Vail doc: Fight the bite this summer
Vail, CO Colorado
I’m a Vail Valley resdient and I hate to use insect repellents – they smell and carry toxic chemicals. At the same time I am afraid of West Nile virus, for myself and my family. What should I do?
– Mosquito phobic in Avon
Dear Mosquito phobic,
First, you are not alone! Most of us hate those buzzing nuisances that seem to target us incessantly.
West Nile is an arbovirus to be exact. It was first identified in 1937 in Uganda – you guessed it, in the West Nile district. West Nile virus was recognized in Israel in 1957, in France in the 1960s and came to the U.S. in 1999. Best estimates are that it came via an infected bird to New York State. That same year, the first human case of West Nile virus in the U.S. was identified. It has adapted well to our country and by the summer of 2002, not only had it arrived in Colorado, but it actually reached California. It has been with us ever since, and likely is here to stay.
West Nile virus is transmitted by a mosquito bite, but not all mosquitoes carry the virus. Birds are the reservoir of infection. That is they carry the infection, which is then transmitted to some annoying mosquito that has nothing better to do than bite us. The transmission of the virus is unnoticed. That means the reaction to the bite has nothing to do with the process of becoming infected. Any person may have a significant reaction to a harmless bite or no reaction to a bite, which has infected them.
Several risk factors are important when it comes to being infected. The outside temperature makes a difference. The hotter it is, the more likely an infected mosquito can transmit the virus. For that reason, the risks of West Nile virus begin now and increase through August and early September. The types of mosquito that carry the virus are active from dusk to dawn, so that is the key time to focus on prevention by staying indoors or wearing appropriate clothing and insect repellent. So far this year only one human case of West Nile virus has been confirmed in the U.S. – in Hughes County, South Dakota. Now then is the time to begin our awareness, preparation and prevention.
How to prepare
1. If possible, eliminate any standing sources of water that might last for more than several days.
2. Know that infected mosquitoes are much more active at dawn and dusk.
3. Wear protective clothing when possible – long sleeves and long pants – during times of greatest activity.
4. Use an insect repellant.
5. DEET is the most effective insect repellant and can be used safely in adults and children older than 2 months. Use products containing 20 to 30 percent DEET for adults and 10 percent DEET for children.
Fortunately, symptoms are uncommon. A full 80 percent of people actually infected have no symptoms at all. That’s an important number. It doesn’t look at people exposed to mosquito bites; it looks at people actually infected by the virus. Of those who develop symptoms, 97 percent will be mild. Like many viruses, these may include the abrupt onset of fever, headache, sore throat, backache, muscle aches, fatigue and possibly vomiting and a rash. Only 0.6 percent of those infected or one person in 150 will develop more severe symptoms. These symptoms could include weakness, paralysis and meningitis or encephalitis (a spinal cord or brain infection). If you’re sick, but no worse than when you have a cold or the flu, rest, drink fluids, use Tylenol or ibuprofen for symptoms and call your doctor if you have questions or concerns. Anything worse and you should get checked! It is believed that you can get West Nile virus once and thereafter immunity lasts a lifetime.
Next week I’ll talk more about DEET and insect repellants.
For more information, visit http://www.fightthebitecolorado.com. I’ll keep you posted as West Nile virus spreads and inevitably hits our beautiful state. Be smart, don’t worry, “Fight the Bite” and have a great summer!
I also want to wish all the dads a happy belated Father’s Day!
Dr. Drew Werner is the vice chief of staff at Valley View Hospital in Glenwood Springs and the Eagle County Health Officer. He lives in Eagle with his family. E-mail comments about this column to firstname.lastname@example.org.
Warm weather means its sludge-treatment time and it’s been a big volume spring