Endemic in 21 countries across Latin America, Chagas disease kills more people in the region each year than any other parasite-born disease. We targeted the Triatomine bugs that transmit Chagas disease as a test vector for the Virtual Vector Laboratory species identification system. 

Triatomine bugs feed on people and other animals while they are sleeping thereby contracting and transmitting the Trypanosoma cruzi parasite that causes Chagas disease between humans and other mammals.

Triatomine bugs feed on people and other animals while they are sleeping thereby contracting and transmitting the Trypanosoma cruzi parasite that causes Chagas disease between humans and other mammals.

Above left: Triatomine bugs regularly defecate after taking a blood meal from a sleeping host (dark spot on skin). Above right: Microscopic image of Trypanosoma cruzi parasite with red blood cells. Bottom right: The dermal presentation of a bite that has become infected by the parasite.

Above left: Triatomine bugs regularly defecate after taking a blood meal from a sleeping host (dark spot on skin). Above right: Microscopic image of Trypanosoma cruzi parasite with red blood cells. Bottom right: The dermal presentation of a bite that has become infected by the parasite.

The 150 different species of Triatomines have a variety of habits and ecological niches and are found in both rural and urban settings. There is little to stop them from entering this traditional Mayan home for a blood meal while the homeowners are sleeping. Thatched roofs make great places for them to hide during the day.

The 150 different species of Triatomines have a variety of habits and ecological niches and are found in both rural and urban settings. There is little to stop them from entering this traditional Mayan home for a blood meal while the homeowners are sleeping. Thatched roofs make great places for them to hide during the day.

In wild and domestic settings

Some species of Triatomines are primarily "sylvan" or live in the wild while others are much more accustomed to nesting and breeding inside peoples homes. Whether sylvan or domestic, when night falls they can find their way to where people are sleeping through their attraction to chemical signals and heat (like many insects they are also drawn to lights). After locating a host they will feed for approximately 10 minutes until they are engorged and then will frequently defecate on the bite site. If the bug is infected with the Trypanosoma cruzi parasite it will be present in the feces. Once on the skin it can easily enter the blood stream through the small bite wound or, if bitten on the face, through the mouth or eye.

CDC vector distribution map showing Triatomine locations in the United States

CDC vector distribution map showing Triatomine locations in the United States

no borders for bugs

Historically associated with Latin America, the range of some species of Triatomines that can transmit Chagas disease has expanded to include the Southern half of the United States. Bugs don't pay attention to borders and as climate change regularly disrupts "normal" habitats and opportunistic bugs hitch rides on vehicles, fly and walk where they please, the need for highly accurate maps of their range increases. In the United States, 24 species of wild mammals have been discovered to be infected with the T. cruzi parasite and it has been recently established that Americans are being infected by exposure to the bugs that feed on these mammals and then convey the parasite to humans.

Current conditions

It is estimated that in the American region nearly 100 million people are at risk of contracting the disease, and about 8 million are already infected. More than 95% of those already infected have never had access to diagnosis, let alone treatment. The Virtual Vector Laboratory has the potential to  identify and map the distribution of every species of Triatomine bug with unprecedented detail and become a key element in dramatically increasing awareness and reducing the rate of infection.

We currently know the most basic extent of Triatomine distribution in the Americas but can't accurately track species movement or the effects of eradication efforts.

Chronic disease

Chagas disease is one of the most neglected and destructive diseases largely because it is chronic and tends to slowly debilitate patients over a period of many years. Since those who are infected don't fall severely ill right away, as one would when infected with an acute disease, they often never know they are sick and may not get diagnosed (many doctors don't know to test for Chagas). Even if they do eventually get diagnosed it often isn't until irreversible damage has been done to their heart. This lack of early treatment leads to a steady weakening of the patient and a loss of ability to be active or maintain a much needed job. One of the most insidious ways that Chagas is economically destructive to a family is when an adult becomes chronically ill and can no longer work. In this common scenario the illness reduces the patient from being a provider to a financial burden and this can be especially devastating in lower income households.