts and freezes.

“We now see WNV every year in Missouri and anyone can be at risk of serious health problems from WNV infection. Prevention is still the best medicine, so people should take some very common-sense but effective steps to reduce their risk of infection,” said Dr. Howard Pue, State Public Health Veterinarian.

“I’m often asked why we even still look for WNV in Missouri and why we still announce WNV cases and related deaths each year, since the virus appears to be here to stay,” said Pue. “WNV does not blanket the state, but occurs in ‘hot spots’ where conditions are just right. Nature does sometimes give us signs that WNV activity is high in an area, such as virus-positive dead birds, infected mosquito pools, infected horses, and human cases. When people hear about any of these signs they need to remember to protect themselves, their families and their communities."

Pue said the number of human WNV cases saw a steady decline from 2002 through 2005, but there was an unexpected resurgence in 2006. He said the increase in cases shows that WNV is unpredictable, it can show up anywhere in the state, and that people need to stay alert and not let down their guard.

As of January 2007, federal funding cuts forced DHSS to stop testing dead birds for the presence of WNV. However, citizens can still help with tracking WNV activity in their area by reporting dead birds they see. Although birds die from many different infectious diseases as well as exposure to toxins, DHSS’ Internet dead bird reporting form is being used to track reports of certain types of dead birds that may be an early sign of WNV activity in an area. 

Crows and blue jays are likely to die when infected with WNV and therefore serve as effective sentinel species warning that there is increased risk of WNV infection in an area. Other types of birds that may also indicate an increase in WNV activity include grackles, sparrows, finches, cardinals, robins, and some birds of prey like hawks and owls. Citizens are encouraged to use the DHSS Internet Dead Bird Reporting Form so that state and local public health officials can track possible WNV activity.

Citizens and public health departments are cautioned that reports from the public are not authenticated or confirmed in any way and are subject to inaccuracies.  The web address of the Dead Bird Reporting Form is: https://webapp03.dhss.mo.gov/DeadBird/Index.aspx

The best ways to prevent infection are using an effective insect repellent containing DEET if going outside in the morning and evening (mosquitoes’ most active feeding times), and making sure homes, properties, and communities are protected by cleaning up junk, trash, and other things that can hold water and serve as breeding grounds for mosquitoes that can carry WNV.

Products containing picaridin, a repellent ingredient introduced in the U.S. in 2004, are now more widely available on the market. Picaridin is a safe, effective alternative to DEET, and may appeal to consumers because it is odorless, does not feel greasy or sticky, is less likely to irritate the skin, and does not damage plastics or fabrics. However, the Centers for Disease Control and Prevention (CDC) does not recommend using picaridin for tick bite prevention at the current concentrations available (15%).  Repellents containing DEET or picaridin should be applied to clothing and exposed skin. These repellents can also be safely used on young children by following directions on the product label.

It also helps to wear long sleeve shirts and pants when outdoors to cover the skin. Some people may want to consider staying indoors at dawn, dusk, and in the early evening, which are peak mosquito biting times. Pue added that homes should be mosquito-proofed by ensuring doors and windows have screens, and standing water that can serve as mosquito breeding habitat should be eliminated. 

Most people infected with the West Nile virus do not develop any symptoms. Sometimes, though, a flu-like illness results one-to-two weeks after exposure with symptoms such as fever, headache, body aches, skin rash, and swollen lymph nodes. Less than one percent of infected people may develop a serious illness that includes encephalitis (inflammation of the brain).  These people might experience headache, high fever, neck stiffness, disorientation, convulsions, and muscle weakness. Infection may prove fatal, especially among the elderly, in a small number of those who develop encephalitis. West Nile virus is not transmitted directly from birds to humans or from person to person.

Medical care should be sought as soon as possible for people who have symptoms suggesting severe illness. There is no specific treatment for West Nile infection or vaccine to prevent it. Treatment of severe illnesses includes hospitalization, use of intravenous fluids and nutrition, respiratory support, prevention of secondary infections, and good nursing care.

Hunters should follow the usual precautions when handling wild animals. They should wear gloves when handling and cleaning animals to prevent blood exposure to bare hands and meat should be thoroughly cooked.

More information about West Nile virus, reporting dead birds, and free awareness campaign materials may be accessed on the DHSS web site at: www.dhss.mo.gov/WestNileVirus.