With 241 cases of West Nile virus and four related deaths reported so far this year, the United States is experiencing the biggest spike in the mosquito-borne illness since 2004, health officials report.
As of August 1, Texas has confirmed 111 human cases of West Nile and three deaths.
Mississippi and Oklahoma are also seeing earlier activity than usual. Overall, 42 states had detected West Nile virus infections in people, birds or mosquitoes as of July 31, the U.S. Centers for Disease Control and Prevention said Wednesday.
"It is not clear why we are seeing more activity than in recent years," Dr. Marc Fischer, medical epidemiologist with agency's Arboviral Diseases Branch, said in a CDC news release. "Regardless of the reasons for the increase, people should be aware of the West Nile virus activity in their area and take action to protect themselves and their family."
Typically, the greatest risk for infection with West Nile virus occurs from June through September, with cases peaking in mid-August. But changes in the weather, the number of infected mosquitoes and human behavior can all influence when and where outbreaks of the virus occur, the CDC noted.
So what can you do to protect your family against the potentially deadly virus?
The CDC recommends:
- Use insect repellents when outside.
- Wear shoes, long sleeves and pants at dawn and dusk.
- Install or repair window and door screens.
- Use air-conditioning whenever possible.
- Do not leave standing water outside in open containers, such as flowerpots, buckets and kiddie pools.
Other suggestions include:
- Have clogged roof gutters cleaned every year, particularly if the leaves from surrounding trees have a tendency to plug up the drains. Roof gutters can produce millions of mosquitoes each season.
- Aerate ornamental pools or stock them with fish. Water gardens can become major mosquito producers if they are allowed to stagnate. Clean and chlorinate swimming pools not in use. A swimming pool left untended by a family on vacation for a month can produce enough mosquitoes to result in neighborhood-wide complaints. Mosquitoes may even breed in the water that collects on pool covers.
Symptoms of the West Nile virus can be similar to a cold. People can have a fever, headache, body aches, joint pains, vomiting, diarrhea or rash. In more extreme cases, the virus can lead to serious a neurological illness, such as encephalitis or meningitis (inflammation of the brain or surrounding tissues), or even death.
People older than 50 and those with certain medical conditions, such as cancer, diabetes, hypertension, kidney disease and organ transplants, are at greater risk for serious illness.
Although most people with mild cases of West Nile virus will recover on their own, the CDC recommends that anyone who develops symptoms of the illness should see their doctor right away.
When healthy children are infected with the West Nile virus, they usually develop mild symptoms, but children with any immune system disorder can develop more serious complications.
You cannot catch West Nile virus from an infected playmate or from touching or kissing a person who is infected. The virus is spread mostly through mosquito bites.
DEET is an effective insect repellent but requires special attention when it is used on children or people with a sensitivity to the product.
- The concentrations of DEET vary significantly from product to product ranging from less than 10 percent to over 30 percent so be sure to read the label before you buy. The higher the concentration of DEET, the longer the action and the greater the effectiveness of the product. Effectiveness peaks at 30 percent, which is also the maximum concentration recommended for children. Check the label for this percentage because some products can have concentrations much higher than 30 percent. DEETs safety does not appear to be related to its level of concentration, however; a prudent approach is to select the lowest effective concentration for the amount of time your child spends outdoors.
- Avoid products that include DEET in a sunscreen because the sunscreen needs to be applied frequently, while the DEET should be used just once a day. More frequent applications of DEET may be associated with toxicity. Also be sure to wash the DEET off with soap and water at the end of the day. Even older children should not apply DEET- containing repellents more than once a day.
- Do not use DEET preparations on infants under two months of age. In older children, apply it sparingly around the ears, and don't use it on the mouth or the eyes. Don't put it over cuts.
An alternative to DEET, called Picaridin, has had wider use in Europe, but has recently been marketed for use in the United States. It is a pleasant-smelling product without the oily residue of DEET. It is used in concentrations of 5 to 10 percent.
Many states are going street-to-street, spraying insect repellent at night in high-risk neighborhoods. Make sure your child remains inside during spraying and never allow your child to run behind a spray truck.
Mid-August is the peak time for spreading the virus. Staying alert about standing water and using protective clothing and insect repellent during dawn and dusk will go a long way in protecting your family from the West Nile virus.