Oral Chagas Disease in Colombia-Confirmed and Suspected Routes of Transmission

Abstract

Chagas disease (CD) remains endemic throughout many regions of Colombia despite implementing decades of vector control strategies in several departments. Some regions have had a significant decrease in vectorial transmission, but the oral ingestion of Trypanosoma cruzi through consumption of contaminated food and drink products is increasingly described. This form of transmission has important public health relevance in Colombia due to an increase in reported acute CD cases and clinical manifestations that often lead to significant morbidity and mortality. Oral CD in Colombia has been associated with the consumption of contaminated fruit juices, such as palm wine, sugar cane, or tangerine juice and water for consumption, or contaminated surfaces where food has been prepared. Another interesting route of oral transmission includes ingestion of unbeknownst infected armadillos' blood, which is related to a traditional medicine practice in Colombia. Some earlier reports have also implemented consumption of infected bush meat as a source, but this is still being debated. Within the Amazon Basin, oral transmission is now considered the principal cause of acute CD in these regions. Furthermore, new cases of acute CD are now being seen in departments where CD has not been documented, and triatomine vectors are not naturally found, thus raising suspicion for oral transmission. The oral CD could also be considered a food-borne zoonosis, and odoriferous didelphid secretions have been implemented in contaminating the human dwelling environment, increasing the risk of consumption of infectious metacyclic trypomastigotes. In this article, we will discuss the complex transmission dynamics of oral CD in Colombia and further examine the unique clinical manifestations of this route of infection. New insights into the oral transmission of Trypanosoma cruzi are being discovered in Colombia, which can help bring increased awareness and a better understanding of this neglected tropical disease to reduce the burden of CD throughout Latin America.

Keywords: Chagas disease; Didelphis marsupialis; Panstrongylus geniculatus; Trypanosoma cruzi; armadillo blood; oral transmission; vector-borne zoonosis.

Figure 1

Confirmed (black arrow) and proposed (dotted black arrow) sources of oral transmission of Chagas disease in Colombia.

Figure 2

Countries in South America (left) where oral Chagas disease has been described and cumulative cases as documented in Colombia (right) where outbreaks have been reported to Instituto Nacional De Salud (INS).

Figure 3

(A) Two adult triatomines were found inside a home in the city of Liborina (Antioquia Department). (B) Both triatomines were identified as adult male Panstrongylus geniculatus using morphologic keys [101]. Trypanosoma cruzi DTU TcI was detected in one of the triatomines via RT-PCR molecular techniques [97].

Figure 4

(A) Home in Liborina, Antioquia, Colombia, where several adult Panstrongylus geniculatus triatomines were found by homeowner inside on the second floor. The homeowners commonly left their windows open with no screens, and (B) domesticated pigs were housed below the structure. (C) Debris was located adjacent to the building, where evidence of small rodents could be seen.

Figure 5

(A) Field trapping for Didelphis marsupialis in Miraflores, Boyacá Department, Colombia, near human dwellings and where suspected oral Chagas disease cases have been isolated. (B) Didelphis marsupialis found resting within canopy in Miraflores. (C) Female Didelphis marsupialis captured and anesthetized for T. cruzi infection testing. (D) Joeys were present in the marsupium, and concerns for vertical transmission of T. cruzi among Didelphis marsupialis are being investigated.