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Kailing, M. J.

Publications and source records attributed to Kailing, M. J..

3 recordsLinked to original sources

Shifting effects of host physiological condition following pathogen establishment

Understanding host persistence with emerging pathogens is essential for conserving populations. Hosts may initially survive pathogen invasions through pre-adaptive mechanisms. However, whether pre-adaptive traits are directionally selected to increase in frequency depends on the heritability and environmental dependence of the trait and the costs of trait maintenance. Body condition is likely an important pre-adaptive mechanism aiding in host survival, although can be seasonally variable in wildlife hosts. We used data collected over seven years on bat body mass, infection, and survival to determine the role of host body condition during the invasion and establishment of the emerging disease, white-nose syndrome. We found that when the pathogen first invaded, bats with higher body mass were more likely to survive, but this effect dissipated following the initial epizootic. We also found that heavier bats lost more weight overwinter, but fat budgeting depended on infection severity. Lastly, we found little support that bat mass increased in the population after pathogen arrival, and there was high annual plasticity in individual bat masses. Overall, our results suggest that factors that contribute to host survival during pathogen invasion may diminish over time, and are potentially replaced by other host adaptations.

ecology↗

Wildlife exposure to SARS-CoV-2 across a human use gradient

Pervasive SARS-CoV-2 infections in humans have led to multiple transmission events to captive animals. While SARS-CoV-2 has a potential broad wildlife host range, most documented infections to date are found in a single species, the white-tailed deer. The extent of SARS-CoV-2 exposure among wildlife species and the factors that influence wildlife transmission risk remain unknown. We sampled 23 wildlife species for SARS-CoV-2 and examined the effects of urbanization and human use on seropositivity. Here, we document positive detections of SARS-CoV-2 RNA in six species, including the deer mouse, Virginia opossum, raccoon, groundhog, Eastern cottontail, and Eastern red bat. In addition, we found that sites with high human activity had three times higher seroprevalence than low human-use areas. We detected SARS-CoV-2 genomic sequences from nine individuals of six species which were assigned to seven Pango lineages of the Omicron variant. The close match to variants circulating in humans at the time suggests at least seven recent human-to-animal transmission events. Our data support that exposure to SARS-CoV-2 has been widespread in wildlife communities and suggests that areas with high human activity may serve as points of contact for cross-species transmission.

ecology↗

SEX-BIASED INFECTIONS SCALE TO POPULATION IMPACTS FOR AN EMERGING WILDLIFE DISEASE

Demographic factors are fundamental in shaping infectious disease dynamics. Aspects of populations that create structure, like age and sex, can affect patterns of transmission, infection intensity and population outcomes. However, studies rarely link these processes from individual to population-scale effects. Moreover, the mechanisms underlying demographic differences in disease are frequently unclear. Here, we explore sex-biased infections for a multi-host fungal disease of bats, white-nose syndrome, and link disease-associated mortality between sexes, the distortion of sex ratios, and the potential mechanisms underlying sex differences in infection. We collected data on host traits, infection intensity, and survival of five bat species at 42 sites across seven years. We found females were more infected than males for all five species. Females also had lower apparent survival over winter and accounted for a smaller proportion of populations over time. Notably, female-biased infections were evident by early hibernation and likely driven by sex-based differences in autumn mating behavior. Male bats were more active during autumn which likely reduced replication of the cool-growing fungus. Higher disease impacts in female bats may have cascading effects on bat populations beyond the hibernation season by limiting recruitment and increasing the risk of Allee effects.

ecology↗