We report an active surveillance study of the occurrence of specific antibodies to European Bat Lyssavirus Type 1 (EBLV-1) in bat species, scarcely studied hitherto, that share the same refuge. From 2004 to 2012, 406 sera were obtained from nine bat species. Blood samples were subjected to a modified fluorescent antibody virus neutralization test to determine the antibody titer. EBLV-1-neutralizing antibodies were detected in six of the nine species analyzed (Pipistrellus pipistrellus, P. kuhlii, Hypsugo savii, Plecotus austriacus, Eptesicus serotinus and Tadarida teniotis). Among all bats sampled, female seroprevalence (20.21%, 95% CI: 14.78%–26.57%) was not significantly higher than the seroprevalence in males (15.02%, 95% CI: 10.51%–20.54%). The results showed that the inter-annual variation in the number of seropositive bats in T. teniotis and P. austriacus showed a peak in 2007 (>70% of EBLV-1 prevalence). However, significant differences were observed in the temporal patterns of the seroprevalence modeling of T. teniotis and P. austriacus. The behavioral ecology of these species involved could explain the different annual fluctuations in EBLV-1 seroprevalence.

Toscana phlebovirus (TOSV) and Sicilian phlebovirus (SFSV) are endemic in the Mediterranean area where they are transmitted to humans by infected sandflies. Vertebrates of several species have been postulated to act as reservoirs of these viruses, but convincing evidence is still awaited. Among them, bats have been suggested, however documented evidence is lacking. Here we tested a total of 329 bats belonging to eight species collected from twelve localities in southern Spain for the presence of neutralizing antibodies specific to TOSV and SFSV. Positive sera were detected in Schreiber’s long-fingered bat (Miniopterus schreibersii), mouse-eared Myotis (Myotis myotis), European free-tailed bat (Tadarida teniotis), and common serotine (Eptesicus serotinus) with the latter showing the highest prevalence rates for SFSV (22.6%) and TOSV (10%). There was no difference between females and males. Results suggest that bats are not likely to play a major role in the natural cycle of these two sandfly-borne phleboviruses. However, large breeding colonies of bats can be used as sentinels for surveillance of the presence of such viruses in a given locality. In addition, capture–recapture studies should be initiated in order to understand better the dynamics of TOSV and SFSV in bat populations.

One of the principal consequences of climate warming on hibernating mammals could be the loss of optimal conditions for hibernation. Although hibernating mammals, like bats, may be particularly vulnerable to climate warming due to a potential reduction of energy saving during the hibernation, there is a lack of knowledge regarding how they will be affected and how they will respond to this impact. Here, we examine the variation in the body condition of Schreiber’s bent-winged bat (Miniopterus schreibersii) to investigate changes in the optimization energy demand. Using a 20-year dataset (1998–2017), we analyse the temporal trends of body condition in three key stages of the hibernation period: onset and end of hibernation and early activity. Our results indicate that body condition at the onset and end of hibernation have decreased significantly over these 20 years. However, despite this lower body condition, the decrease of mass loss rate in the last decade (although not significant) indicate a greater saving of fat reserves. The significant increase in winter temperatures did not affect body condition or reserve depletion, instead, lower body condition was observed with a higher number of days below 0 °C. Unlike other hibernating bat species, the females had lower fat reserves than males in all three periods considered. This study indicates that hibernation energy requirements could be changing as an adaptation to a warmer climate and that hibernating bats can survive the winter by optimizing their lower accumulation of reserves.

Astroviruses (AstVs) are enteric viruses that can cause gastroenteritis in children. This study is part of monitoring the circulation of astroviruses in children hospitalized and/or outpatients for acute gastroenteritis at the primary care center of Ouerdanine or at the Pediatric Department of the University Hospital Fattouma-Bourguiba (Monastir, Tunisia). The aims of our study were to know the prevalence of human astrovirus in clinical samples of children, characterize the strains and evaluate the infectivity of isolated strains on cell culture. Fifty stool samples were collected from children under five years old in the region of Monastir (Tunisia) from October 2010 to June 2011. All specimens were subjected to RT-PCR amplification followed by sequencing and phylogenetic analysis. The study shows a low prevalence of astrovirus (4 %) in children. The two positive samples obtained were HAstV type 3. Samples that were RT-PCR positive were cultured in CaCO-2 cells and the presence of infectious viral particles was confirmed. The phylogenetic analysis shows that the different HAstV-3 strains isolated in Tunisia are grouped into two clusters. The first cluster includes strains obtained in 2004, which belong to lineage HAstV-3a, while strains isolated in 2010 belong to lineage HAstV-3c. This study is part of monitoring the circulation of astroviruses in children younger than five years old from Monastir region, Tunisia. The results show low prevalence (4 %). All genotyped samples belonged to lineage HAstV-3c, which could be presently emerging. Two different lineages have been isolated in Tunisia: HAstV-3a in 2004 and HAstV-3c in 2010.

Background: Lyssaviruses are pathogens of bat origin of considerable zoonotic concern being the causative agent for rabies disease, however our understanding of their persistence in bat populations remains very scarce. Methods: Leveraging existing data from an extensive ecological field survey characterizing Myotis myotis and Miniopterus schreibersii bat species in the Catalonia region, we develop a data-driven spatially explicit metapopulation model to identify the mechanisms of the empirically observed persistence of European Bat Lyssavirus subtype 1 (EBLV-1), the most common lyssavirus species found in Europe. We consider different disease progressions accounting for lethal infection, immunity waning, and potential cross-species transmission when the two populations share the same refuge along the migratory path of M. schreibersii . Results: We find that EBLV-1 persistence relies on host spatial structure through the migratory nature of M. schreibersii bats, on cross-species mixing with M. myotis population, and on a disease progression leading to survival of infected animals followed by temporary immunity. The higher fragmentation along the northern portion of the migratory path is necessary to maintain EBLV-1 sustained circulation in both species, whereas persistence would not be ensured in the single colony of M. myotis. Our study provides first estimates for the EBLV-1 transmission potential in M. schreibersii bats and average duration of immunity in the host species, yielding values compatible with previous empirical observations in M. myotis bats. Conclusions: Habitats sharing and the strong spatial component of EBLV-1 transmission dynamics identified as key drivers in this ecological context may help understanding the observed spatial diffusion of the virus at a larger scale and across a diverse range of host species, through long-range migration and seeding of local populations. Our approach can be readily adapted to other zoonotic pathogens of public health concern.