Fig. 33.—Schizotrypanum cruzi in blood of child with acute type of Brazilian trypanosomiasis. (MacNeal from Doflein after Chagas.)
In investigating the matter of the importance of this flagellate, Schizotrypanum cruzi, in Minas Geraes, Brazil, where the above-named bug was present in great numbers in the cracks of the houses of the poor he associated this flagellate infection, which he at first considered trypanosomal, with a disease of the children of that section.
The bug is a vicious feeder and, from its biting chiefly about the face, has been called barbeiro or barber by the natives. Both the male and female of Lamus bite and can transmit the disease and although the parasite is not transmitted hereditarily the nymph is capable of sucking blood and becoming infected.
Fig. 34.—Conorhinus megistus, the insect carrier of Schizotrypanum cruzi. (From Doflein after Chagas.)
It requires several months for the insect to go through the egg, larval and pupal stage to maturity. Some consider this bug to belong to the genus Triatoma. The insects may live for more than a year and tend to remain in the same house where they may have become infected but leave such house if it be abandoned by man. Brumpt thinks that the bedbug may also transmit the disease. A large proportion of armadillos in the endemic areas are infected with S. cruzi but do not seem to be affected thereby. It has been suggested that this animal may be a reservoir of virus.
Fig. 35.—Schizotrypanum cruzi developing in the tissues of the guinea pig. 1. Cross-section of a striated muscle fibre containing Schizotrypanum cruzi: Note dividing forms. 2. Section of brain showing a Schizotrypanum cyst within a neuroglia cell, containing chiefly flagellated forms. 3. Section through the supra-renal capsule, fascicular zone. 4. Section of brain showing a neuroglia cell filled with round forms of Schizotrypanum. (From Low, in Sleeping Sickness Bulletin, after Vianna.)