cruzi Transmission

Abstract

Chagas disease, an infection with the parasite Trypanosoma cruzi, is increasingly diagnosed among humans in the southern United States. We assessed exposure of shelter dogs in Texas to T. cruzi; seroprevalence across diverse ecoregions was 8.8%. Canine serosurveillance is a useful tool for public health risk assessment. The protozoan parasite Trypanosoma cruzi is the causative agent of Chagas disease, a neglected tropical disease affecting>8 million persons across Mexico and Central and South America. In the United States, estimates of human infection range from 300,000 to>1 million (1,2). Although immigrants exposed in Chagas disease-endemic regions constitute the majority of infected persons in the United States, autochthonous transmission is increasingly recognized (3), and enzootic cycles involving infected wildlife reservoirs and domestic dogs occur across the southern United States. (4). Vectorborne transmission occurs through contamination of the bite site or mucous membranes with feces of infected hematophagous triatomines (“kissing bugs”). In addition, the parasite can be passed through consumption of infected bugs or contaminated food products, through blood transfusions, and congenitally (4). Clinical manifestation in humans and dogs ranges from asymptomatic to acute myocarditis and sudden death to chronic progressive cardiac disease (5,6). No vaccine is available for humans or dogs. Drugs used to treat Chagas disease in humans have not been approved by the US Food and Drug Administration and are available in the United States only through investigational protocols. The disease is notifiable in 4 states including Texas, where as of 2013, human and veterinary cases must be reported. Texas is a high-risk state for transmission of T. cruzi to dogs, considering the diversity of triatomine vectors, reservoir hosts, and previous documentation of canine disease (5,7). Because dogs arriving at shelters may have hig