Triatomine bugs are exclusively blood sucking insects that occur in Latin and Central America. They also occur to certain degree other parts of the world (especially in tropical and subtropical regions) (reference) and in the United States (reference). Both male and female are obligate hematophagous and are responsible for the transmission of American trypanosomiasis also known as Chagas disease, a major disease in Central and Latin America.
Triatomine bugs have adapted to living in and around houses making human their principal host for acquiring blood meal. They are obligate blood feeders, and females require the nutrient from blood for the maturation of their eggs. They also known as kissing bug because they prefer to bite on human faces while they are sleeping. Despite tremendous progress in the fight against triatomine bugs and the interruption of the disease transmission, Chagas disease is still prevalent in certain countries. There is currently no vaccine for the prevention of Chagas disease and the only alternative rely on the control of the bug.
Classification and Importance
Triatomine bugs belong to the order Hemiptera, family Reduviidae and subfamily Triatominae. They represent along with bed bugs (family Cimicidae), the two important groups of Hemipterans that have medical importance. The subfamily Triatominae contains 118 species species in the world classified into 5 tribes and 17 genera. Of these, only two of them, the Triatomini and the Rhodniini are important from a medical stand point.
The vectorial competence of triatomine bugs depend on the species and the geographical location. Globally, there are more6 species of triatomine, most of which occur in the New World. Other species have have been found in India Southeast Asia and Africa. Within the Triatominae, there are several species that are competent vector of various Trypanosoma species. In Latine America various names are used to designated triatomine bugs including, chinches, pitos, barbeiros, vinchucas.
For the Entomological Society of America, the name kissing bug is used as common name for the triatomine bugs (reference) (www.esa.org/commonnames). Rhodnius prolixus is prevalent Central America and and Latin American countries particularly in Venezuela and Columbia (reference). Triatoma infestans, a major vector of Chagas disease prefers to hide in roofs made of woods as well as in the soil (reference).
Morphology of triatomine bugs
Triatomine bugs have various coloration ranging from black to dark black often with yellow or orange patterns. There is also great variation in their size which range from 5 to 45 mm in general. Their abdomen have 11 segments which often serve as element of distinction between male and females. Females of triatomine bugs are generally larger than male and can be distinguished more precisely through their genitalia.
Mouthparts of Kissing bugs
As all all hemipteran insects, kissing bugs have piercing and sucking mouthparts that enable them to feed on a wide variety of fluids.
Bio-ecology of Triatomine Bug
Medical and Veterinary Significance of Triatomine Bugs
Triatomine bugs are obligate blood feeders and thus expose their hosts to the possibility of infection by microorganisms. Although biting of human skin is rarely painful (reference), itching may occur in certain cases (reference). Triatomine bugs are responsible for the transmission of American trypanosomiasis or Chagas disease to humans in Central and South America. The causative agent is a protozoan, Trypanosoma cruzi that is transmitted to human through the feces of the bugs. The vector competence of triatomine bug is dependent on the species and the geographical location (reference). Chagas disease is often associated with poverty, because it is more prevalent in rural areas with poor living conditions. Learn more about American Trypanosomiasis (chagas disease).
Chagas disease is not of medical importance in the United States as infection are rarely reported (reference).
Prevention and Control Strategies
Control and prevention of Triatomine bugs and Chagas disease aim at reducing or elimination the contact between humans and these bugs. Residual insecticides have been used in houses to eliminate kissing bugs. Their use is still warranted to prevent the establishment of kissing bugs in habitations.