Location: Zoonotic and Emerging Disease Research
Project Number: 3022-32000-027-042-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Aug 1, 2026
End Date: Jul 31, 2027
Objective:
The overall objective of this project is to define zoonotic virus diversity and exposure patterns at the wildlife–farm animal–human interface in Bangladesh to strengthen early warning for pathogens that could threaten U.S. agriculture, animal health, and rural communities. Bangladesh is a high-priority One Health setting because dense human and animal populations, expanding agricultural production, wildlife contact, and repeated Nipah virus spillover create conditions that can reveal emerging threats before they spread internationally. Information generated through this work will help identify animal reservoirs, farm-interface risk pathways, and diagnostic priorities relevant to protecting U.S. livestock and agricultural workers. Specific objectives are to:
Detect and characterize known and novel zoonotic viruses in archived animal samples from Bangladesh, including oral, rectal, serum, and urine specimens collected from rodents, shrews, small fruit bats, Pteropus spp. bats, and available farm-associated animal samples.
Integrate viral sequencing results with animal, ecological, geographic, farm-interface, livestock/farm species, and available human surveillance datasets to identify host range, reservoir candidates, and potential pathways for spillover into livestock or people.
Evaluate serologic evidence of exposure to priority zoonotic viruses in available animal sera, with emphasis on pathogens of agricultural and One Health importance, including Nipah virus, Crimean-Congo hemorrhagic fever virus, and PRV.
Assess whether CCHFV or related nairoviruses are circulating silently in Bangladesh animal populations. Based on the broader geographic distribution of CCHF risk in the region, evidence of exposure may be present even though human disease has not been reported. Detecting serologic evidence of prior exposure would provide a basis for targeted future investigations in livestock, wildlife, ticks, and farm-associated environments.
Conduct focused analysis of Pteropus spp. samples from Bangladesh and neighboring countries, including Bhutan and Nepal, to better define the role of these bats in maintenance and spillover of zoonotic viruses that could affect agricultural systems directly through animal infection or indirectly through trade, workforce health, and outbreak response demands.
Approach:
During the project focus will be on laboratory analysis and data integration using animal samples already received from Bangladesh and additional Pteropus spp. samples expected from Bangladesh and neighboring countries. Sample types include oral, rectal, serum, and urine specimens from rodents, shrews, small fruit bats, Pteropus spp. bats, and available farm-associated animal samples. These materials provide an opportunity to evaluate wildlife reservoirs, peri-agricultural species, and potential livestock-interface pathways that may contribute to spillover at farm and village interfaces. We will perform capture-based viral sequencing using VirCapSeq-VERT on selected rodent, shrew, bat, and available farm-associated animal specimens to detect known and novel vertebrate viruses. Sequencing data will be processed through established bioinformatics pipelines for viral classification, genome assembly when possible, phylogenetic analysis, and comparison with existing Bangladesh wildlife, farm-animal, ecological, geographic, and human surveillance datasets. This integrated analysis will be used to identify viral diversity, host associations, reservoir candidates, and geographic patterns that may indicate risk to livestock, agricultural workers, and rural communities. High-throughput serology will be performed on available animal sera to evaluate prior exposure to priority zoonotic viruses. Assays will include targets relevant to U.S. agriculture and One Health preparedness, including Nipah virus, CCHFV, and PRV. PRV serology will be performed on bat, rodent, and available farm-associated animal samples to evaluate exposure patterns and compare animal serologic findings with prior molecular detections in bats and other available animal and human surveillance data. This will allow us to evaluate whether molecular detections reflect isolated events or broader exposure patterns across host groups and locations without relying on new testing of human cases. A specific emphasis will be placed on CCHFV. Although CCHF has not been reported in Bangladesh, the country lies near regions where competent tick vectors, livestock movement, and ecological conditions could support undetected circulation. We will screen collected animal samples for evidence of prior CCHFV exposure. If evidence is detected, future years will focus on targeted investigations in livestock, wildlife, ticks, and farm-associated environments, with collection of appropriate materials for viral genomic characterization and improved understanding of transmission pathways. For Pteropus spp., we will conduct a focused cross-country analysis using samples from Bangladesh, Bhutan, and Nepal. Molecular, serologic, ecological, and geographic data will be integrated to evaluate whether Pteropus populations contribute to maintenance, regional movement, or spillover of zoonotic viruses. Results will support risk-based surveillance strategies, identify diagnostic targets, and strengthen preparedness for pathogens that could affect U.S. livestock, agricultural productivity, and the health of farm workers.