Prevalence of trypanosome infections in dogs from Chagas disease endemic regions in Panama, Central America

The prevalence of canine trypanosomosis was investigated in two Chagas disease endemic rural communities located in the central region of Panama. Serologic tests for Trypanosoma cruzi infection revealed a prevalence of 11.1%. Hemocultures coupled with PCR analysis demonstrated a Trypanosoma rangeli infection rate of 5.1%. An overall trypanosome infection index of 16.2% (16/99) was detected in this canine population. One dog had a mixed infection of T. cruzi and T. rangeli. Six of the trypanosome-infected dogs belong to people who were diagnosed of Chagas disease. We conclude that dogs from this rural area of Panama are frequently infected with trypanosomes transmitted by the sylvatic vector, Rhodnius pallescens, and suggest that dogs are important in the peridomestic transmission cycle of trypanosomes as reservoirs and hosts. The epidemiological implications of these findings are discussed.