First report of molecular epidemiology and phylogenetic characteristics of feline herpesvirus (FHV-1) from naturally infected cats in Kunshan, China.

BACKGROUND: Feline herpesvirus type 1 (FHV-1) is a life threatening highly contagious virus in cats and typically causes upper respiratory tract infections as well as conjunctival and corneal ulcers. Genetic variability could alter the severity of diseases and clinical signs. Despite regular vaccine practices against FHV-1 in China, new FHV-1 cases still commonly occur. The genetic and phylogenetic characteristics of FHV-1 in Kunshan city of China has not been studied yet. Therefore, this study was planned to investigate the prevalence, molecular characteristics of circulating strains, and phylogenetic analyses of FHV-1. This is the first report of molecular epidemiology and phylogenetic characteristics of FHV-1 from naturally infected cats in Kunshan, China. METHODS: The occulo-nasal swabs were collected from diseased cats showing respiratory distress, conjunctivitis, and corneal ulcers at different veterinary clinics in Kunshan from 2022 to 2023. Clinical data and general information were recorded. Swab samples were processed for preliminary detection of FHV-1. Thymidine kinase (TK), glycoprotein B (gB) and glycoprotein D (gD) genes were sequenced and analyzed to investigate genetic diversity and evolution of FHV-1. RESULTS: The FHV-1 genome was detected in 43 (43/200, 21.5%) samples using RT-PCR targeting the TK gene. Statistical analysis showed a significant correlation between age, vaccination status and living environment (p < 0.05) with FHV-1 positivity, while a non-significant correlation was observed for FHV-1 positivity and sex of cats (p > 0.05). Additionally, eight FHV-1 positive cats were co-infected with feline calicivirus (8/43,18.6%). FHV-1 identified in the present study was confirmed as FHV-1 based on phylogenetic analyses. The sequence analyses revealed that 43 FHV-1 strains identified in the present study did not differ much with reference strains within China and worldwide. A nucleotide homology of 99-100% was determined among gB, TK and gD genes nucleotide sequences when compared with standard strain C-27 and vaccine strains. Amino acid analysis showed some amino acid substitutions in TK, gB and gD protein sequences. A potential N-linked glycosylation site was observed in all TK protein sequences. Phylogenetic analyses revealed minor variations and short evolutionary distance among FHV-1 strains detected in this study. CONCLUSIONS: Our findings indicate that genomes of 43 FHV-1 strains are highly homogenous and antigenically similar, and the degree of variation in major envelope proteins between strains is low. This study demonstrated some useful data about prevalence, genetic characteristics, and evolution of FHV-1 in Kunshan, which may aid in future vaccine development.

Molecular epidemiology and phylogenetic analysis of feline calicivirus in Kunshan, China.

Feline calicivirus (FCV) is a highly contagious virus in cats, which typically causes respiratory tract and oral infections. Despite vaccination against FCV being a regular practice in China, new FCV cases still occur. Antigenic diversity of FCV hinders the effective control by vaccination. This is first report which aims to investigate the molecular epidemiology and molecular characteristics of FCV in Kunshan, China. The nasopharyngeal swabs were collected from cats showing variable clinical signs from different animal clinics in Kunshan from 2022 to 2023. Preliminary detection and sequencing of the FCV capsid gene were performed to study genetic diversity and evolutionary characteristics. FCV-RNA was identified in 52 (26%) of the samples using RT-PCR. A significant association was found between FCV-positive detection rate, age, gender, vaccination status and living environment, while a non-significant association was found with breed of cats. Nucleotide analysis revealed two genotypes, GI and GII. GII predominated in Kunshan, with diverse strains and amino acid variations potentially affecting vaccination efficacy and FCV detection. Notably, analysis pinpointed certain strains' association with FCV-virulent systemic disease pathotypes. This investigation sheds light on FCV dynamics, which may aid in developing better prevention strategies and future vaccine designs against circulating FCV genotypes.

Molecular epidemiology and characteristics of respiratory syncytial virus among hospitalized children in Guangzhou, China.

BACKGROUND: Human respiratory syncytial virus (RSV) is a leading cause of acute lower respiratory tract infection and hospitalization, especially in children. Highly mutagenic nature and antigenic diversity enable the RSV to successfully survive in human population. We conducted a molecular epidemiological study during 2017-2021 to investigate the prevalence and genetic characteristics of RSV. METHODS: A total of 6499 nasopharyngeal (NP) swabs were collected from hospitalized children at Department of Pediatrics, Guangdong Provincial Hospital of Traditional Chinese Medicine, Guangzhou, Guangdong, China. All NP swab specimens were preliminary screened for common respiratory viruses and then tested for RSV using specific PCR assays. Partial G genes of RSV were amplified for phylogenetic analysis and genetic characterization. RESULTS: The overall detection rate for common respiratory viruses was 16.12% (1048/6499). Among those, 405 specimens (6.20%, 405/6499) were found positive for RSV. The monthly distribution of RSV and other respiratory viruses was variable, and the highest incidence was recorded in Autumn and Winter. Based on the sequencing of hypervariable region of G gene, 93 RSV sequences were sub-grouped into RSV-A (56, 60.2%) and RSV-B (37, 39.8%). There was no coinfection of RSV-A and RSV-B in the tested samples. Phylogenetic analysis revealed that RSV-A and RSV-B strains belonged to ON1 and BA9 genotypes respectively, indicating predominance of these genotypes in Guangzhou. Several substitutions were observed which may likely change the antigenicity and pathogenicity of RSV. Multiple glycosylation sites were noticed, demonstrating high selection pressure on these genotypes. CONCLUSION: This study illustrated useful information about epidemiology, genetic characteristics, and circulating genotypes of RSV in Guangzhou China. Regular monitoring of the circulating strains of RSV in different parts of China could assist in the development of more effective vaccines and preventive measures.

Assessing the nonlinear association of environmental factors with antibiotic resistance genes (ARGs) in the Yangtze River Mouth, China.

The emergence of antibacterial resistance (ABR) is an urgent and complex public health challenge worldwide. Antibiotic resistant genes (ARGs) are considered as a new pollutant by the WHO because of their wide distribution and emerging prevalence. The role of environmental factors in developing ARGs in bacterial populations is still poorly understood. Therefore, the relationship between environmental factors and bacteria should be explored to combat ABR and propose more tailored solutions in a specific region. Here, we collected and analyzed surface water samples from Yangtze Delta, China during 2021, and assessed the nonlinear association of environmental factors with ARGs through a sigmoid model. A high abundance of ARGs was detected. Amoxicillin, phosphorus (P), chromium (Cr), manganese (Mn), calcium (Ca), and strontium (Sr) were found to be strongly associated with ARGs and identified as potential key contributors to ARG detection. Our findings suggest that the suppression of ARGs may be achieved by decreasing the concentration of phosphorus in surface water. Additionally, Group 2A light metals (e.g., magnesium and calcium) may be candidates for the development of eco-friendly reagents for controlling antibiotic resistance in the future.

Metagenomic analysis of endemic viruses in oral secretions from Chinese pigs.

BACKGROUND: Pigs are unique reservoirs for virus ecology. Despite the increased use of improved biosecurity measures, pig viruses readily circulate in Chinese swine farms. OBJECTIVES: The main objective of this study was to examine archived swine oral secretion samples with a panel of pan-species viral assays such that we might better describe the viral ecology of swine endemic viruses in Chinese farms. METHODOLOGY: Two hundred (n = 200) swine oral secretion samples, collected during 2015 and 2016 from healthy pigs on six swine farms in two provinces in China, were screened with molecular pan-species assays for coronaviruses (CoVs), adenoviruses (AdVs), enteroviruses (EVs), and paramyxoviruses (PMV). Samples were also screened for porcine circovirus (PCV) 3, porcine reproductive and respiratory syndrome virus (PRRSV) and influenza A virus (IAV). RESULTS: Among 200 swine oral secretion samples, 152 (76.0%) were found to have at least one viral detection. Thirty-four samples (17%) were positive for more than one virus, including 24 (70.5%) with dual detection and 10 (29.5%) with triple detection. Seventy-eight (39.0%) samples were positive for porcine AdVs, 22 (11.0%) were positive for porcine CoVs, 21 (10.5%) were positive for IAVs, 13 (6.5%) were positive for PCV, 7 (3.5%) were positive for PMV, six (3.0%) were positive for PRRSV and five (2.5%) were positive for porcine EV. CONCLUSION: Our findings underscore the high prevalence of numerous viruses among production pigs in China and highlight the need for routine, periodic surveillance for novel virus emergence with the goal of protecting pigs.

Current scenario of viral diseases and vaccination strategies of cattle in Turkey.

The dairy and meat industry has rapidly developed in the last decade in Turkey and is playing a key role in supplying animal proteins for human consumption. Viral pathogens continue to threaten the dairy and meat industry leading to serious economic losses worldwide, including Turkey. The Turkish cattle industry has been vulnerable to the spread of viral diseases within the country in the continent. Combating animal diseases is crucial for the economy of Turkey. A good cattle health management policy may reduce the direct losses associated with viral diseases and thereby lead to increase in export of animals and animal products. Countries that are unable to combat animal diseases remain excluded from international trade. Control and eradication of cattle diseases require the availability of effective and practical interventions including vaccination and biosecurity measures. This review summarises the currently available information about viral diseases in cattle in Turkey and emphasizes the need for disease monitoring and research, along with implementation of disease control measures to mitigate economic losses to farmers and the country. The information presented here can be of great value in the research, prevention, and control of cattle diseases.

Molecular typing of human adenoviruses among hospitalized patients with respiratory tract infections in a tertiary Hospital in Guangzhou, China between 2017 and 2019.

BACKGROUND: Human Adenoviruses (HAdVs) cause a wide array of illnesses in all age groups. They particularly cause frequent morbidity among children. In China, human adenovirus types 3, 4, 7, 11, 14, 21, and 55 have caused at least seven outbreaks since 2000. However, limited studies are available regarding the epidemiological patterns and diversity of HAdVs types among hospitalized patients with respiratory tract infections (RTIs). METHODS: To understand the epidemiology and subtype distribution of HAdV infections associated with RTIs in China, nasal swab (NS) clinical samples were collected from 4129 patients in a Guangzhou hospital between August 2017 and October 2019. PCR, sequencing, and phylogenetic analysis were performed on these specimens to identify HAdV subtypes. RESULTS: HAdV was successfully sequenced in 99 (2.4%) of the 4129 NS specimens, with the highest HAdV prevalence (6.3%) found in children between the ages of 5 and 10 years. Among HAdV-positive specimens, the most prevalent genotypes identified were HAdV-B3 (55.6%) and HAdV-B7 (25.3%). The most common symptoms in the HAdV-infected patients were fever (100%), cough (80.8%), and rhinorrhea (71.8%). HAdV infections were detected throughout the year with a relatively higher prevalence in summer. CONCLUSION: All ages suffer adenovirus infections, but young children are at the greatest risk. This study data demonstrates that at least three species of HAdVs (species B, C, and E) are circulating in Guangzhou City, China. As antiviral therapies and type-specific vaccines become available, such epidemiological data will be useful in guiding therapy and public health interventions.

Retraction notice to "Mycoplasma synoviae vaccine modifies virus shedding and immune responses of avian influenza (H9N2) infection in commercial layers" [Poult. Sci. 96 (2017) 3086-3095].

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). The authors retract the above paper due to: 1) conflict of interest among the authors; and 2) addition of co-author Dr. Muhammad Younus without his knowledge or permission. The authors apologize for these two grave mistakes.

Characterisation of Fowl Adenovirus (FAdV-8b) Strain Concerning the Geographic Analysis and Pathological Lesions Associated with Inclusion Body Hepatitis in Broiler Flocks in Turkey.

INTRODUCTION: Fowl adenovirus can cause important diseases in chickens such as inclusion body hepatitis, hepatitis hydropericardium syndrome, and gizzard erosion and ulceration. Inclusion body hepatitis has been regularly reported from many countries. This is the first case report from Turkey, describing an outbreak of inclusion body hepatitis in broiler farms due to fowl adenovirus-8b (FAdV-8b). MATERIAL AND METHODS: Broiler flocks with mortality about 10% were visited in Turkey, and necropsy was performed on dead birds. Samples were subjected to PCR assay to detect FAdV and other viral pathogens. After sequencing, phylogenetic analysis was performed and the nucleotide sequences of hexon genes were compared with the FAdV sequences data available in GenBank. RESULTS: Clinical signs such as anorexia, depression, ruffled feathers, huddling, and greenish diarrhoea were observed. Mortality started at the 8th day of age and ranged from 10% to 14%. Necropsy showed severe hepatitis, jaundice, and pancreatitis. The main necropsy findings included a pale, enlarged, haemorrhagic, and friable liver along with swollen and haemorrhagic kidneys and spleen. PCR and sequence analysis revealed the presence of fowl adenovirus serotype 8b (FAdV-E). CONCLUSION: This is the first report on characterisation and the pathological lesions associated with FAdV in broilers in Turkey. Our findings suggest that FAdV strains could be an emerging pathogen in Turkish broilers and could actively contribute to hepatitis and immunosuppression.

First report of influenza D virus infection in Turkish cattle with respiratory disease.

Bovine respiratory infections are the most economically important diseases affecting the cattle industry worldwide including Turkey. Influenza D virus (IDV) could play an important role to trigger bovine respiratory disease (BRD) complex. Since, there is no data about the presence and genotypes of IDV in Turkish cattle herds; this study was performed to investigate IDV in cattle in Turkey. Animals analyzed in this study were from commercial cattle farms having respiratory disease in calves with significant mortality. Nasal swabs and tissue samples from cattle in Marmara, Inner Anatolia and Aegean region of Turkey were analyzed by real-time RT-PCR assay to detect IDV. Among 76 samples form 12 cattle herds, IDV was detected in 3 cattle in a herd. Sequencing and phylogenetic analysis of partial hemagglutinin esterase fusion (HEF) gene showed that the Turkish strain is 95% identical to its European and US counterparts, which suggest intercontinental spread of the virus. These findings highlight the need for future continuous surveillance on larger scale to determine the distribution pattern and evolution of this novel emerging pathogen in Turkish cattle industry.

Molecular epidemiology of respiratory viruses in commercial chicken flocks in Pakistan from 2014 through to 2016.

BACKGROUND: Viral diseases are a matter of great concern for poultry farmers in Pakistan. Multiple common viral respiratory diseases (CVRDs) cause huge economic losses in the poultry industry. The prevalence of CVRDs in many countries, including Pakistan, is not clearly understood. RESULTS: Incidences of 5 chicken respiratory viruses: avian influenza virus (AIV), Newcastle disease virus (NDV/AAVV-1), infectious bronchitis virus (IBV), avian metapneumovirus (aMPV) and infectious laryngotracheitis virus (ILTV) were assessed on commercial Pakistani farms with respiratory problems from 2014 through to 2016. While AIV and AAVV-1 were frequently detected (16 to 17% of farms), IBV and aMPV were rarely detected (in 3 to 5% of farms) and ILTV was not detected. We characterized H9 AIV of the G1 lineage, genotype VII AAVV-1, GI-13 IBV, and type B aMPV strains with very little genetic variability in the 2-year study period. Co-infections with AIV and AAVV-1 were common and wild type AAVV-1 was detected despite the use of vaccines. Control measures to limit the virus burden in chicken flocks are discussed. CONCLUSIONS: Our data shows that AIV (H9), AAVV-1, IBV and aMPV are prevalent in commercial poultry in Pakistan. Further studies are necessary to assess circulating strains, economic losses caused by infections and coinfections of these pathogens, and the costs and benefits of countermeasures. Furthermore, veterinarians and farmers should be informed of the pathogens circulating in the field and hence advised on the use of vaccines.

Seroprevalence and Risk Factors of Toxoplasma gondii in Wild Birds of Punjab Province, Pakistan.

Toxoplasma gondii is a protozoan parasite of veterinary and human public health importance for which birds act as an intermediate host. No information is available about the epidemiology of T. gondii in wild birds of Pakistan. The present study was designed to determine the seroprevalence and risk factors associated with T. gondii antibodies in wild birds of District Kasur, Punjab Province, Pakistan. A total of 200 wild birds of 28 species were captured from four tehsils (administrative subdistricts of districts) of the district Kasur and their serum samples screened for the presence of T. gondii antibodies using a latex agglutination test (cut-off value: 1:64). Twenty-five (13%) individual birds and 13 (46%) of the bird species were seropositive for T. gondii antibodies. There were statistical differences in T. gondii prevalence between adults and young (15% and 7%, respectively, P=0.001) and healthy and sick (11% and 50%, respectively, P=0.000) while there were not differences between genders, sites, urbanicity, and tehsils. The present study provides evidence of T. gondii antibodies in wild birds of Pakistan.

Pathobiology of Avian avulavirus 1: special focus on waterfowl.

Avian avulaviruses serotype 1 (abbreviated as APMV-1 for the historical name avian paramyxovirus 1) are capable of infecting a wide spectrum of avian species with variable clinical symptoms and outcomes. Ease of transmission has allowed the virus to spread worldwide with varying degrees of virulence depending upon the virus strain and host species. The emergence of new virulent genotypes from global epizootics, and the year-to-year genomic changes in low and high virulence APMV-1 imply that distinct genotypes of APMV-1 are simultaneously evolving at different geographic locations across the globe. This vast genomic diversity may be favoured by large variety of avian species susceptibility to APMV-1 infection, and by the availability of highly mobile wild birds. It has long been considered that waterfowls are not sensitive to APMV-1 and are unable to show any clinical signs, however, outbreaks from the 90's contradict these concepts. The APMV-1 isolates are increasingly reported from the waterfowl. Waterfowl have strong innate immune responses, which minimize the impact of virus infection, however, are unable to prevent the viral shedding. Numerous APMV-1 are carried by domestic waterfowl intermingling with terrestrial poultry. Therefore, commercial ducks and geese should be vaccinated against APMV-1 to minimize the virus shedding and for the prevention the transmission. Genetic diversity within APMV-1 demonstrates the need for continual monitoring of viral evolution and periodic updates of vaccine seed-strains to achieve efficient control and eradication of APMV-1 in waterfowls.

Cloning and Expression of NS3 Gene of Pakistani Isolate Type 2 Dengue Virus.

INTRODUCTION: Dengue is one of the major emerging viral diseases in the world, with dramatic increases in reported cases in the last few decades and annual worldwide occurrence of approximately 390 million infections. It is a highly important mosquito-vectored disease and is a problem in tropical and subtropical areas of the world. The major aim of this study was to clone and express the dengue NS3 gene, in service to its therapeutic importance for the development of stable cell lines. MATERIAL AND METHODS: Blood samples from dengue fever (DF) patients were collected and subjected to PCR amplification of the NS3 gene of dengue virus serotype-2 (DENV-2). The NS3 gene was amplified using gene specific primers and cloned in the TA cloning vectors. RESULTS: The gene was successfully expressed in mammalian expression vector pcDNA3.1. The current finding was different from a previously reported DENV-2 strain replicon constructed in different cells, in which the whole genetic material of the virus was used instead of an active protease gene, and which gave a low yield of replicon expressing cells. CONCLUSION: Recombinant NS3 could be used to produce an antibody that is possibly helpful for developing a single step diagnostic assay to detect the dengue virus NS3 antigen in sera of dengue patients.

Report - Susceptibility of avian pathogenic Escherichia coli from Zoo birds in Indonesia to antibiotics and disinfectants.

Antibiotic resistance in avian pathogenic Escherichia coli (APEC) is a common problem in the Indonesian poultry industry. Zoo birds have been postulated as sentinels, reservoirs, and potential spreaders of antibiotic resistance, although much is still unknown about the strains of zoo birds. Disinfection can reduce the infection burden. However, little is known about the presence of resistance against these products. Sixty one APEC strains were isolated from Indonesian zoo birds. The resistance to different classes of antibiotics as well as the minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) of five disinfectants most often used in the poultry industry was determined. Resistance to tetracycline (42.6%), sulfonamides (24.5%), ampicillin (22.9%), gentamicin (19.6), nalidixic acid (18.03%) and streptomycin (16.3%) was high, but resistance to other tested antibiotics was low and none of the isolates were resistant to extended spectrum beta-lactamase (ESBL) producers. Sixteen strains (26.2%) were found positive for multi drug resistance. The MIC of the disinfectants for the APEC strains showed normal distribution, indicating that there was no acquired resistance. MBCs were similar to MICs using the broth dilution method, showing the bactericidal effect of the disinfectants. Phenotypic resistance to commonly used disinfectants could not be found, indicating that the current use of disinfectants in the zoo and aviaries did not select for resistance. Significantly high resistance rates against commonly used antibiotics in Indonesian zoos is worrisome and indicates that widespread use of antibiotics could have negative implications for animal health and the environment. Proper use of antibiotics and surveillance programs to monitor antimicrobial resistance in pathogenic bacteria are warranted.

Co-infection of turkeys with Escherichia coli (O78) and H6N1 avian influenza virus.

Respiratory diseases are responsible for major economic losses in poultry farms. While in most cases a single pathogen is not alone responsible for the clinical outcome, the impact of co-infections is not well known, especially in turkeys. The purpose of this study was to assess the possible synergism between Escherichia coli (O78) and low pathogenic avian influenza virus (LPAIV, H6N1), in the turkey model. Four-week-old commercial turkeys were inoculated with either H6N1, O78 or both agents simultaneously or three days apart. We have established an experimental infection model of turkeys using aerosolization that better mimics field infections. Birds were observed clinically and swabbed on a daily basis. Necropsies were performed at 4 and 14 days post single or dual inoculation and followed by histological and immunohistochemical analyses. Combined LPAIV/E. coli infections resulted in more severe clinical signs, were associated with higher mortality and respiratory organ lesions (mucous or fibrinous exudative material in lungs and air sacs), in comparison with the groups given single infections (P < 0.05). The time interval or the sequence between H6N1 and E. coli inoculation (none or three days) did not have a significant effect on the outcome of the dual infection and disease although slightly greater (P > 0.05) respiratory signs were observed in turkeys of the E. coli followed by H6N1 inoculated group. Microscopic lesions and immunohistochemical staining supported clinical and macroscopic findings. Efficient virus and bacteria replication was observed in all inoculated groups. E. coli and H6N1 thus exercise an additive or synergistic pathogenic effect in the reproduction of respiratory disease.