Search Results (47)

The recent COVID-19 pandemic has renewed interest in bats, as they are natural hosts for numerous viruses, some of which have crossed species boundaries. Despite continued efforts in the past, the ecology of bat-related viruses in a significant part of national territories, such as Italy, remains largely unexplored. Herein, we describe the detection and molecular characterization of bat coronaviruses, identified during a viral survey on selected potential zoonotic pathogens (lyssavirus and coronaviruses) carried out in Sicily, southern Italy. A total number of 330 samples were collected from 149 bats in a period (November 2020–April 2023) overlapping the COVID-19 pandemic. All samples tested negative for lyssavirus and SARS-CoV-2, while 12 bats (8.05%) tested positive to a pan-coronavirus assay. Both alphacoronaviruses and betacoronaviruses were identified in samples from three species (Miniopterus schreibersii, Rhinolophus ferrumequinum, and Rhinolophus hipposideros). Strain sequences were related to coronaviruses detected in the last decade in northern Italy as well as in other countries bordering the Mediterranean basin, suggesting a widespread diffusion of these strains. This study supports the need for further monitoring efforts and early detection of circulating coronavirus genotypes, particularly for those which have been repeatedly emerging as zoonotic spillovers. Full article

Background: Emerging infectious diseases threaten human and animal health, with most pathogens originating from wildlife. Bats are natural hosts for many infectious agents. Previous studies have demonstrated that changes in some specific genes in bats may contribute to resistance to viral infections, but they have mostly overlooked the immune function of the bat gut microbiota. Aims: In this study, we used fecal transplants to transfer the gut microbiota from the Greater Horseshoe Bat (Rhinolophus ferrumequinum) into mice treated with antibiotics. The gut microbiota changes in mice were detected using 16S rRNA high-throughput sequencing technology. Flow cytometry was used to detect changes in associated immune cells in the spleen and mesenteric lymph nodes of the mice. Results: The results showed that the gut microbiota of mice showed characteristics of some bat gut microbiota. The Greater Horseshoe Bat’s gut microbiota changed some immune cells’ composition in the spleen and mesenteric lymph nodes of mice and also conferred a faster and higher proportion of natural killer cell activation. Conclusion: This result provides new evidence for the regulatory immune function of bat gut microbiota and contributes to a deeper insight into the unique immune system of bats. Full article

SADS-CoV, a recently identified Rhinolophus bat coronavirus HKU2-associated swine coronavirus, is a malignant pathogen that causes acute diarrhea, severe diarrhea, and weight loss in infected piglets. The virus was first detected in Guangdong Province, China, in 2017 and has since been observed in Jiangxi, Fujian, and Guangxi Provinces. In 2023, the virus was detected in Henan Province, in inland China. This virus can infect various cell lines, including human cell lines, showing significant potential for cross-species transmission and posing a possible zoonotic threat. However, the molecular biology of SADS-CoV remains largely unknown, and there are no commercially available therapeutics or vaccines to prevent SADS-CoV infection. In this review, an update on progress in SADS-CoV research is provided, with a focus on the history of outbreaks, the characteristics of the virus, its interactions with the host, and developments in therapeutics and vaccines. Full article

Prince Mohammed bin Salman Royal Reserve (PMBSRR or the Reserve) is located in the northwest of Saudi Arabia and covers an area of 24,500 km² of both marine and terrestrial ecosystems. Bat surveys have been undertaken between 2022 and 2024 across PMBSRR as part of the Reserve’s groundbreaking conservation efforts and this is the first published checklist of the bat species present within the Reserve. Survey methods included bat capture, roost inspection, and acoustic recordings. Tissue and faecal samples were taken during the surveys and compared to a global database to confirm the species present. The survey results confirmed the presence of 18 species belonging to 14 genera of eight families. This research has greatly expanded our knowledge on the diversity of bats within the Kingdom, increasing the reported bat species in the Tabuk region by seven species, with the addition of Rhyneptesicus nasutus, Rhinolophus hipposideros, Nycteris thebaica, Tadarida aegyptiaca, Rhinopoma microphyllum, Taphozous nudiventris, and Taphozous perforatus and increasing the number of species within Saudi Arabia by one species, with the addition of Vansonia rueppellii. Full article

Mammals may experience physical changes from birth, and their diet varies at different stages of life. This study investigates the impact of development on the diet composition of three horseshoe bats: Rhinolophus euryale, R. hipposideros, and R. ferrumequinum in the Basque Country, north of the Iberian Peninsula. The diets of juvenile and adult individuals of each species were obtained by analysing their droppings using metabarcoding and then compared at (1) the taxonomic and (2) prey trait levels (size, flying speed, hardness). The diets of juvenile and adult individuals of R. euryale and R. hipposideros showed significant differences at the taxonomic level and regarding prey traits. In contrast, in the case of R. ferrumequinum, we could only observe discernible diet patterns through the trait analysis. Additionally, we discovered a shared pattern: younger individuals tend to feed on easier-to-hunt and/or handle smaller and smoother prey. The varying degrees of dissimilarity between juvenile and adult diets observed in this study suggest that the relative importance of psychomotor development, foraging strategies, prey discrimination, and/or spatial learning may differ among species. These findings contribute to conservation efforts, especially by recognising the dietary needs of juveniles for their survival and successful development. Full article

The present study contributes to the morphogenesis of the Miresii Cave, located in Cheia Mare of Dâmbovița in the area of the Bran—Dragoslavele Corridor, an important tourist axis in Romania. The main aim of the research is the proposal to the Scientific Council of Piatra Craiului National Park to bring to the attention of the national decision-making commissions that the cave be declared a natural monument. The inventory of this speleological geomorphosite suggested its inclusion in a thematic geotouristic circuit integrated into national and EU-protected natural areas. The novelty of the present research lies in the fact that the cave has never been studied before, being difficult to access. This cave, spatially found in the strict protection zone of the national park, is not included in its management plan. When being integrated into other nature protection areas, it is necessary to exclude any form of recreational tourism so that the cave can be exploited as a geotouristic resource strictly for research and educational purposes. The morphogenetic analysis of the cave, based on the information synthesized from geomorphological and geological literature, allowed us to decipher the morphological individualization of Miresii Cave in the local and regional geocronomorphological context, in accordance with the chronological separation of the karstification phenomenon manifested first in phreatic and later in vadose karst. The diversified typology of speleothems has been rendered according to the geomorphologic generating processes. The identification of the Rhinolophus ferrumequinum chiropteran colony and observations of its biotope highlighted the ecological significance of the cave. The inventory of the individuals of the colony led to the conclusion that the cave harbors one of the first two largest bat communities of this species in the national park and the adjacent depressional corridor. The present study may allow the documentation of the photographs and description of the geomorphosite integrated into the proposed thematic circuit to be included on billboards and in promotional brochures. Thus, it could also be useful for the decision-making authorities of Rucar and Podu Dâmboviței villages, which are interested in making decisions related to the promotion of geotourism, especially due to the existence of numerous geological and geomorphological tourist resources in the administrative territories. Full article

RaTG13 is phylogenomically the closest related coronavirus to SARS-CoV-2; consequently, understanding the provenance of this high-value genome sequence is important in understanding the origin of SARS-CoV-2. While RaTG13 was described as being generated from a Rhinolophus affinis fecal swab obtained from a mine in Mojiang, Yunnan, numerous investigators have pointed out that this is inconsistent with the low proportion of bacterial reads in the sequencing dataset. Metagenomic analysis confirms that only 10.3% of small-subunit (SSU) rRNA sequences in the dataset are bacterial, which is inconsistent with a fecal sample. In addition, the bacterial taxa present in the sample are shown to be inconsistent with fecal material. The assembly of mitochondrial SSU rRNA sequences in the dataset produces a sequence 98.7% identical to R. affinis mitochondrial SSU rRNA, indicating that the sample was generated from R. affinis or a closely related species. In addition, 87.5% of the reads in the dataset map to the Rhinolophus ferrumequinum genome, and 62.2% of these map to protein-coding genes, indicating that the dataset represents a Rhinolophus sp. transcriptome rather than a fecal swab sample. Differential gene expression analysis reveals that the pattern of expressed genes in the RaTG13 dataset is similar to that of RaTG15, which was also collected from the Mojiang mine. GO enrichment analysis reveals the overexpression of spermatogenesis- and olfaction-related genes in both datasets. This observation is consistent with a mating plug found in female Rhinolophid bats and suggests that RaTG13 was mis-sampled from such a plug. A validated natural provenance of the RaTG13 dataset throws into relief the unusual features of the SARS-CoV-2 genome. Full article

Coronaviruses (CoVs), the largest positive-sense RNA viruses, have caused infections in both humans and animals. The cross-species transmission of CoVs poses a serious threat to public health. Rodents and bats, the two largest orders of mammals, serve as significant natural reservoirs for CoVs. It is important to monitor the CoVs carried by bats and rodents. In this study, we collected 410 fecal samples from bats and 74 intestinal samples from rats in Yunnan Province, China. Using RT-PCR, we identified one positive sample for alphacoronavirus (TC-14) from Rhinolophus sinicus (Chinese rufous horseshoe bat) and two positive samples for betacoronavirus (GS-53, GS-56) from Apodemus ilex (Rodentia: Muridae). We successfully characterized the complete genomes of TC-14 and GS-56. Phylogenetic analysis revealed that TC-14 clustered with bat CoV HKU2 and SADS-CoV, while GS-56 was closely related to rat CoV HKU24. The identification of positive selection sites and estimation of divergence dates further helped characterize the genetic evolution of TC-14 and GS-56. In summary, this research reveals the genetic evolution characteristics of TC-14 and GS-56, providing valuable references for the study of CoVs carried by bats and rodents in Yunnan Province. Full article

Swine acute diarrhoea syndrome coronavirus (SADS-CoV; Coronaviridae, Rhinacovirus) was detected in 2017 in Guangdong Province (China), where it caused high mortality rates in piglets. According to previous studies, SADS-CoV evolved from horseshoe bat reservoirs. Here, we report the first five Rhinacovirus genomes sequenced in horseshoe bats from Vietnam and their comparisons with data published in China. Our phylogenetic analyses provided evidence for four groups: rhinacoviruses from Rhinolphus pusillus bats, including one from Vietnam; bat rhinacoviruses from Hainan; bat rhinacoviruses from Yunnan showing a divergent synonymous nucleotide composition; and SADS-CoV and related bat viruses, including four rhinacoviruses from Vietnam sampled in Rhinolophus affinis and Rhinolophus thomasi. Our phylogeographic analyses showed that bat rhinacoviruses from Dien Bien (Vietnam) share more affinities with those from Yunnan (China) and that the ancestor of SADS-CoVs arose in Rhinolophus affinis circulating in Guangdong. We detected sequencing errors and artificial chimeric genomes in published data. The two SADS-CoV genomes previously identified as recombinant could also be problematic. The reliable data currently available, therefore, suggests that all SADS-CoV strains originate from a single bat source and that the virus has been spreading in pig farms in several provinces of China for at least seven years since the first outbreak in August 2016. Full article

Sexual dimorphism of calls is common in animals, whereas studies on the molecular basis underlying this phenotypic variation are still scarce. In this study, we used comparative transcriptomics of cochlea to investigate the sex-related difference in gene expression and alternative splicing in four Rhinolophus taxa. Based on 31 cochlear transcriptomes, we performed differential gene expression (DGE) and alternative splicing (AS) analyses between the sexes in each taxon. Consistent with the degree of difference in the echolocation pulse frequency between the sexes across the four taxa, we identified the largest number of differentially expressed genes (DEGs) and alternatively spliced genes (ASGs) in R. sinicus. However, we also detected multiple DEGs and ASGs in taxa without sexual differences in echolocation pulse frequency, suggesting that these genes might be related to other parameters of echolocation pulse rather than the frequency component. Some DEGs and ASGs are related to hearing loss or deafness genes in human or mice and they can be considered to be candidates associated with the sexual differences of echolocation pulse in bats. We also detected more than the expected overlap of DEGs and ASGs in two taxa. Overall, our current study supports the important roles of both DGE and AS in generating or maintaining sexual differences in animals. Full article

Bats are reservoirs for various pathogens, including SARS-like coronaviruses (CoVs). Understanding the distribution of bat species is crucial to identifying areas where viral spillover from bats to other animals or humans might occur. In this study, we performed species distribution modeling to predict suitable habitats within Thailand under current and predicted future climate conditions for Rhinolophus acuminatus, a bat species that has been found to host SARS-CoV-2-related viruses. Our assessment of current conditions revealed that temperature seasonality had the greatest impact on habitat suitability and that suitable habitats were primarily restricted to the southern and eastern regions of Thailand. Over time, the projections indicate a diminishing availability of suitable habitats, suggesting a potential trend toward migration into neighboring areas. We next combined modeled bat distribution with urbanization data to estimate regions in Thailand where bat–human interactions might occur. The resulting map highlighted regions of heightened interaction risk, encompassing approximately 46,053.94 km² across 58 provinces and representing approximately 9.24% of Thailand’s total area. These risk concentrations are prominently situated in the southern, central, and eastern Thai regions, with extensions into neighboring border areas. Our findings will significantly aid future risk surveillance efforts and enhance the effectiveness of monitoring and managing emerging diseases within the country and in contiguous regions. Full article

Bats are a major reservoir of zoonotic viruses, including coronaviruses. Since the emergence of SARS-CoV in 2002/2003 in Asia, important efforts have been made to describe the diversity of Coronaviridae circulating in bats worldwide, leading to the discovery of the precursors of epidemic and pandemic sarbecoviruses in horseshoe bats. We investigated the viral communities infecting horseshoe bats living in Northern Vietnam, and report here the first identification of sarbecoviruses in Rhinolophus thomasi and Rhinolophus siamensis bats. Phylogenetic characterization of seven strains of Vietnamese sarbecoviruses identified at least three clusters of viruses. Recombination and cross-species transmission between bats seemed to constitute major drivers of virus evolution. Vietnamese sarbecoviruses were mainly enteric, therefore constituting a risk of spillover for guano collectors or people visiting caves. To evaluate the zoonotic potential of these viruses, we analyzed in silico and in vitro the ability of their RBDs to bind to mammalian ACE2s and concluded that these viruses are likely restricted to their bat hosts. The workflow applied here to characterize the spillover potential of novel sarbecoviruses is of major interest for each time a new virus is discovered, in order to concentrate surveillance efforts on high-risk interfaces. Full article

Moths are among the most diverse and abundant animals. They have evolved a suite of acoustic defenses, such as producing ultrasound to guard against predation by low-duty-cycle bats. Recently, we found that the ultrasonic clicks of several moth species can also help decrease the capture success of high-duty-cycle bats. We tested whether moth clicks could advertise moth toxicity and/or jam the echolocation calls of high-duty-cycle bats. We examined the acoustic response of a hawkmoth (Cechenena minor) and a tiger moth (Creatonotos transiens) to free-flying horseshoe bats, Rhinolophus osgoodi. C. minor and C. transiens produced anti-bat ultrasonic clicks with an average duty cycle of 22.3% and 4.9%, respectively. The clicks of C. minor overlapped spectrally with the echolocation calls of R. osgoodi. C. minor occasionally emitted clicks immediately after the end of bat feeding buzzes. The clicks of C. transiens did not overlap spectrally with the echolocation calls of R. osgoodi. More than half the click sequences of C. transiens were produced before the emergence of bat feeding buzzes and did not overlap temporally with the feeding buzzes. Moreover, we found that C. minor was palatable and C. transiens was unpalatable to R. osgoodi. These results suggest that C. minor might be capable of jamming R. osgoodi and might also use ultrasonic clicks as warning signals. The clicks of C. transiens probably function to advertise moth toxicity. This study highlights the diversity of moth anti-bat sounds and illustrates the potential mechanisms of moth acoustic defense against high-duty-cycle bats. Full article

Bats are well-known to be natural reservoirs of various zoonotic coronaviruses, which have caused outbreaks of severe acute respiratory syndrome (SARS) and the COVID-19 pandemic in 2002 and 2019, respectively. In late 2020, two new Sarbecoviruses were found in Russia, isolated in Rhinolophus bats, i.e., Khosta-1 in R. ferrumequinum and Khosta-2 in R. hipposideros. The potential danger associated with these new species of Sarbecovirus is that Khosta-2 has been found to interact with the same entry receptor as SARS-CoV-2. Our multidisciplinary approach in this study demonstrates that Khosta-1 and -2 currently appear to be not dangerous with low risk of spillover, as confirmed by prevalence data and by phylogenomic reconstruction. In addition, the interaction between Khosta-1 and -2 with ACE2 appears weak, and furin cleavage sites are absent. While the possibility of a spillover event cannot be entirely excluded, it is currently highly unlikely. This research further emphasizes the importance of assessing the zoonotic potential of widely distributed batborne CoV in order to monitor changes in genomic composition of viruses and prevent spillover events (if any). Full article

The spread of antimicrobial resistance is one of the major health emergencies of recent decades. Antimicrobial-resistant bacteria threaten not only humans but also populations of domestic and wild animals. The purpose of this study was to evaluate the distribution of antibiotic resistance (AMR) and multidrug resistance (MDR) in bacterial strains isolated from six Southern-Italian bat populations. Using the disk diffusion method, we evaluated the antimicrobial susceptibility of 413 strains of Gram-negative bacteria and 183 strains of Gram-positive bacteria isolated from rectal (R), oral (O) and conjunctival (C) swabs of 189 bats belonging to 4 insectivorous species (Myotis capaccinii, Myotis myotis, Miniopterus schreibersii and Rhinolophus hipposideros). In all bat species and locations, numerous bacterial strains showed high AMR levels for some of the molecules tested. In both Gram-negative and Gram-positive strains, the resistance patterns ranged from one to thirteen. MDR patterns varied significantly across sites, with Grotta dei Pipistrelli in Pantalica displaying the highest levels of MDR (77.2% of isolates). No significant differences were found across different bat species. Monitoring antibiotic resistance in wildlife is a useful method of evaluating the impact of anthropic pressure and environmental pollution. Our analysis reveals that anthropic contamination may have contributed to the spread of the antibiotic resistance phenomenon among the subjects we examined. Full article