Source of mysterious bug bites still unconfirmed, Fairfax County health experts say

(Updated at 3:45 p.m.) Fairfax County residents are itching to understand the culprit behind weird skin reactions, possibly linked to bug bites, that have been reported throughout the D.C. region this summer.

As first reported by Reston Now’s sister site ARLnow, people in Northern Virginia and beyond are finding itchy red marks on their skin that are not quite mosquito bites and may be linked to oak leaf itch mites, an arachnid that’s nearly invisible to the naked eye.

Dr. Amir Bajoghli, a dermatologist who sees patients in McLean and Woodbridge in his Skin & Laser Dermatology offices, says he has seen an increase in the number of patients with this kind of issue, often involving raised red bumps or tiny blisters. The bumps can look like acne and be intensely itchy, similar to poison ivy.

“Because of all the cicadas we had, [the mites] were basically feasting on the eggs,” Bajoghli said, noting the mites can fall from the trees and be carried by wind. “Patients have even been telling me it’s worse than their experience with poison ivy.”

Oak leaf itch mites might cause red welts and affect people not only outdoors, but also indoors, potentially entering through window screens.

They typically feed on the larvae of small flies that form on leaves in oak trees. But local health officials suggest this year’s cicada emergence may be a factor, giving oak leaf itch mites another source of food from the cicada eggs laid in trees.

Still, Fairfax County health officials stressed that there’s no confirmation that the oak leaf itch mite is the cause of the bites, saying “it’s only a suspected cause at this time.”

“Although we are not certain what may be causing these bites, one of the suspected causes is the microscopic Oak Leaf Itch Mite,” Joshua Smith, the environmental health supervisor of the Fairfax County Health Department’s Disease Carrying Insect Program, said in a statement. “This mite has been presumptively associated with itchy bites in other regions of the U.S.”

States from Illinois to Texas have observed apparent outbreaks of the mite throughout recent decades.

“Most puzzling was the lack of any insect being seen or felt during the act of biting,” a research paper on a 2004 outbreak in Kansas noted.

Bajoghli, the dermatologist, recommends hydrocortisone as a starting point for treatment, which people can obtain without a prescription.

If that’s insufficient, doctors and dermatologists can provide prescription-strength remedies. He said over-the-counter antihistamines are also somewhat helpful.

“People can best protect themselves by limiting their time from under infested trees and by immediately removing and laundering clothing and then showering,” Penn State Extension researcher Steve Jacobs wrote in a patient-focused guide.

Whether the skin reactions involve that mite or something else, the Fairfax County Health Department has several recommendations for steps people can take to prevent problems with mosquitoes, ticks, and other pests:

• Use repellents. Products registered with the Environmental Protection Agency and recommended by the Centers for Disease Control and Prevention have active ingredients that include DEET, IR3535, picaridin, and more.
• Wear long pants and long-sleeve shirts outdoors.
• Shower after outdoor activities, washing away crawling ticks as well as doing a tick check.
• Launder clothes worn for outdoor activities. Ten minutes in the dryer on high heat will kill ticks on clothing.
• Avoid scratching bites. A cold compress or other products may help relieve itchiness.

People with questions and concerns are encouraged to talk with their health care provider.