Diversity and Epidemiology of Bat Trypanosomes: A One Health Perspective

Abstract

Bats (order Chiroptera) have been increasingly recognised as important reservoir hosts for human and animal pathogens worldwide. In this context, molecular and microscopy-based investigations to date have revealed remarkably high diversity of Trypanosoma spp. harboured by bats, including species of recognised medical and veterinary importance such as Trypanosoma cruzi and Trypanosoma evansi (aetiological agents of Chagas disease and Surra, respectively). This review synthesises current knowledge on the diversity, taxonomy, evolution and epidemiology of bat trypanosomes based on both molecular studies and morphological records. In addition, we use a One Health approach to discuss the significance of bats as reservoirs (and putative vectors) of T. cruzi, with a focus on the complex associations between intra-specific genetic diversity and eco-epidemiology of T. cruzi in sylvatic and domestic ecosystems. This article also highlights current knowledge gaps on the biological implications of trypanosome co-infections in a single host, as well as the prevalence, vectors, life-cycle, host-range and clinical impact of most bat trypanosomes recorded to date. Continuous research efforts involving molecular surveillance of bat trypanosomes are required for improved disease prevention and control, mitigation of biosecurity risks and potential spill-over events, ultimately ensuring the health of humans, domestic animals and wildlife globally.

Trypanosomatid Richness Among Rats, Opossums, and Dogs in the Caatinga Biome, Northeast Brazil, a Former Endemic Area of Chagas Disease

“…Here, we observed a trypanosomatid sequence that phylogenetically grouped together with sequences from the T. cruzi clade as well as a previously undescribed host-parasite interaction, namely, R. rattus infected by C. mellificae . In addition, according to Austen and Barbosa (2021) , mixed infection detection in a host and the understanding of multihost parasite dynamics are priorities from now on, and detection of this type of infection is only possible through NGS.…”

Molecular detection of Trypanosoma (Trypanosomatidae) in bats from Thailand, with their phylogenetic relationships

“…The increase in research in recent decades has highlighted the importance of bats as a natural reservoir for several zoonotic pathogens, including Trypanosoma . Bats play an important epidemiological role in the transmission of zoonotic diseases in the context of One Health (Calisher et al ., 2006; Letko et al ., 2020; Austen and Barbosa, 2021). This discovery has sparked the interest and concern of experts.…”

“…According to BI and ML analyses, the remaining sequences were assigned to multiple bat trypanosome lineages. The current findings revealed a monophyletic clade consisting of members of the subgenus Schizotrypanum , which agrees with previous studies (Cavazzana et al ., 2010; Clément et al ., 2020; Austen and Barbosa, 2021). Trypanosoma cruzi is the only pathogenic Schizotrypanum species, while other species are restricted to bats such as T. dionisii have been shown to not infect BALB/c mice (Lima et al ., 2012).…”

“…(2016) detected the presence of T. dionisii DNA in the cardiac tissue of a patient in Espírito Santo state, Brazil. This discovery increased concerns about pathogenicity of T. dionisii and potential transmission to humans and other animals (Austen and Barbosa, 2021). Sequences from the current study clustered together with T. dionisii from Japan (Mafie et al ., 2018), China (Cai et al ., 2019; Wang et al ., 2019), Brazil (Cavazzana et al ., 2010), UK (Hamilton et al ., 2012 a ) and Switzerland and Taiwan (Clément et al ., 2020), but were separated from two isolates from Europe (Stevens et al ., 1999).…”

“…(2020). Other studies, however, have consistently identified T. noyesi as a sister clade to T. wauwau (Espinosa-lvarez et al ., 2018; Austen and Barbosa, 2021). The different placement of T. noyesi could be attributed to the different target genes used in each study.…”