Infectious Disease Compendium

Trypanosoma

Microbiology

A protozoa; Trypanosoma brucei subs. gambiense, Trypanosoma brucei subs. rhodesiense and Trypanosoma cruzi.

One case of T. evansi in Vietnam from slaughtering cows.

Epidemiologic Risks

Trypanosoma brucei subs. gambiense: bit by a tsetse fly in W. Africa.

Trypanosoma brucei subs. rhodesiense: bit by a tsetse fly in E. Africa.

Trypanosoma cruzi: bit by a blood sucking triatomine insects, or kissing bugs in S. America. Many animals serve as a reservoir. There was an outbreak due to drinking contaminated fresh guava juice (PubMed).  And perhaps bed bugs (PubMed).

Curiously, in Arizona, 41.5% of triatomines (the vector of Chaga's) were infected with T. cruzi (PubMed). However, the bugs in Arizona do not feed on humans. It turns out the US South is rife with Chagas and they are feeding on humans, indoor and out (PubMed). It has been spread in S. California (PubMed).

Chagas is spread when the triatomine feeds and at the same time takes a crap. The human then itches, driving the bug crap into the skin also with the Chaga's. In the US the triatomine is more fastidious, leaving its feeding site before taking a crap. Perhaps this is why there is less Chaga's in the US.

In Texas, one in 6,500 tested positive for the Chagas, much higher than the usual one in 300,000 of the CDC. So there may be more Chaga's in th US than we are aware. And reports of disease in Texas go back to 1935 (PubMed).

The rates in those born south of the border in LA are 1.24% with different countries of origin at different risks (PubMed).

Since the fall of 2014 serology is done as part of blood donation, so expect the occasional case. The CDC will assist in confirmation serology as well as acquiring medications.

Syndromes

Trypanosoma brucei subs. gambiense: Sleeping Sickness; a more chronic illness of months duration with CNS findings late in the course of the disease.It causes chronic illness by changing its outer cell glycoprotein.

Trypanosoma brucei subs. rhodesiense: Sleeping Sickness a more acute illness with CNS finding early.

Trypanosoma cruzi: Chagas.

Early: local swelling in the area of the bite, often around the eye.

Late: a disseminated disease that presents with cardiomyopathy, esophageal and megacolon. It likes to live in macrophages, where it finds a safe harbor.

Treatment

Trypanosoma brucei subs. gambiense:

Trypanosoma brucei subs. rhodesiense:

Trypanosoma cruzi: acute: Nifurtimox is 8 to 10 mg/kg/day. Nothing works for chronic disease, although benznidazole in adults at 5 to 7.5 mg per kilogram of body weight q day, for 60 days looks promising (PubMed)

Since the fall of 2014 serology is done as part of blood donation, so expect the occasional case. The CDC will assist in confirmation serology as well as acquiring medications.

Call the Parasitic Diseases Public Inquiries Line (770-488-7775; parasites@cdc.gov; www.cdc.gov/parasites/chagas), the CDC Drug Service (404-639-3670).

Notes