Mosquito-borne diseases still a concern despite cooler fall weather
It’s fall, but continue to protect your kids against mosquito bites.
Outdoor play and camping are a tremendous health benefit for children to enjoy, but at the same time, parents can take measures to prevent mosquito bites.
Most people have become aware of Zika virus because of the seriousness of its effects on the developing fetus. However it is also important for West Virginians, especially those living in the southern and central part of the state, to be aware of another mosquito-borne disease which, although it does not affect babies in the womb, can cause central nervous system infections in children and adolescents. This infection is called La Crosse encephalitis, which is caused by a virus of the same name.
Over the past 15 years, there have been on average about 20 cases per year of this disease in West Virginia, mostly in those between 4 and 18 years of age, although rare cases in adults have occurred.
Most children have negligible or mild disease after exposure to the La Crosse virus from the bite of an infected mosquito, but some children go on to develop more severe disease. These children with more severe disease frequently have headache, fever and vomiting, and about half of these will progress to have seizures. A smaller percentage will have disorientation or even coma. Most children with the more severe type of disease will require admission to the intensive care unit.
Fortunately, this severe form of the disease is fairly rare, compared to the large number of people who are exposed and then have mild or even unapparent disease.
Nevertheless, when one considers La Crosse encephalitis, as well as the rare possibility of getting West Nile encephalitis, not to mention recent concerns about Zika, there are many good reasons for parents and individuals to protect their children and themselves from mosquito bites.
Before talking about mosquito repellents, it is quite important to take environmental steps to reduce places where mosquitoes can breed, especially in areas near your house or where children play.
The best step to take is to reduce areas of standing water, especially those which occur when small containers are left near the house, such as buckets or bird-baths, or even styrofoam cups or other trash which has not been properly discarded.
An especially serious problem is discarded tires, which readily trap and retain water. These are “disastrously good” breeding sites for mosquitoes to lay their eggs. Stopped-up gutters are also to be avoided for the same reason.
In places where standing water might be hard to drain, some of these areas might be amenable to the use of larvicide “dunks,” which are lethal to the mosquito larvae. As usual with such products, check labels as to proper use for best efficacy and safety.
Finally, on mosquito repellents, a Consumer Reports article from July 2015 found products with either picaridin or DEET to be effective, with the caveat that these should not be used on children under 2 months of age and should only be used at approved concentrations. Products with oil of lemon eucalyptus were also found to be effective, with the exception that these should not be used in children under 3 years of age.
Most of the available products using picaridin as the active ingredient provide it in a 20 percent concentration. DEET products approved for use in children should have concentrations in the range of 10 to 30 percent, per the recommendations of the American Academy of Pediatrics. Oil of Lemon Eucalyptus is mainly available in a 30 percent concentration.
All three of the above are considered safe and effective when used at the above concentrations in children and when used as directed by the accompanying label. Concentrations less than 10 percent for the above-mentioned ingredients were not found to be effective in the Consumer Reports article.
An important tip about application of insect repellents is that it should be used only on exposed skin, not under clothing. It should be not be sprayed directly on the face, but sprayed on the hands and then applied to the face, with avoidance of the eyes and mouth, as well as any wounds or irritated skin.
Other guidance should be carefully followed as directed by the product label.
Finally, a common-sense approach to reducing mosquito exposure is wearing hats, long-sleeve shirts, pants, etc., when weather permits, and this is the primary approach for babies below 2 months of age.
Mosquitoes will be with us until a good frost or two, which may be even into November, and, thus, parents are reminded that “the readiness is all” in protecting children from mosquito bites and reducing mosquitoes in the environment.
This story originally appeared as an op-ed in the Charleston Gazette-Mail by Dr. James McJunkin, MD. McJunkin is a professor of pediatric medicine and researcher at the West Virginia University Charleston Division.