Several national news networks reported yesterday that a kissing bug had been found in Delaware. The story was echoed today by a number of print and online news outlets. Frankly, the story is much ado about nothing.
Story details varied. However, apparently, a Delaware family had contacted the Delaware Division of Public Health (DPH) and the Delaware Department of Agriculture (DDA) in July 2018 for help in identifying an insect they alleged had bitten their daughter as she was watching TV. The DDA identified the suspect as Triatoma sanguisuga and contacted the Centers for Disease Control and Prevention (CDCP) for a confirmation. The CDCP released its finding last Friday (April 19, 2019) which appears to have sparked the news media brouhaha.
An Evocative Envoy
Kissing bugs have become an evocative envoy for entomophobia in recent years. Bug hysteria swept through Ohio as well as several other states in 2015 owing to wheel bugs (Arilus cristatus) being misidentified as kissing bugs. Granted, with their long spindly legs, large bodies, narrow heads with beady eyes; they both may appear a bit scary to the uninitiated.
Even common names can sound scary. The descriptive common name for Triatoma sanguisuga is the Bloodsucking Conenose. Thankfully, none of the news media reports included this name!
The bug uses its piercing-sucking mouthparts attached to a cone-shaped nose-like structure at the front of its head to bite and suck blood; thus the common name. Its lifestyle is further emphasized by the specific epithet: "sanguisuga" means "bloodsucker."
The awareness that kissing bugs can spread Chagas Disease is also scary. However, the chance that such a thing could happen in Delaware or Ohio is negligible.
Just the Facts
There are several species of bugs belonging to the Triatoma genus that are collectively known as "kissing bugs" because they tend to bite near a person's mouth. These "triatomine bugs" get away with their cheeky behavior by biting people while they sleep.
The bites are usually painless but may lead to a serious disease if the bugs are harboring the protozoan Trypanosoma cruzi in their gut. The bugs don't inject the protozoan when they bite; they release it from their other end when they defecate. Infection occurs only if the protozoan is accidentally rubbed into the bug's feeding wounds or onto mucous membranes such as nasal passages. The resulting Chagas disease is nothing to sneeze at; it can be deadly.
However, people living in Ohio or Delaware shouldn't lose sleep over contracting Chagas disease unless they travel to more southern climes. The highest occurrences of the disease is in Mexico as well as Central and South America where the bugs may encounter large concentrations of people and other mammals that could be harboring the protozoan.
A number of the news stories showed pictures of the bloodsucking conenose and implied the bug recently arrived from South or Central America. This isn't true: it's already here. According to a paper published in the Ohio Journal of Science in 1960 titled, "Arthropods of Medical Importance in Ohio," the bloodsucking conenose is found in southern Ohio (see More Information below). The bug primarily feeds on small mammals living in forested areas.
In fact, I found and photographed the bloodsucking conenose bugs appearing in this Alert in the Greater Cincinnati area; specifically Butler and Hamilton counties. Although rare, they appear to be endemic to the region. The same is probably true for Delaware. Keep in mind that a new find, or new state record for an insect, does not necessarily mean the insect spread into that state. It may simply reflect the rarity of the insect in that state.
More importantly, finding the bloodsucking conenose in Ohio, or Delaware, does not mean our citizens are at risk for Chagas disease for two reasons:
1. Contracting Chagas disease requires more than just coming into contact with a kissing bug, or even being bitten by a kissing bug. The bug must be carrying the protozoan. This is highly unlikely given the rarity of the bloodsucking conenose in Ohio, and probably Delaware, coupled with the extremely low probability the bug will acquire the protozoan by feeding on an infected person or other mammals.
2. Infection only occurs if a bug carrying the protozoan defecates while feeding. Research has shown that the bloodsucking conenose rarely defecates on its host. In fact, Triatoma sanguisuga is not considered a major vector of the protozoan even where Chagas disease is common in South and Central America. One of the primary vectors in that part of the world is T. infestans which goes by the common name, vinchuca. Unfortunately, this bug is also sometimes called the "bloodsucking conenose" which may create confusion and illustrates the importance of using scientific names!