A five-year domiciliary collection in the 22 departments of Guatemala showed that out of 4,128 triatomines collected, 1,675 were Triatoma dimidiata
(Latreille, 1811), 2,344 were Rhodnius prolixus
Stal 1859, and only 109 were T. nitida
Usinger 1939. The Chagas disease parasite, Trypanosoma cruzi
, was found in all three species. Their natural infection rates were similar in the first two species (20.6%; 19.1%) and slightly lower in T. nitida
(13.8%). However there was no significant difference in the infection rates in the three species (p = 0.131). T. dimidiata
males have higher infection rates than females (p = 0.030), whereas for R. prolixus
there is no difference in infection rates between males and females (p = 0.114).
The sex ratios for all three species were significantly skewed. More males than females were found inside houses for T. dimidiata
(p < 0.0001) and T. nitida
(p = 0.011); a different pattern was seen for R. prolixus
(p = 0.037) where more females were found. Sex ratio is proposed as an index to show the mobility of T. dimidiata
in different populations.
is widely distributed in the country, and is also the main vector in at least ten departments, but R. prolixus
with higher vectorial capacity is an important vector in at least two departments.