Analysis of Infection of Trypanosoma cruzi, Causative Agent of Chagas Disease, in

Triatomine Insects from Southern Arizona

Acknowledgements: Teresa Gregory, Carolina

Reisenman, John Hildebrand

NASA Space Grant Symposium

April 18, 2009

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Traditionally confined to Latin America, but is becoming an increasing health risk in the U.S.

Neither a vaccine nor an effective treatment exist

Control of disease depends mainly on the control of vectors

CHAGAS DISEASECHAGAS DISEASE

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Parasite responsible for Chagas disease

Infective form (metacyclic trypomastigotes) resides in the rear gut of vectorial insects

Transforms into amastigotes after being transmitted to a mammalian host’s cells

TRYPANOSOMA CRUZITRYPANOSOMA CRUZI

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T. CRUZI LIFE CYCLET. CRUZI LIFE CYCLE

Vector stage

Host stage

Photo courtesy of Chip Hedgcock

Primary potential vector of T. cruzi

Prevalent species: Triatoma rubida, Triatoma protracta, and Triatoma recurva

Feed on the blood of warm-blooded vertebrates (tend to bite near their victim’s mouth)

During feeding, the parasite is displaced onto the mammal host through defecation

The parasite then enters the open wound and infects the mammal host

THE KISSING BUGTHE KISSING BUG

GOAL OF PROJECTGOAL OF PROJECT

Determine if triatomine insects in the greater Tucson area are infected with Trypanosoma cruzi determine their vectorial capacity

Perform a demographic analysis between infected insects, location found, and other important variables

Develop preventative measures to reduce the potential risk of transmission of T. cruzi

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METHODSMETHODS

Kissing bugs from the 2006 season that tested positive for T. cruzi infection have been sent to

the CDC and are presently being confirmed

Work on the 2007 & 2008 season is currently underway

Kissing bugs for the 2009 season will begin being collected at the end of the month

RESULTSRESULTS

Develop preventative measuresoTraps incorporating carbon

dioxide, heat, or light

Behavioral studieso Patterns of defecation

CONCLUSIONSCONCLUSIONS

FURTHER FURTHER DIRECTIONSDIRECTIONS

A complete demographic analysis will aid in reducing the public

health risk

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THANK THANK YOUYOU

SYMPTOMS OF CHAGAS SYMPTOMS OF CHAGAS DISEASEDISEASE

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• Redness and swelling at the site of infection• Fever • Fatigue • Body aches • Nausea, diarrhea or

vomiting • Swollen glands

(10-20 years later)

• Irregular heartbeat • Inflamed, enlarged heart (cardiomyopathy) • Congestive heart failure • Enlarged esophagus and colon

TRANSMISSIONTRANSMISSION

Infection by insect vector• Only 6 such human cases in the United States

Transfusion by contaminated blood •In 2007, the FDA licensed an assay allowing blood donors to be easily screened for T. cruzi

Mother to child (congenital)