“Mystery bites” plague a significant number of people. Unfortunately, there can be a range of causes, most of which do not involve insects. The frustration of invisible itches can cause significant stress and anxiety. Even when they are insect-related, it can be very difficult to capture a culprit. Consequently, many complaints go unresolved.
Above-normal rains this summer have created many wet breeding sites for tiny blood-feeding gnats called “no-see-ums” by some. These minute insects can approach a person, bite, and leave without being detected. Individual reactions to their bites can range from small red welts to local allergic reactions that itch intensely. Patient and persistent work by the victims and agents in Daviess and Todd counties have resulted in identification of these insects in two cases.
Identifying the cause of a problem is significant but in some cases there is no effective course of action to remedy it. Several species of these biting gnats and their larvae develop in a range of aquatic and semi-aquatic or marshy sites that are impossible to find, eliminate, or treat, even though they probably are nearby. Repellents may provide some relief, but a killing frost is the only thing that holds real promise for ending the problem.
By Lee Townsend, Extension Entomologist