The Crawling Epidemic: Epidemiology

One of my first encounters with kissing bugs, vinchucas, was in the airport in Cochabamba, Bolivia, where I went to meet Benjamin Menesis, who had arrived from Sucre and was carrying a suitcase with over 1,000 specimens of the insect. Menesis was a technician for the Proyecto Británico Cardenal Maurer (PBCM), which was conducting a vinchuca ‑eradication program in the Department of Chuquisaca, Bolivia. An important part of this program at the University in Cochabamba was to determine the rate that vinchuca bugs became infected.

Staff had collected vinchucas from houses in Chuquisaca with flypaper and by means of a contest among schoolchildren to see who could bring the most vinchucas to school. Pupils thus realized how infested their homes were and received a lesson on Chagas’ disease. The director of PBCM, Ruth Sensano, stored the vinchucas in an ice chest. They became active in the dark box, being nocturnal creatures, and began a scratching sound clearly audible to anyone within twenty feet. When the box was opened and a lit flashlight placed inside, the vinchucas quieted down due to their photosensitive nature.

Menesis hand‑carried the freezer box onto the airplane in Sucre, refusing to put it in the hold where the cold might kill the vinchucas. He carried a radio to drown out chirping in flight with some loud music. Airport surveillance questioned Menesis about the chest, and he told them that he was carrying medical samples. Ruth Sensano convinced the inspector that Menesis needed to get the contents of the box to Cochabamba as quickly as possible for medical reasons. Menesis arrived without mishap in Cochabamba an hour later, and we joked about what could have happened if the box had come open inside the airplane and 1,000 vinchucaswere released, with over half of them carrying T. cruzi.

The vinchuca species most largely responsible for chagasic transmission in Bolivia is Triatoma infestans, which is relatively non‑aggressive and whose bite is more annoying than it is painful. Consequently, Bolivians do not refer to the insects as “assassin bugs,” as they are called in the U.S., but as “vinchucas, ” from the Quechua word huinchicuy, which means something that falls rapidly, because they glide down from the rafters, and as “kissing bugs,” because they prefer to suck blood from the faceoften from the lips and from near the eyes. Although Triatoma infestans has thus avoided the name “assassin bug” for the more benign name “kissing bug,” there is the subtle irony that the “kiss” of the bug can lead to death.