The potential introduction of SARS-CoV-2, the virus responsible for the COVID-19 pandemic, into North American bat populations is of interest to wildlife managers due to recent declines of several species. Populations of little brown bats (Myotis lucifugus) have collapsed due to white-nose syndrome (WNS), a disease caused by the introduction and spread of the fungal pathogen Pseudogymnoascus destructans (Pd). Throughout much of the United States and southern Canada, large colonies of the species routinely established diurnal roosts in anthropogenic structures creating the potential for direct human contact and cross-species disease transmission. Given recent declines and the potential for further disease impacts, we collected oral swabs from eight little brown bat colonies for RT-qPCR analysis to describe the presence and prevalence of SARS-CoV-2. We visited colonies in Maryland (n = 1), New Hampshire (n = 1), New Jersey (n = 2), New York (n = 1), Rhode Island (n = 2), and Virginia (n = 1) during May-August, 2022. We have analyzed samples from 235 individuals and all have tested negative for SARS-CoV-2. Our results indicate that little brown bats are either negative for SARS-CoV-2 or that it persists in undetectable levels in populations of the Mid-Atlantic and Northeast in the summer months. Nonetheless, future work addressing other seasons or using serologic approaches may still be warranted to conclusively determine disease status.

The potential introduction of SARS-CoV-2, the virus responsible for the COVID-19 pandemic, into North American bat populations is of interest to wildlife managers due to recent declines of several species. Populations of little brown bats (Myotis lucifugus) have collapsed due to white-nose syndrome (WNS), a disease caused by the introduction and spread of the fungal pathogen Pseudogymnoascus destructans (Pd). Throughout much of the United States and southern Canada, large colonies of the species routinely established diurnal roosts in anthropogenic structures creating the potential for direct human contact and cross-species disease transmission. Given recent declines and the potential for further disease impacts, we collected oral swabs from eight little brown bat colonies for RT-qPCR analysis to describe the presence and prevalence of SARS-CoV-2. We visited colonies in Maryland (n = 1), New Hampshire (n = 1), New Jersey (n = 2), New York (n = 1), Rhode Island (n = 2), and Virginia (n = 1) during May-August, 2022. We have analyzed samples from 235 individuals and all have tested negative for SARS-CoV-2. Our results indicate that little brown bats are either negative for SARS-CoV-2 or that it persists in undetectable levels in populations of the Mid-Atlantic and Northeast in the summer months. Nonetheless, future work addressing other seasons or using serologic approaches may still be warranted to conclusively determine disease status.

Little brown bat (Myotis lucifugus) weights and SARS-CoV2 test results were collected as part of study to assess transmission potential of SARS-CoV2 in North American bat populations. It has been proposed that the SARS-CoV-2 virus originated in Asian bats and subsequently spread through human populations as a pandemic. There is concern that infected humans could transmit the virus to native North American bats, therefore the susceptibility of several North American bat species to the pandemic virus has been experimentally assessed. Big brown bats (Eptesicus fuscus) were shown to be resistant to infection by SARS-CoV-2, while Mexican free-tailed bats (Tadarida brasiliensis) became infected and orally excreted moderate amounts of virus for up to 18 days post-inoculation. Little brown bats (Myotis lucifugus) frequently contact humans, and their populations are threatened over much of their range due to white-nose syndrome, a fungal disease that is continuing to spread across North America. For this study, we experimentally challenged little brown bats with SARS-CoV-2 to determine their susceptibility, host potential, and whether the virus presents an additional risk to this species. We present data, including oral and rectal excretion, health status and serological evidence that shows this species was resistant to infection by SARS-CoV-2. These findings will provide reassurance to wildlife rehabilitators, biologists, conservation scientists, and the public at large who are concerned with possible transmission of this virus to threatened bat populations.

This is the supplementary table that accompanies the manuscript by Olival et al. entitled 'Possibility for reverse zoonotic transmission of SARS-CoV-2 to free-ranging wildlife: a case study of bats'. The table illustrates global patterns of betacoronavirus (β-CoV) associations in bats. The table lists bat species in which betacoronaviruses (β-CoVs) were detected, organized by viral subgenera and clade [for Sarbecorviruses], bat family, bat suborder, and general global region where the species of bat occurs. Reference to the published literature sources of information for each row are listed in the last column.

These data are the collection of generalized linear mixed models run for AIC comparison of the pre- and post-White-nose Syndrome bat mist-net captures and percent juveniles in capture by year, time since White-nose Syndrome at collection set, U.S Fish and Wildlife Service designated geographic units, states or NABAT grid cell, collection site mean temperature, collection site temperature range and collection site elevation. Models are inclusive of data from 1999-2019 for the little brown bat (Myotis lucifugus), northern long-eared bat (Myotis septentrionalis) and the tri-colored bat (Perimyotis subflavus).

These data are the collection of generalized linear mixed models run for AIC comparison of the pre- and post-White-nose Syndrome bat mist-net captures and percent juveniles in capture by year, time since White-nose Syndrome at collection set, U.S Fish and Wildlife Service designated geographic units, states or NABAT grid cell, collection site mean temperature, collection site temperature range and collection site elevation. Models are inclusive of data from 1999-2019 for the little brown bat (Myotis lucifugus), northern long-eared bat (Myotis septentrionalis) and the tri-colored bat (Perimyotis subflavus).

White-nose syndrome (WNS), a fungal disease that has caused catastrophic population declines of bats in eastern North America, is rapidly spreading across the continent and now threatens previously unexposed bat species in western North America. The causal agent of WNS, Pseudogymnoascus destructans, can infect many species of hibernating bats, but susceptibility to WNS varies by host species. Predicting which western bat species will be most susceptible to WNS would be of great value for establishing conservation priorities. We previously reported that certain traits of the skin microbiome of bat species in eastern North America were strongly associated with tolerance to WNS. Using these traits, we developed a model to predict WNS susceptibility of 13 species of western North American bats. Based on the model, only two bat species, Myotis velifer and Eptesicus fuscus, were predicted to be WNS-tolerant. If accurate, a greater proportion of western bat species will be susceptible to the disease compared to eastern bat species, indicating that WNS may pose a significant conservation threat in western North America.

Through the North American Bat Monitoring Program, Bat Conservation International and U.S Geological Survey (USGS) provided technical and science support to assistance in U.S. Fish and Wildlife Service Species Status Assessment (“SSA”) for the northern long-eared bat (Myotis septentrionalis), little brown bat (Myotis lucifugus), and tri-colored bat (Perimyotis subflavus). USGS facilitated the SSA data call providing data archival for repeatable and transparent analyses, provided statistical support to assess the historical, current, an future population status for each of the three species, and developed a demographic projection tool to evaluate future viability of each species under multiple threat scenarios. We assessed population trends from count surveys of wintering colonies at hibernacula for these three bat species. Winter colony counts were downloaded from the database of the North American Bat Monitoring Program (U.S. Geological Survey North American Bat Monitoring Program. Accessed 2020-12-01. NABat Request Number 12. Database Version v5.4.0).

White-nose syndrome (WNS) caused by the fungus, Pseudogymnoascus destructans (Pd) has killed millions of North American insect-eating bats. Currently, methods to prevent the disease are limited. We conducted two trials to assess potential WNS vaccine candidates in wild-caught Myotis lucifugus. In a pilot study, we immunized bats with one of four vaccine treatments or PBS as a control and challenged them with Pd upon transfer into hibernation chambers. Bats in one vaccine-treated group, that received raccoon poxviruses (RCN) expressing Pd calnexin (CAL) and serine protease (SP), developed WNS at a lower rate (1/10) than other treatments combined (14/23), although samples sizes were small. The results of a second similar trial provided additional support for this observation. Bats vaccinated orally or by injection with RCN-CAL and RCN-SP survived Pd challenge at a significantly higher rate (P = 0.01) than controls. Using RT-PCR and flow cytometry, combined with fluorescent in situ hybridization, we determined that expression of IFN-γ transcripts and the number of CD4+ T-helper cells transcribing this gene were elevated (P <0.10) in stimulated lymphocytes from surviving vaccines (n=15) compared to controls (n=3). We conclude that vaccination with virally-vectored Pd antigens induced antifungal immunity that could potentially protect bats against WNS.

White-nose syndrome (WNS) caused by the fungus, Pseudogymnoascus destructans (Pd) has killed millions of North American insect-eating bats. Currently, methods to prevent the disease are limited. We conducted two trials to assess potential WNS vaccine candidates in wild-caught Myotis lucifugus. In a pilot study, we immunized bats with one of four vaccine treatments or PBS as a control and challenged them with Pd upon transfer into hibernation chambers. Bats in one vaccine-treated group, that received raccoon poxviruses (RCN) expressing Pd calnexin (CAL) and serine protease (SP), developed WNS at a lower rate (1/10) than other treatments combined (14/23), although samples sizes were small. The results of a second similar trial provided additional support for this observation. Bats vaccinated orally or by injection with RCN-CAL and RCN-SP survived Pd challenge at a significantly higher rate (P = 0.01) than controls. Using RT-PCR and flow cytometry, combined with fluorescent in situ hybridization, we determined that expression of IFN-γ transcripts and the number of CD4+ T-helper cells transcribing this gene were elevated (P <0.10) in stimulated lymphocytes from surviving vaccines (n=15) compared to controls (n=3). We conclude that vaccination with virally-vectored Pd antigens induced antifungal immunity that could potentially protect bats against WNS.