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Biology subjects

Bird, B.

Publications and source records attributed to Bird, B..

4 recordsLinked to original sources

Proteomic comparison of Marburg and Kasokero virus infection in natural host Egyptian rousette bat reveals distinct antiviral pathways

Bats are natural reservoir hosts for numerous zoonotic viruses, yet the molecular mechanisms enabling viral persistence without overt disease remain incompletely understood. The Egyptian rousette bat (Rousettus aegyptiacus, ERB) is the sole known natural reservoir of Marburg virus (MARV) and a key host in the enzootic cycle of the tick-borne Kasokero virus (KASV), providing a unique system to compare host responses to different RNA viruses within the same species. Here, we applied serial cross-sectional serum proteomics integrated with tissue-specific viral kinetics to characterize systemic host responses to experimental MARV and KASV infection in captive-reared bats. Nearly 16 % of detected proteins (67/419) were found exclusively in infected animals, yet canonical acute inflammatory signatures driving pathology in other susceptible hosts were absent (e.g., in humans and non-human primates). Differential abundance and detection analyses identified both shared and virus-dependent responses, with MARV infection eliciting limited and transient perturbations, while KASV induced broader and more sustained engagement of complement, lectin pathway, and hepatometabolic proteins. Network-based analysis uncovered coordinated proteasome modules, including circulating immunoproteasome complexes, consistent with enhanced antigen-processing capacity is a feature of these virus-host dynamics. Together, these findings reveal how ERBs mount structured, virus-dependent systemic responses, offering new insight into mechanisms underlying viral infection in natural reservoir hosts.

systems biology↗

Vaccine strains of Rift Valley fever virus exhibit attenuation at the maternal-fetal placental interface

Rift Valley fever virus (RVFV) infection causes abortions in ruminant livestock and is associated with an increased likelihood of miscarriages in women. Using sheep and human placenta explant cultures, we sought to identify tissues at the maternal-fetal interface targeted by RVFV. Sheep villi and fetal membranes were highly permissive to RVFV infection resulting in markedly higher virus titers than human cultures. Sheep cultures were most permissive to wild-type RVFV and {Delta}NSm infection, while live attenuated RVFV vaccines (LAVs; MP-12, {Delta}NSs, and {Delta}NSs/{Delta}NSm) exhibited reduced replication. The human fetal membrane restricted wild-type and LAV replication, and when infection occurred, it was prominent in the maternal-facing side. Type-I and type-III interferons were induced in human villi exposed to LAVs lacking the NSs protein. This study supports the use of sheep and human placenta explants to understand vertical transmission of RVFV in mammals and whether LAVs are attenuated at the maternal-fetal interface. TeaserVaccine strains of Rift Valley fever virus have reduced infection and replication capacity in mammalian placenta

microbiology↗

Spatiotemporal patterns in Golden-cheeked Warbler breeding habitat quality and quantity

The Golden-cheeked Warbler, Setophaga chrysoparia, is a migratory songbird listed as endangered under the federal Endangered Species Act that breeds exclusively in central Texas and is heavily impacted by habitat conversion. The species relies on mixed Ashe-juniper and oak woodlands for nest-building and shelter during spring and early summer months. Using land cover data spanning the last 25 years, we conduct a geospatial analysis to quantify changes and\ identify shifts in breeding habitat quantity and quality. Since 1985, 13% of all forests within the warblers breeding range were disturbed, with greater incidences near San Antonio (32%) and Austin (24%) metropolitan areas. Additionally, data show a 45% decrease in high-quality habitat (i.e., intact mixed or evergreen core forests) and a decrease in patch size. Habitats within protected areas see a less sharp decline in habitat quality and large increases in warbler sightings, but these only represent 10% of all highest-quality habitat in the breeding range. Drastic declines in habitat quality suggest that generalized metrics of conversion may underestimate true habitat loss as degradation may impact the ecological viability of remaining forests for warbler nesting. Further evidence suggests that the few protected areas within the Texas range continue to play a significant role in warbler breeding. This information will assist researchers and managers prioritizing conservation action and will inform upcoming species status determinations.

ecology↗

Bayesian estimation of Lassa virus epidemiological parameters: implications for spillover prevention using wildlife vaccination

Lassa virus is a significant burden on human health throughout its endemic region in West Africa, with most human infections the result of spillover from the primary rodent reservoir of the virus, the natal multimammate mouse, M. natalensis. Here we develop a Bayesian methodology for estimating epidemiological parameters of Lassa virus within its rodent reservoir and for generating probabilistic predictions for the efficacy of rodent vaccination programs. Our approach uses Approximate Bayesian Computation (ABC) to integrate mechanistic mathematical models, remotely-sensed precipitation data, and Lassa virus surveillance data from rodent populations. Using simulated data, we show that our method accurately estimates key model parameters, even when surveillance data are available from only a relatively small number of points in space and time. Applying our method to previously published data from two villages in Guinea estimates the time-averaged R0 of Lassa virus to be 1.658 and 1.453 for rodent populations in the villages of Bantou and Tanganya, respectively. Using the posterior distribution for model parameters derived from these Guinean populations, we evaluate the likely efficacy of vaccination programs relying on distribution of vaccine-laced baits. Our results demonstrate that effective and durable reductions in the risk of Lassa virus spillover into the human population will require repeated distribution of large quantities of vaccine. Author SummaryLassa virus is a chronic source of illness throughout West Africa, and is considered to be a threat for widespread emergence. Because most human infections result from contact with infected rodents, interventions that reduce the number of rodents infected with Lassa virus represent promising opportunities for reducing the public health burden of this disease. Evaluating how well alternative interventions are likely to perform is complicated by our relatively poor understanding of viral epidemiology within the reservoir population. Here we develop a novel statistical approach that couples mathematical models and viral surveillance data from rodent populations to robustly estimate key epidemiological parameters. Applying our method to existing data from Guinea yields well-resolved parameter estimates and allows us to simulate a variety of rodent vaccination programs. Together, our results demonstrate that rodent vaccination alone is unlikely to be an effective tool for reducing that public health burden of Lassa fever within West Africa.

ecology↗