Jasim Uddin

Bovine viral diarrhea virus (BVDV) is globally endemic, with the ability to establish persistent infection (PI) being central to its complex epidemiology. Currently the genetic variability of BVDV in Bangladesh remains poorly understood. This study involved a survey in commercial dairy herds in the south-eastern part of Bangladesh in 2024/2025. A total of 373 blood samples were collected from cattle in 24 dairy herds. Serum and buffy coat samples were analyzed using antibody-ELISA and RT-qPCR targeting the 5′-UTR region, followed by sequencing. The MDBK cell line was used for virus isolation and biotyping. Herd and animal-level seroprevalences were 83.3% and 15.3%, respectively, while the corresponding viremic rates were 79.2% and 11.0%. Analysis of 41 sequences identified nine distinct BVDV-1 subgenotypes (1a, 1b, 1c, 1d, 1e, 1 k, 1p, 1o, and 1v), with BVDV-1b (41.5%) and BVDV-2a (14.6%) predominating. Additionally, five HoBiPeV-a pestiviruses were detected. Among antigen-positive cattle, 38 (92.68%) were identified as transiently infected and 3 (7.3%) were confirmed as PI. Six (14.6%) and 27 (65.9%) were identified as cytopathic and non-cytopathic biotypes, respectively. Risk factors for BVDV seropositivity included: female sex (OR: 3.0), clinical disease in the past three months (OR: 2.4), crowding (OR: 2.9), and lack of dedicated clothing for farm workers (OR: 5.7). Active infection was associated with calves (OR: 6.2), heifers (OR: 2.3), stunted growth (OR: 3.0), technician-performed artificial insemination (OR: 10.4), and frequent neighboring farm visits (OR: 3.1). This study has provided data crucial for formulating prevention and control strategies against BVDV to safeguard the Bangladeshi dairy industry.

Classical swine fever (CSF) is an important viral disease of pigs caused by classical swine fever virus (CSFV), with major impacts on animal health and the livestock industry. This study aimed to estimate the seroprevalence of CSFV antibodies in pigs in Bali, assess potential risk factors associated with seropositivity, and describe pathological changes in clinically suspected cases confirmed by rRT-PCR. From September to December 2023, 470 blood samples from pigs with no available vaccination records were collected across Bali and tested using C-ELISA. In addition, 15 pigs showing CSF signs were necropsied for pathological and rRT-PCR evaluation. Six were confirmed CSFV-positive. The overall seroprevalence was 40.8% (192/470, 95% CI: 36.4–45.4). The highest prevalence occurred in Klungkung regency (65.4%, 17/26). Pigs from urban areas were 1.76 times more likely to be seropositive (OR: 1.76, 95% CI: 1.18–2.64) than those from rural areas. By age, pigs under two years were 1.21 times more likely to be seropositive (OR: 1.21, 95% CI: 0.65–2.23), while crossbred pigs were 1.27 times more likely (OR: 1.27, 95% CI: 0.85–1.88) compared to purebreds; however, these differences were not statistically significant. Only location (urban vs. rural) showed a significant association. Pathological changes were observed in the skin, brain, trachea, lungs, kidney, spleen, and intestines. This study demonstrates a relatively high seroprevalence of CSFV in Bali. The limited vaccination records suggests minimal vaccine coverage, indicating that the high seroprevalence most likely reflects natural infection.

Bovine viral diarrhea virus (BVDV) remains a signiicant and highly contagious pathogen that markedly impacts production and reproductive performances of diierent animals worldwide. .is review represents the global epidemiology of BVDV, emphasizing its genetic diversity, prevalence, host range, associated risk factors, diagnostic advancements, and control strategies. A systematic electronic search was performed to retrieve relevant published articles. A total of 248 studies published over the past 26 years (from January 2000 to March 2025) across 69 countries were included. Data showed that BVDV-1 has been detected across all the continents and comprises 25 subgenotypes (1a-1x and Chinese ZM-95), of which the predominant subgenotypes are 1a, 1b, and 1c. Multiple subgenotypes, such as BVDV-1f, 1g, 1h, 1k, 1l, 1r, 1s, 1t, 1u, and 1x, were distinct and circulating in European countries. Additionally, ,ve subgenotypes (2a–2e) of BVDV-2 have been identiied, with BVDV-2a being the most frequently reported in diierent geographical locations. Notably, the emergence of HoBi-like pestivirus subgenotypes (BVDV-3a–3d) has been detected in Russia, Italy, ,ailand, India, and Bangladesh. Overall, the high prevalence of BVDV has been reported in various European (2.9%–87.1%) and Asian countries (0.2%–89.49%). Although cattle are the primary host, BVDV infections have been documented across a wide range of domestic and wild species, including buualo, sheep, goats, deer, bison, yak, camelids (camels, alpacas, and llamas), pigs, and wild boar. While Ag/Ab-ELISA remains a widely used diagnostic method, advanced techniques, such as RT-qPCR, CRISPR-Cas12a, RT-LAMP, and genome sequencing, are utilized for connrmatory identiication and genotyping of BVDV. Introduction of persistently infected (PI) animals into herds, grazing on common pasture, animal movements, mixed farming practices, and unhygienic breeding practices were frequently documented as potential risk factors. Key measures for controlling and eradicating BVDV include culling of PI animals, prophylactic vaccination, and avoiding mixed farming practices.

The bovine viral diarrhea virus (BVDV) infects a wide range of domestic and wild mammals. This review hypothesized that there might be cross-species transmission of BVDV. Therefore, the aim was to explore the BVDV-5′ UTR and N-pro sequence-based evidence to understand host plasticity among different animals. A total of 146 unique BVDV sequences retrieved from GenBank, originating from 12 distinct mammalian species that are submitted from 55 countries, were analyzed. The phylogenetic analysis revealed that all three BVDV species exhibited genetic relatedness infecting diverse animal species. BVDV-1 sequences obtained from cattle, buffalo, and pigs and BVDV-2 and HoBi-like pestivirus sequences from cattle, goats, and sheep showed a genetic resemblance. Surprisingly, cattle and buffalo in China, cattle and yak in Mongolia, cattle and wild boar in Serbia, cattle and deer in Mexico, cattle and alpacas in Canada, goats and pigs in the USA, and sheep and buffalo in Argentina were infected with BVDV-1 within the same county and strongly positioned in the same cluster, indicating potential spillover with host tropism. Moreover, BVDV sequences isolated from various neighboring countries clustered closely, suggesting potential cross-border transmission events. Based on genomic evidence, the BVDV transmission cycle could be depicted, where cattle act as a primary source of infection, while other domestic and wild animals maintain the infection ecology within their habitat due to virus tropism.

In sheep, the innate immune response of mammary epithelial cells (MECs) plays a central role in combating mastitis, yet our understanding of their resistance mechanisms remains limited. This study aimed to elucidate the gene expression profiles of ovine MECs following in vitro stimulation with Staphylococcus aureus (S. aureus) using RNA-Seq technology. Bioinformatics analysis identified a total of 175 differentially expressed genes (DEGs), including 172 up-regulated and 3 down-regulated genes in the stimulated group compared to the non-stimulated control group. Gene ontology annotation and functional pathway analysis indicated that these DEGs are primarily involved in ribosomal functions, which are essential for protein synthesis and first target of pathogens, as well as in immune response dysregulations, infection, phagocytosis, and bacterial invasion of epithelial cells. Validation via quantitative real-time PCR (qRT-PCR) confirmed the RNA-Seq results. Our results revealed that DEGs converged on innate immune pathways (TLR, NOD-like receptor, NF-κB, MAPK), cytoskeletal remodeling and translational control, indicating inflammatory activation and cell injury in oMECs and highlighting candidate targets for mastitis resistance selection against S. aureus. These findings significantly contribute to the understanding of how ovine MECs respond to S. aureus stimulation, providing a foundation for further research, particularly regarding the immune defense mechanisms, strategies and implications in dairy industry.

Over the decades, cattle have not been considered primary hosts for influenza A viruses (IAV), and their role in influenza epidemiology has been largely unrecognized. While bovines are known reservoirs for influenza D virus, the recent emergence of highly pathogenic avian influenza (HPAI) H5N1 clade 2.3.4.4b in U.S. dairy cattle marks an alarming shift in influenza ecology. Since March 2024, this virus has affected thousands of dairy cows, causing clinical signs such as fever, reduced feed intake, drastic declines in milk production, and abnormal milk appearance. Evidence suggests that the virus may be replicated within mammary tissue, raising urgent concerns about milk safety, foodborne transmission, and occupational exposure. This review highlights the unprecedented expansion of viruses into bovine populations, exploring the potential for host adaptation, and interconnected roles of pets, peridomestic animals, and human exposure within shared environments. The potential impacts on dairy production, food safety, and zoonotic spillover highlight the urgent need for integrated One Health surveillance to stay ahead of this evolving threat.

Lumpy skin disease virus (LSDV), a transboundary pathogen threatening cattle health in South and Southeast Asia, presents growing challenges for disease control. This study combined serological, molecular, and genomic approaches to investigate LSDV in Barura Upazila, Bangladesh. Serological screening of 424 cattle using a commercial ELISA revealed a high seroprevalence of 55.5% (95% CI: 50.7–60.3), indicating widespread exposure. Although differences were observed by age and breed, no significant associations were found with seropositivity, suggesting broad regional circulation. Real-time PCR confirmed LSDV DNA in all 20 clinically infected animals, with consistent P32 gene amplification. Two samples with low Cq values underwent whole-genome sequencing. The complete genomes of LSDV-L2/2024 and LSDV-L3/2024 showed >99.6% identity with the reference strain LSDV-29, yet carried unique genomic features, including truncated or variant ORFs and immune-related gene differences. Phylogenetic analysis of the DNA polymerase gene revealed distinct clustering: L2/2024 aligned with South Asian isolates, while L3/2024 grouped with strains from Africa, the Middle East, and Europe. These results highlight co-circulation of genetically diverse strains and possible cross-regional introductions. Overall, our findings underscore the evolutionary plasticity of LSDV and the critical need for ongoing genomic surveillance to guide targeted vaccine development and disease control strategies.

This study aimed to analyze the demographic, temporal, and spatial characteristics of animal bite (AB) cases in humans across 12 Upazilas within Mymensingh district of Bangladesh.
Retrospective hospital-based data from individual AB cases for 2022 and 2023 were collected from S.K Hospital. The dataset included information on victim demographics, bite details, vaccination information, and Rabies Immune Globulin (RIG) administration. Additionally, monthly case counts from 2016 to 2024 were sourced and analyzed to identify trends. Descriptive statistics and time series analysis using the seasonal decomposition technique were conducted. Risk maps for animal bites in 2022 and 2023 were generated using a standardized incidence ratio (SIR) approach.
An almost two-fold increase in the proportion of category 3 bites receiving RIG from 3.6% in 2022 to 6.5% in 2023 was noted. Only 9.7% (2022) and 16.9% (2023) of bite victims received PEP on the day of exposure, whereas 76.5% (2022) and 84.6% (2023) received PEP within 24 hours. Moreover, significant seasonal patterns and annual increasing trends in AB cases were observed. Males and children under 14 years old had a higher risk of being bitten. Dogs (48.2% in 2022) and cats (52.6% in 2023) were identified as the primary animals responsible for the bites. Notably, the legs were the body part most frequently bitten. The bites risk map identified four high risk Upazilas.
Despite improvements in PEP coverage achieved within 24 hours, a critical gap remains in same-day PEP coverage in both years. The study results also suggest other potential improvements in healthcare practices or treatment protocols, and the need for a veterinary surveillance system. Increasing AB cases highlight the need to enhance surveillance and control measures. Targeted awareness campaigns tailored to high-risk groups such as males and children under 14 years of age, along with preventive programs focused on dogs are imperative. Coordinated One Health efforts among healthcare professionals, veterinarians, policymakers, and community stakeholders are crucial to effectively mitigate the incidence of AB cases, safeguarding public health and eliminate dog mediated rabies by 2030 in the region.

Birds are known to harbour a wide range of pathogenic viruses, including the beak and feather disease virus (BFDV; species, Circovirus parrot), which poses a significant threat to the conservation of endangered avian species. This study reports the genomic identification and characterisation of a novel psittaciform chaphamaparvovirus (PsChPV-6) and BFDV, sequenced from the faecal samples of healthy Alexandrine parakeets (Psittacula eupatria). PsChPV-6 is a linear, single-stranded DNA virus consisting of 4232 nucleotides (nt) with a high A + T content and five predicted open reading frames (ORFs). Key proteins encoded by PsChPV-6, such as the nonstructural protein 1 (NS1) and major capsid protein VP1, demonstrate strong sequence similarities to other avian parvoviruses, with conserved motifs in NS1 crucial for viral replication. The presence of a previously uncharacterised ORF1 region suggests strain-specific viral features that warrant further exploration. BFDV is a circular single-stranded DNA virus in the Circoviridae family and was also identified in the samples. Phylogenetic analysis positioned PsChPV-6 within the Chaphamaparvovirus genus, closely related to par-voviruses from diverse avian species, whereas BFDV was grouped with strains from Australian cockatoos and other nonpsittacine birds, suggesting potential cross-species transmission. These findings contribute to a deeper understanding of the genetic diversity and evolutionary dynamics of these viral pathogens in bird populations, underscoring the importance of ongoing surveillance to evaluate their ecological and veterinary impacts.

Viral diseases pose significant threats to aquaculture industries worldwide, including the Australian fish and prawn farming sectors, which contribute over AUD 1.6 billion annually to the national economy. The Australian aquaculture industry relies heavily on wild-caught broodstock for seedstock production, introducing substantial and unprecedented biosecurity risks. This systematic review consolidates current knowledge on the viral pathogens affecting key Australian fish and prawn species, their economic impacts, and the biosecurity measures implemented for mitigation. Notably, viral outbreaks have led to losses exceeding AUD 100 million in some sectors, highlighting the urgent need for improved management. Existing biosecurity strategies, including surveillance systems, molecular diagnostics, and pathogen exclusion protocols, are critically assessed for their effectiveness. Emerging approaches such as genetic resistance breeding, advanced vaccination technologies, and integrated risk management frameworks are also explored. Key knowledge gaps, particularly in the context of emerging viral pathogens and their ecological interactions under changing environmental conditions, are identified as priority areas for future research. This review emphasises the necessity of adopting a multidisciplinary approach to enhance the resilience of Australian aquaculture, advocating for stronger biosecurity frameworks and innovative technologies to mitigate the escalating risks posed by viral diseases.