Exploring the diversity of blood-sucking Diptera in caves of Central Africa

Abstract

Caves house pathogenic microorganisms, some of which are transmitted by blood-sucking arthropods. In Africa, previous studies identified mosquitoes, sand flies and biting midges as the main potential vectors of cave-dwelling pathogens. However, to understand their involvement in pathogen spillover, it is crucial to characterize their diversity, community composition and dynamics. Using CDC light traps, we collected hematophagous Diptera in six caves of Gabon during one-shot or longitudinal sampling, and investigated their species diversity and dynamics in relation with external rainfall. Overall, we identified 68 species of mosquitoes, sand flies and biting midges, including 45 new records for Gabon. The dominant species were: Uranotaenia nigromaculata, Anopheles smithii s.l., Culex. rima group and Culex quasiguiarti for mosquitoes, Spelaeophlebotomus gigas and Spelaeomyia emilii for sand flies and the Culicoides trifasciellus group and Culicoides fulvithorax for biting midges. The survey revealed that species assemblages were cave-specific and included mainly troglophilous and trogloxenous species. Both diversity and abundance varied according to the cave and sampling time, and were significantly associated with rainfall. These associations were modulated by the cave specific environmental conditions. Moreover, the presence of trogloxenous and troglophilous species could be of high significance for pathogen transfers between cave and epigeous hosts, including humans.

Bat Flies and Their Microparasites: Current Knowledge and Distribution

“…Our knowledge of the microparasites of bat flies is strongly biased by sampling effort, which may also strongly reflect the currently known geographical distribution patterns of these parasites. We suggest to balance these biases by increasing sampling effort in less prospected countries as well as areas where human exposure to pathogen transmission is more likely to occur, due to cultural or touristic reasons (e.g., visiting caves) (15, 142). Additionally, we have little knowledge on the microparasites of other bat ectoparasitic groups, such as fleas, bugs, and mites.…”

“…In recent years, bat-associated Bartonella genotypes have been found in humans, indicating the public health importance of this parasite in bats (12–14). Bartonella and other pathogen transmission from bats to humans may occur through religious activities in caves, bat consumption or contact with contaminated products (12, 15). There are documented cases of bat-specific ectoparasites biting humans (16, 17), increasing the potential of bat-born pathogen transmission.…”

DNA-aided identification of Culex mosquitoes (Diptera: Culicidae) reveals unexpected diversity in underground cavities in Austria

“…Since tourism and modern leisure behaviour make cave visits increasingly popular, pathogens transmitted by cave-associated mosquitoes have become a topic of research, especially in tropical regions (Obame-Nkoghe et al 2017b ; Wiwanitkit 2018 ). In Austria, 33 out of 16,000 surveyed caves run as show caves (Oedl and Spötl 2016 ), but many more subterranean sites are well-frequented local attractions without regular guiding service.…”

Use of MALDI-TOF MS for the Identification of Chad Mosquitoes and the Origin of Their Blood Meal

“…51 As for Cx. rima, its presence has already been reported in some African countries, [52][53][54] but its vector role remains unknown to this day. We found that the fragment of the COI gene amplified in this study could not distinguish An.…”