Rapid detection of human blood in triatomines (kissing bugs) utilizing a lateral flow immunochromatographic assay - A pilot study

Abstract

BACKGROUND DNA-and proteomics-based techniques are currently used to identify a triatomine human blood meal. These methods are time consuming, require access to laboratories with sophisticated equipment, and trained personnel. OBJECTIVES We tested a rapid and specific immunochromatographic assay (that detects human blood in forensic samples) to determine if human blood was present in triatomines and their fecal excreta. METHODS We fed Triatoma rubida human blood (positive control) or mouse blood (negative control) and performed the assay on the abdominal contents and fecal excreta. Triatomine field specimens collected in and around human habitations and excreta were also tested. FINDINGS The assay was positive in triatomines fed human blood (N = 5/5) and fecal excreta from bugs known to have ingested human blood (N = 5/5). Bugs feeding on mice (N = 15/15) and their fecal excreta (N = 8/8) were negative for human blood. Human blood was detected in 47% (N = 23/49) triatomines, representing six different species, collected in the field. MAIN CONCLUSIONS The pilot study shows that this rapid and specific test may have applications in triatomine research. Further study is needed to determine the sensitivity of this assay compared to other well-established techniques, such as DNA-and proteomics-based methodologies and the assay's application in the field.

Vector mapping and bloodmeal metabarcoding demonstrate risk of urban Chagas disease transmission in Caracas, Venezuela

“…Importantly, however, bloodmeals on human hosts were detected far more often than those on common synanthropic animals such as mice/rats (identified in three pools), pigeons (one pool), or dogs (not detected). While very prominent, multiple observation of human blood feeding is not unexpected; similar has been reported from various less urban environments where human density relative to that of other animals is lower than in the MDC [69,72,73]. This study's bloodmeal analysis also specifically addressed domiciliary triatomines found in a visually blooded state.…”

Autochthonous Chagas Disease in the United States: How Are People Getting Infected?

“…1,[12][13][14][15] Human blood is also found in triatomines either collected in the field or around the home. [16][17][18] Kissing bug bites can be allergenic, leading to significant cutaneous reactions, and sometimes, life-threatening anaphylaxis (at least one death in Arizona). 19,20 The manifestations of a bite can also mimic an actual chagoma (e.g., Romana's sign; when the parasite enters the mucous membranes after a bite on the face).…”