The bug that administers the kiss of death

TORONTO - A bug crawls onto your lips while you sleep, numbs your skin, bites and gorges on your blood. And if that’s not insult enough, it promptly defecates on the wound - and passes on a potentially deadly disease, called the Chagas’ disease.

Now Jean-Paul Paluzzi, doctoral candidate in biology at the University of Toronto, Mississauga, believes that manipulating physiology to prevent the insects from leaving their mess represents the best hope for stopping the transmission of Chagas’ disease.

“This is a disease of the poor,” says Paluzzi, who has visited parts of the world, affected by the illness. “The bugs are found in makeshift homes with mud walls and palm tree-like ceilings.

“Given that there are roughly 15 to 19 million people that are infected, a substantial proportion of that area’s population, it’s a disease that has been neglected,” adds Paluzzi.

Chagas’ disease is one of the major health problems in South and Central America and is spread by reduviid bugs, also known as “kissing bugs” because of their fondness for lips. Thery are drawn by the exhaled carbon dioxide.

The disease they transmit is caused by Trypanosoma cruzi, a parasite that lives in their gut. In the initial acute stage, symptoms are relatively mild, but as the disease progresses over several years, serious chronic symptoms can appear such as heart disease and malformation of the intestines.

To make matters worse, kissing bugs are particularly “bloodthirsty”. In mosquitoes, which go through four distinct stages of development, only adult females feed on blood (and potentially transmit disease).

This means that pest control methods need to target only one out of eight stages (when you include both sexes), said a University of Toronto release.

But in kissing bugs, each sex feeds on blood through all fives stages of development. “So you have about a 10-fold greater chance of infection just because of the number of times that these insects have to feed,” says Paluzzi.