Protection against mosquitos and concern about DEET

One mosquito bite and it seems we are exposed to an increasing host of bad stuff from malaria, West Nile and now the Zika virus. If that is not enough, Fido can end up with heart worms.

Is there any protection?

Yes. There is an effective repellent that has worked for 50 years on hundreds of millions of people with few, if any, side effects:

DEET.

Some still don't trust it.

Popular Science calls DEET the most effective mosquito repellent ever invented. But, like many chemical agents, DEET has come under suspicion in recent years, even though it has a long track record of safe use.

Developed by the US Agriculture Department in 1946, it was designed to protect soldiers. It has been available to the public since 1950. Hundreds of millions of people have used it safely since 1950. Today, it is applied 200 million times a year worldwide. Since its invention, it has literally been used billions of times, according to the Los Angeles Times.

So why the worries? The EPA says concerns are overblown, and DEET poses no health concern, especially when weighed against the dangers of mosquito-born illness.

As a practical precaution, DEET should be used when necessary and not excessively. It should be washed off the skin after use. It should not be sprayed under clothes, but is fine on top of clothing.

DEET has been implicated in a handful of deaths during a 20-year study period but never named as the cause. In all cases, the chemical was either deliberately ingested, or a heavy application was repeatedly applied to children.

In 1995, researchers reporting in the Journal of American Mosquito Control found 14 cases of individuals who had used DEET and suffered encephalopathy, a brain disease. All but one were under 8 years old. Three died. The others recovered. The researchers wrote that the exact role of DEET was difficult to determine. It could have been other factors, or it might have been DEET.

A 2001 study in the American Journal of Tropical Medicine and Hygiene concluded that DEET has no adverse effects on the growth and development of children in the womb or a year after birth. The authors concluded it was safe to use during the second and third trimesters of pregnancy.

In the European Union, the repellent is approved for only 15 percent strength. In the US, DEET is sold in concentrations of up to 30 percent. The EPA approves DEET for use on human skin at 100 percent concentration.