Transboundary and Emerging Diseases最新文献

The NS1 influenza protein of influenza A virus is a viral nonstructural protein encoded by the NS gene segment that has multiple accessory functions during viral infection. In recent years, the major role ascribed to NS1 has been its inhibition of host immune responses, especially the limitation of both interferon (IFN) production and the antiviral effects of IFN-induced protein. We isolated an equine influenza virus with a naturally truncated NS1 gene in our previous study. In this current research, we inserted this partially truncated NS gene into the H₃N₂ canine influenza virus using reverse genetics to develop a live attenuated vaccine strain. To evaluate whether the developed strain is suitable as a live vaccine candidate, we compared its replication kinetics with wild-type virus in MDCK cells and specific pathogen-free eggs. Additionally, we investigated host antiviral gene expression, viral replication in the respiratory system, and associated lung tissue damage in mice experiments. To confirm the efficacy of the vaccine candidate, we evaluated the immunogenicity and protectivity of the developed vaccine strain against canine influenza H₃N₂, compared with a commercial inactivated vaccine. Through these experiments, it was confirmed that the naturally truncated NS1 inserted virus has sufficient potential as a live vaccine candidate, and we hopefully expect that this study would make a great contribution to the development of a live vaccine for canine influenza H₃N₂.

Lumpy skin disease (LSD), a transboundary infectious disease, negatively impacts cattle health and production. The first LSD outbreaks were reported in India in 2019, and since then, LSD spread to over 15 states, including Uttar Pradesh. This study evaluated LSD cases reported by veterinarians in Uttar Pradesh, India, during 2022. Using scan statistics, Poisson models that accounted for the background cattle population were constructed to identify spatial, temporal, and space–time clusters. A negative binomial regression model was built to assess the impact of temperature and humidity on the incidence rate (IR) of LSD. A total of 112,226 cases across 33 districts were reported in 2022. A purely temporal cluster with higher-than-expected LSD rates was identified between August and October 2022. Several purely spatial clusters were identified in the western part of the state. A primary space–time cluster was detected in west Utter Pradesh between August and October 2022 that overlapped with the spatial clusters. The secondary cluster occurred between September and October 2022 in the eastern part of the state. A rise in humidity (incidence rate ratio (IRR) = 1.39; 95% CI: 1.30–1.49) and temperature (IRR = 1.16; 95% CI: 1.06–1.27) increased the IR of LSD, suggesting a seasonality of the outbreaks. The results of this study can aid animal health authorities in developing effective LSD prevention, surveillance, and control strategies among cattle in India.

The problem of zoonoses diseases is a global public and veterinary health concern. Globally coordinated and well-established research efforts are essential to successfully fighting and reducing the health burden of zoonoses. In our study area, the interplay of intense livestock animals, agricultural activities, and poor health services characterized the high risks of zoonotic diseases. Thus, people suffer from easily preventable diseases with hygiene and good-quality food. The main objectives of this study were to: (i) evaluate the knowledge, attitude, and prevention practices of people handling farm animals and their products toward common zoonotic diseases; and (ii) estimate the associated risk factors influencing their knowledge, attitude, and prevention practices. A questionnaire-based cross-sectional study was conducted from December 2021 to August 2022. A simple random sampling technique was followed to select respondents. Multivariable logistic regression model analysis was conducted using STATA version 14. The overall level of knowledge, attitude, and prevention practice for the major zoonotic disease was 52.5%, 68.6%, and 39.4%, respectively. Rabies, tuberculosis, taeniasis, anthrax, and brucellosis were the major zoonotic diseases selected by respondents in the study areas. The age of respondents, training status, educational status, and farm location were significantly (P  < 0.05) associated with the level of knowledge and prevention practice against zoonotic diseases. This study revealed that the level of knowledge, attitude, and prevention practices for major zoonotic diseases in Bahir Dar City were relatively poor. Therefore, a concerted effort among various government and nongovernment stakeholders, including veterinarians, public health officials, and environmental experts, is needed to create and raise awareness among livestock producers about the transmission and control methods and the economic and public health importance of zoonotic diseases.

High pathogenicity avian influenza (HPAI) has impacted poultry and wild birds globally. The number of H5 HPAI virus (HPAIV) infection cases in wild birds in Hokkaido (Northern Japan) was high in the last two seasons, contributing to virus spillover to resident birds and poultry. Therefore, H5 HPAIVs in birds and mammals in Hokkaido in winter 2022–2023 and 2023–2024 were monitored and viruses were phylogenetically, antigenically, and pathogenetically characterized. Thirty HPAIV isolates were subtyped and pathotyped by sequencing the hemagglutinin (HA) gene of viruses. Phylogenetic analysis of the HA gene revealed that all isolated HPAIVs were categorized into clade 2.3.4.4b and divided into three groups (G2b, G2c, and G2d). Most isolates belonging to subgroup G2d clustered with isolates in winter 2021–2022 in Hokkaido. The other isolates were categorized into two subgroups, G2b and G2c, mainly composed of isolates in Honshu Island in winter 2021–2022 and 2022–2023, respectively. Two H5 HPAIVs isolated in Eastern Russia in spring and autumn 2022 were genetically close to most Hokkaido isolates (G2d), and a virus isolated in Hokkaido in November 2023 was also grouped in subgroup G2d. Further analysis of all eight gene segments identified six types of gene constellations. Cross-hemagglutination inhibition test indicated that the antigenicity of H5 HPAIVs isolated in the last several seasons was similar within them but slightly different from that in the 2010s. Three chicken breeds were intranasally challenged with four representative isolates to assess their pathogenicity. All chickens except one broiler chicken were dead until 5-day postchallenge with different pathogenicity of these viruses. The pathogenicity of one HPAIV strain was significantly lower in broiler chickens than in layer chickens. The mixture of multiple characteristics of HPAIVs in Hokkaido was confirmed by bird migration routes. Thus, many HPAIVs can be brought and scattered anywhere on Earth.

Basic reproduction number (R₀) is a mathematical expression used in epidemiology to address expected number of secondary cases. R₀ helps to predict outbreak diffusion and preventive measures. As African swine fever (ASF) is a viral infectious disease, there are significant studies related to R₀ of the ASF outbreak, but most of them are investigated in a zonal and geospecific boundary. This study explores the general overview of African swine fever virus (ASFV) R₀ based on existing literature and examines for the global scale using a doubling time approach using wild boar outbreaks. Further, a qualitative mental model is developed to explore the ASF disease dynamics. It was found that the average R₀ was 3.56 from existing literature. Based on the global scenario, ASFV spread in wild boar was above the threshold line (R₀ ≥ 1). The recent growth trend (R₀ = 5.87) flagging the very high risk. ASFV is threatening the world. The qualitative mental model highlighted the veterinary services as awareness and R&D support are highlighted as the control measures. This study provides a reference to researchers and veterinarians in setting strategies of developing preventive measures and highlights the importance of awareness programs and R&D support for mitigating the ASFV spread.

Village poultry plays a vital role in providing essential nutrition and income for rural communities in Africa. In this context, poultry are often traded through live bird markets (LBMs), which serve as central trading hubs where producers connect with traders and consumers, facilitating the flow of poultry products along the value chain. While they serve as important trading hubs, these markets create an environment where avian pathogens, like Newcastle disease virus (NDV) and avian influenza virus, can easily emerge and spread. Improving our understanding of the epidemiology of NDV in LBMs is important for assessing disease risks and identifying factors that contribute to its persistence. Local chickens at the Mawenzi LBM in Morogoro municipality were surveyed for NDV presence, its temporal and spatial distribution, and risk factors for NDV infection. Twenty-three percent of 659 local chickens sampled over a 1-year period were positive for NDV based on PCR. Increased odds of NDV infection were identified in chickens that had been in the market for 2 or more days prior to sampling and during the period extending from August through October. Four significant spatiotemporal clusters of NDV-positive chickens encompassing 13 villages were detected between August and October 2020, illustrating geographic hotspots of infection when NDV was most prevalent. Similar to the other LBMs, this market had enclosures with high densities of birds of mixed species, limited biosecurity, and the presence of birds with observable illness. Bird traders who source the chickens from the villages, described long transit times in mixed enclosures with limited sanitation practices and without consideration of sick birds or vaccination status prior to arriving at the LBM. This study highlights the need to invest in improvements to infrastructure and biosecurity for LBMs as well as training opportunities for increasing traders’ knowledge on hygiene and sanitation practices, animal welfare, and poultry biosecurity measures.

Muscovy duck-origin goose parvovirus (MDGPV) is a new virus resulting from the natural recombination of Muscovy duck parvovirus (MDPV) and goose parvovirus (GPV). Previously identified MDGPV strains were found to have two recombination regions, one in the P9 promoter to the NS region and one in the VP3 gene, or only one recombination in the VP3 gene. In 2022, a novel strain of MDGPV known as 2022FZ was identified from China’s mainland. Complete genome sequence analysis showed that there were three recombination regions in this strain: one located in the P9 promoter-NS (425–612 nt) region, one in the NS2 (1,483–1,824 nt) region, and one in the VP3 (3,124–4,248 nt) region, respectively. The recombination regions in the P9 promoter-NS, NS2, and VP3 genes were substituted with the relevant GPVs sequences, whereas the MDPV virulent strain served as the skeleton in this instance. In addition, the 2022FZ strain had multiple unique aa mutations in the NS protein and the VP protein. The Muscovy duckling challenge test showed that MDGPV-2022FZ is less pathogenic to Muscovy ducklings than two recombinant or sole recombinant MDGPV strains. For the first time, our study identified a three-region recombinant MDGPV strain and detected the novel recombination event in the NS2 gene. These results contribute to our understanding of the pathogenicity and genetic diversity of duck parvovirus.

The H3 influenza viruses are widespread in domestic poultry but have been ignored because their pathogenicity in poultry is low. Three human infections with H3N8 influenza viruses have been reported in China since 2022, raising public concern. Here, we comprehensively analyzed 30 H3 subtype avian influenza viruses isolated from live poultry markets in China between 2021 and 2022. Genetic and phylogenetic analyses showed that the H3 viruses have undergone frequent reassortment and have formed complex genotypes. Notably, the viruses that caused human infections in 2022–2023 were highly homologous to the H3N8 viruses circulating in poultry in 2022, with internal genes derived from the H9N2 viruses. The analysis of chicken infections indicated that the novel H3N8 viruses were more infectious in chickens than those that do not carry H9N2 genes, whereas the H3 viruses detected in China in 2021–2022 showed low pathogenicity in mice. Our findings suggest that the novel H3N8 viruses bearing internal H9N2 genes have adapted to and circulated in chickens and pose a threat to human health. These results highlight the need for continued surveillance of the H3 influenza viruses and their impact on the poultry industry.

Human brucellosis (HB) remains a significant public health concern in China. This study aimed to investigate the long- and short-term asymmetric impacts of meteorological variables on HB and develop an early prediction system. Monthly data on HB incidence and meteorological variables were collected from 2005 to 2020. The study employed the autoregressive distributed lag (ARDL) and nonlinear ARDL (NARDL) to analyze the long- and short-term effects of climate variables on HB. Subsequently, the data were split into training (from January 2005 to December 2019) and testing parts (from January to December 2020) to develop and validate the forecasting accuracy of both models. During 2005–2020, there were 34,993 HB cases (2.03 per 100,000 persons) and there was an overall rising trend (average annual percentage change = 21.18%, 95%CI 18.36%–26.01%) in HB incidence, peaked in May and troughed in December per year. A 1 m/s increment and decrement in differenced (Δ) average wind velocity (AWV) contributed to 73.8% and 87.5% increases in ΔHB incidence, respectively (Wald long-run asymmetry test (WLR) = 1.17, P = 0.25). A 1 hr increment and decrement in Δ(average relative humidity) contributed to both 3.1% increases in ΔHB incidence (Wald short-run asymmetry test = 3.01, P = 0.003). Average temperature (AT) (P < 0.001) and average air pressure (P = 0.012) played a long-run linear impact on HB. Δ(aggregate precipitation) (WLR = 1.76, P = 0.08) and Δ(aggregate sunshine hours) (WLR = 0.07, P = 0.94) did not have a significant long-term asymmetric impact on Δlog(HB). ΔΔAT(+) and ΔΔAWV(−) at a 1-month lag had a meaningful short-run effect on Δlog(HB). In the forecasting aspect, the NARDL produced significantly smaller error rates compared to the ARDL. Weather variability played significant long- and short-run asymmetric roles in HB incidence. The NARDL by integrating climatic variables could accurately capture the dynamic structure of HB epidemic, meaning that meteorological variables should be integrated into the public health intervention plan for HB.

The continued worldwide increase in pet ownership has significantly boosted the growth of the pet food industry accompanied by new food safety risks and challenges. This study was designed to determine the occurrence and molecularly characterize multidrug-resistant (MDR) Enterobacterales in pet food. Eighty-six (86) packages of dry and wet pet food purchased in different retail stores were screened for carbapenem-resistant Enterobacterales (CRE). Antimicrobial susceptibility testing was performed by agar dilution technique using EUCAST/BrCAST recommendations. Blue-Carba test was further used to screen for carbapenemase-producing isolates. Isolated CRE strains were identified at the species level using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS). Detection of carbapenemase-encoding genes was carried out by PCR, Sanger sequencing, and whole genome sequencing (WGS). A total of 15 (17.4%) MDR-CRE (Escherichia coli (n = 2), Enterobacter cloacae (n = 10), Leclercia adecarboxylata (n = 2), and Cronobacter spp. (n = 1)) were isolated from 86 pet food samples. In addition to being resistant to beta-lactams, the Gram-negative bacterial isolates were also resistant to aminoglycosides, fluoroquinolones, and tigecycline. Interestingly, two carbapenem-resistant E. coli isolates harboured bla_KPC-2 gene. WGS analysis of the two bla_KPC-2-producing E. coli isolates revealed that they both belong to ST648 and serotype O153:H2 group. The genetic context of the bla_KPC-2 showed that they were carried by an IncN plasmid on a Tn4401b transposon element. To the best of our knowledge, this is the first description of bla_KPC-2-harbouring E. coli ST648 pathogens in pet food. The detection of bla_KPC-2-harbouring E. coli ST648 pandemic high-risk lineage in pet food is worrisome and a serious “One Health” issue. Therefore, pet food should be considered as a potential vehicle for the transmission of MDR pathogens to companion animals, and a risk factor for the dissemination of these bacterial pathogens to pet animals and their human guardians.