History

The history of the discovery of T. Cruzi: Hail Carlos Chagas!

A Brazilian medical student, Carlos Chagas (age 29), discovered T. cruzi in 1910 in its insect vector, the reduviid bug Panstronglyus megistus.  Chagas had been sent to work on an antimalarial campaign on a railroad construction line by Oswaldo Cruz (who the parasite T. cruzi would later be named for), the director of his medical school in Rio de Janeiro.  

The Great Carlos Chagas (1879-1934) - He discovered the T. cruzi parasite, its insect vector and the reservoir host! (left) The reduviid, aka 'kissing,' aka assasin bug! (right)

http://www.epub.org.br/gastro/n0202/historia.htm (Chagas) http://www.unc.edu/~meade/geog134/projects/centralam/vector.html (reduviid)

After finding the parasite in the vector and a cat, Chagas saw a 2-year-old patient with an enlarged spleen and liver.  He performed a blood test and found that she had trypanosomes in her blood that looked like those he had found in the cat. 

One year later a railroad worker told Chagas about the “kissing bugs” that sucked blood from sleeping people’s faces.  Chagas hypothesized  that this bug could be spreading disease to humans and animals so he looked at the hindgut of the kissing bug and found parasites that looked just like the trypanosomes he had found in the cat and the little girl.  The bugs were sent to a lab in Rio where they fed on monkeys and it was shown that they spread the T. cruzi parasite.  In 1912 Chagas discovered that the reservoir host was the armadillo.

References:

http://martin.parasitology.mcgill.ca/jimspage/biol/tcruzi.htm

Voge and Markell, 134