Detection of bacterial and protozoan pathogens in individual bats and their ectoparasites using high-throughput microfluidic real-time PCR

A wingless fly on a winged mammal: host-parasite dynamics between Basilia travassosi (Diptera: Nycteribiidae) and Myotis lavali (Chiroptera: Vespertilionidae)

Nycteribiidae encompasses a specialized group of wingless blood-sucking flies that parasitize bats worldwide. Such relationships are frequently species- or genus-specific, indicating unique eco-evolutionary processes. However, despite this significance, comprehensive studies on the relationships of these flies with their hosts, particularly in the New World, have been scarce. Here, we provide a detailed description of the parasitological patterns of nycteribiid flies infesting a population of Myotis lavali bats in the Atlantic Forest of northeastern Brazil, considering the potential influence of biotic and abiotic factors on the establishment of nycteribiids on bat hosts. From July 2014 to June 2015, we captured 165 M. lavali bats and collected 390 Basilia travassosi flies. Notably, B. travassosi displayed a high prevalence and was the exclusive fly species parasitizing M. lavali in the surveyed area. Moreover, there was a significant predominance of female flies, indicating a female-biased pattern. The distribution pattern of the flies was aggregated; most hosts exhibited minimal or no parasitism, while a minority displayed heavy infestation. Sexually active male bats exhibited greater susceptibility to parasitism compared to their inactive counterparts, possibly due to behavioral changes during the peak reproductive period. We observed a greater prevalence and abundance of flies during the rainy season, coinciding with the peak reproductive phase of the host species. No obvious correlation was observed between the parasite load and bat body mass. Our findings shed light on the intricate dynamics of nycteribiid-bat interactions and emphasize the importance of considering various factors when exploring bat-parasite associations.

Molecular survey of hemoplasmas and Coxiella burnetii in vampire bats from northern Brazil

In addition to zoonotic viral pathogens, bats can also harbor bacterial pathogens, including hemoplasmas (hemotropic mycoplasmas) and Coxiella burnetii. The present study aimed to investigate, using molecular techniques, the presence of hemoplasmas and C. burnetii in spleen samples from vampire bats in northern Brazil. For this purpose, between 2017 and 2019, spleen samples were collected from Desmodus rotundus (n = 228) and Diaemus youngii (n = 1) captured in the states of Pará (n = 207), Amazonas (n = 1), Roraima (n = 18) and Amapá (n = 3). DNA samples extracted from the bat spleen and positive in PCR for the endogenous gapdh gene were subjected to conventional PCR assays for the 16S rRNA, 23S rRNA and RNAse P genes from hemoplasmas and to qPCR based on the IS1111 gene element for C. burnetii. All spleen samples from vampire bats were negative in the qPCR for C. burnetii. Hemoplasmas were detected in 10 % (23/229) of spleen samples using a PCR based on the 16S rRNA gene. Of these, 21.73 % (5/23) were positive for the 23S rRNA gene and none for the RNAseP gene. The seven hemoplasma 16S rRNA sequences obtained were closely related to sequences previously identified in vampire bats from Belize, Peru and Brazil. The 23S rRNA sequence obtained revealed genetic proximity to hemoplasmas from non-hematophagous bats from Brazil and Belize. The analysis revealed different circulating genotypes among Brazilian vampire bats, in addition to a trend towards genera-specific hemoplasma genotypes. The present study contributes to the knowledge of the wide diversity of hemoplasmas in vampire bats.