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African swine fever virus (ASFV) is endemic to African wild pigs ( Phacochoerus and Potamochoerus ), in which viral infection is asymptomatic, and Ornithodoros soft ticks. However, ASFV causes a lethal disease in Eurasian domestic pigs ( Sus scrofa ). While Sub-Saharan Africa is believed to be the original home of ASFV, publicly available whole-genome ASFV sequences show a strong bias towards p72 Genotypes I and II, which are responsible for domestic pig pandemics outside Africa. To reduce this bias, we hereby describe nine novel East African complete genomes in p72 Genotype IX and present the phylogenetic analysis of all 16 available Genotype IX genomes compared with other ASFV p72 clades. We also document genome-level differences between one specific novel Genotype IX genome sequence (KE/2013/Busia.3) and a wild boar cell-passaged derivative. The Genotype IX genomes clustered with the five available Genotype X genomes. By contrast, Genotype IX and X genomes were strongly phylogenetically differentiated from all other ASFV genomes. The p72 gene region, on which the p72-based virus detection primers are derived, contains consistent SNPs in Genotype IX, potentially resulting in reduced sensitivity of detection. In addition to the abovementioned cell-adapted variant, eight novel ASFV Genotype IX genomes were determined: five from viruses passaged once in primary porcine peripheral blood monocytes and three generated from DNA isolated directly from field-sampled kidney tissues. Based on this methodological simplification, genome sequencing of ASFV field isolates should become increasingly routine and result in a rapid expansion of knowledge pertaining to the diversity of African ASFV at the whole-genome level.

The formation of Campylobacter jeuni biofilms on processing surfaces is a significant concern in poultry processing, contributing to food safety risks. This study focused on assessing the biofilm forming capabilities of 12 field isolates of C. jejuni of different aerotolerance categories on stainless steel surfaces, a prevalent material in poultry processing environments. Working cultures of each isolate were prepared to approximately 6 log CFU/mL and incubated on stainless steel coupons under microaerobic or aerobic conditions at room temperature or 42°C for 72 h. Biofilm attached cells were enumerated using direct plating and biofilm density was measured using a crystal violet assay by measuring the optical density (OD 600 ) a. Data analysis was conducted using the PROC GLIMMIX procedure in SAS 9.4 with a significance level of 0.05. The study revealed a notable interaction between aerotolerance categories and temperature (P < 0.039) impacting the number of biofilms attached C. jejuni cells on stainless steel coupons. All isolates had significantly higher counts when incubated at 42°C compared to room temperature, regardless of oxygen level (P < 0.001). Furthermore, stronger biofilm density was observed at 42°C compared to room temperature, regardless of oxygen level. These findings underscore the influence of temperature on the biofilm forming ability of C. jejuni. The ability of these field isolates to form biofilms under various environmental conditions suggests a heightened potential for surface colonization and increased infection risk in poultry processing facilities., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Malaria treatments resulted in the decline of the deadliest Plasmodium falciparum globally while species, such as P. ovale , infections have been increasingly detected across sub-Saharan Africa. Currently, no experimental drug sensitivity data are available to guide effective treatment and management of P. ovale infections, which is necessary for effective malaria elimination. We conducted a prospective study to evaluate P. ovale epidemiology over 1 year and determined ex vivo susceptibility of the field isolates to existing and lead advanced discovery antimalarial drugs. We report that while P. falciparum dominated both symptomatic and asymptomatic malaria cases, P. ovale in mono or co-infections caused 7.16% of symptomatic malaria. Frontline antimalarials artesunate and lumefantrine inhibited P. ovale as potently as P. falciparum. Chloroquine, which has been withdrawn in Ghana, was also highly inhibitory against both P. ovale and P. falciparum. In addition, P. ovale and P. falciparum displayed high susceptibility to quinine, comparable to levels observed with chloroquine. Pyrimethamine, which is a major drug for disease massive prevention, also showed great inhibition of P. ovale , comparable to effects on P. falciparum. Furthermore, we identified strong inhibition of P. ovale using GNF179, a close analogue of KAF156 imidazolopiperazines, which is a novel class of antimalarial drugs currently in clinical phase II testing. We further demonstrated that the Plasmodium phosphatidylinositol-4-OH kinase (PI4K)-specific inhibitor, KDU691, is highly inhibitory against P. ovale and P. falciparum field isolates. Our data indicated that existing and lead advanced discovery antimalarial drugs are suitable for the treatment of P. ovale infections in Ghana. IMPORTANCE Current malaria control and elimination tools such as drug treatments are not specifically targeting P.ovale . P. ovale can form hypnozoite and cause relapsing malaria. P. ovale is the third most dominant species in Africa and requires radical cure treatment given that it can form liver dormant forms called hypnozoites that escape all safe treatments. The inappropriate treatment of P. ovale would sustain its transmission in Africa where the medical need is the greatest. This is a hurdle for successful malaria control and elimination. Here, we provided experiment data that were lacking to guide P. ovale treatment and disease control policy makers using reference antimalarial drugs. We also provided key experimental data for 2 clinical candidate drugs that can be used for prioritization selection of lead candidate's identification for clinical development., Competing Interests: The authors declare no conflict of interest.

Phytophthora infestans is the oomycete that causes potato blight, an important disease. The potato spindle tuber viroid (PSTVd) is a dangerous pathogen of many plants, including potato. We have previously shown that PSTVd can be transmitted from infected potato plants into the Ph. infestans mycelium, replicated within the mycelium, and then transmitted to other potato plants upon their infection with Ph. infestans in laboratory conditions. The objective of this work was to check the hypothesis that PSTVd transmission, preservation, and replication in Ph. infestans are possible to occur in natural conditions during long-term coevolution of the host and pathogen in the Solanum spp.-Ph. infestans system. A screening test for PSTVd was performed in 111 natural Ph. infestans isolates obtained from potato plants, which represented various cultivars, had signs of potato blight, and were collected from industrial potato fields of the Moscow, Vologda, and Bryansk regions and breeding and variety test plots of the St. Petersburg and Moscow regions in 2020 and 2022. Using RT-PCR with PSTVd-specific primers, 42 Ph. infestans isolates collected in 2020 were tested after five passages and 69 Ph. infestans isolates collected in 2022, after a single passage on rye agar. Diagnostic amplicons were detected in 8 and 50 isolates, respectively. Some of the amplicons were visually assessed as minor amplification products, apparently resulting from nonspecific priming on a host Ph. infestans gene, which codes for a hypothetical protein-coding mRNA in Ph. infestans and other oomycetes. Eight amplicons were sequenced to verify the PSTVd presence in Ph. infestans isolates. Three amplicons corresponded to the complete PSTVd genome and five, to its part (~260 bp). The nucleotide sequences of cloned amplification products were identified to species in the BLAST system and deposited in GenBank. The amplicons obtained with the PSTVd-specific primers were identified as PSTVd sequences in all Ph. infestans isolates examined. The majority of the nucleotide sequences were phylogenetically related to BLAST sequences of PSTVd strains originating from Russia; several strains showed similarity to strains from other countries (France, China, and West African countries). The results demonstrate that PSTVd was for the first time detected in natural (field) Ph. infestans isolates and offer new opportunities for studying the intricate multilevel host-parasite interactions., (© 2023. Pleiades Publishing, Ltd.)

Malaria is a life-threatening parasitic disease caused by members of the genus Plasmodium. The development and spread of drug-resistant strains of Plasmodium parasites represent a major challenge to malaria control and elimination programmes. Evaluating genetic polymorphism in a drug target improves our understanding of drug resistance and facilitates drug design. Approximately 450 and 19 whole-genome assemblies of Plasmodium falciparum and Plasmodium vivax, respectively, are currently available, and numerous sequence variations have been found due to the presence of single nucleotide polymorphism (SNP). In the study reported here, we analysed global SNPs in the malaria parasite aminoacyl-tRNA synthetases (aaRSs). Our analysis revealed 3182 unique SNPs in the 20 cytoplasmic P. falciparum aaRSs. Structural mapping of SNPs onto the three-dimensional inhibitor-bound complexes of the three advanced drug targets within aaRSs revealed a remarkably low mutation frequency in the crucial aminoacylation domains, low overall occurrence of mutations across samples and high conservation in drug/substrate binding regions. In contrast to aaRSs, dihydropteroate synthase (DHPS), also a malaria drug target, showed high occurrences of drug resistance-causing mutations. Our results show that it is pivotal to screen potent malaria drug targets against global SNP profiles to assess genetic variances to ensure success in designing drugs against validated targets and tackle drug resistance early on., (© 2022. The Author(s).)

The increased virulence of infectious bursal disease virus (IBDV) is a threat to the chicken industry. The construction of novel herpesvirus of turkey-vectored (HVT) vaccines expressing VP2 of virulent IBDV may be a promising vaccine candidate for controlling this serious disease in chickens. We generated a novel infectious clone of HVT Fc-126 by inserting mini-F sequences in lieu of the glycoprotein C (gC) gene. Based on this bacterial artificial chromosome (BAC), a VP2 expression cassette containing the pMCMV IE promoter and a VP2 sequence from the virulent IBDV NJ09 strain was inserted into the noncoding area between the UL55 and UL56 genes to generate the HVT vector VP2 recombinant, named HVT-VP2-09. The recovered vectored mutant HVT-VP2-09 exhibited higher titers ( p = 0.0202 at 36 h) or similar growth kinetics to the parental virus HVT Fc-126 ( p = 0.1181 at 48 h and p = 0.1296 at 64 h). The high reactivation ability and strong expression of VP2 by HVT-VP2-09 in chicken embryo fibroblasts (CEFs) were confirmed by indirect immunofluorescence (IFA) and Western blotting. The AGP antibodies against IBDV were detected beginning at 3 weeks post-inoculation (P.I.) of HVT-VP2-09 in 1-day-old SPF chickens. Seven of ten chickens immunized with HVT-VP2-09 were protected post-challenge (P.C.) with the virulent IBDV NJ09 strain. In contrast, all chickens in the challenge control group showed typical IBD lesions in bursals, and eight of ten died P.C. In this study, we demonstrated that (i) a novel HVT BAC with the whole genome of the Fc-126 strain was obtained with the insertion of mini-F sequences in lieu of the gC gene; (ii) HVT-VP2-09 harboring the VP2 expression cassette from virulent IBDV exhibited in vitro growth properties similar to those of the parental HVT virus in CEF cells; and (iii) HVT-VP2-09 can provide efficient protection against the IBDV NJ09 strain.

Malaria elimination urgently needs novel antimalarial therapies that transcend resistance, toxicity, and high costs. Our multicentric international collaborative team focuses on developing multistage antimalarials that exhibit novel mechanisms of action. Here, we describe the design, synthesis, and evaluation of a novel multistage antimalarial compound, 'Calxinin'. A compound that consists of hydroxyethylamine (HEA) and trifluoromethyl-benzyl-piperazine. Calxinin exhibits potent inhibitory activity in the nanomolar range against the asexual blood stages of drug-sensitive (3D7), multidrug-resistant (Dd2), artemisinin-resistant (IPC4912), and fresh Kenyan field isolated Plasmodium falciparum strains. Calxinin treatment resulted in diminished maturation of parasite sexual precursor cells (gametocytes) accompanied by distorted parasite morphology. Further, in vitro liver-stage testing with a mouse model showed reduced parasite load at an IC 50 of 79 nM. A single dose (10 mg/kg) of Calxinin resulted in a 30% reduction in parasitemia in mice infected with a chloroquine-resistant strain of the rodent parasite P. berghei . The ex vivo ookinete inhibitory concentration within mosquito gut IC 50 was 150 nM. Cellular in vitro toxicity assays in the primary and immortalized human cell lines did not show cytotoxicity. A computational protein target identification pipeline identified a putative P . falciparum membrane protein ( Pf 3D7&#95;1313500) involved in parasite calcium (Ca 2+ ) homeostasis as a potential Calxinin target. This highly conserved protein is related to the family of transient receptor potential cation channels (TRP-ML). Target validation experiments showed that exposure of parasitized RBCs (pRBCs) to Calxinin induces a rapid release of intracellular Ca 2+ from pRBCs; leaving de-calcinated parasites trapped in RBCs. Overall, we demonstrated that Calxinin is a promising antimalarial lead compound with a novel mechanism of action and with potential therapeutic, prophylactic, and transmission-blocking properties against parasites resistant to current antimalarials.

The survival of African swine fever virus (ASFV) on different matrices and its infectivity in wild as well as domestic swine is still a matter of interest. ASFV is resistant to environmental effects; this fact is enhanced by the presence of organic material. Therefore, the aim of this work was to determine the ability of laboratory ASFV to survive in soil at different temperatures (4 and 22 °C) and with and without the presence of blood using culture procedures. The suitability of the procedure for determining the viability and titre of the ASFV field strain by the hemadsorption method was also verified, when a higher decrease in virus infectivity in the case of clay compared with peat was demonstrated. The stability of the virus was clearly temperature-dependent, the infectious virus was detected after 112 days, and the viral DNA was still detected in the matrix 210 days after inoculation in a relatively high and stable concentration (between 10 6 and 10 7 genome equivalents/mL). Based on this knowledge, soil and other environmental samples could provide rapid and reliable information on the disease outbreak and serve as indicators of the risk posed by the affected locality.

The pathogenesis of malaria is largely attributable to the parasite's ability to modulate its cytoadhesion phenotype. This relates to the multigenic families comprising dozens to hundreds of members, whose expression, often mutually exclusive, allows the parasite to vary its adhesive properties and antigenic appearance. This phenomenon is mainly described for the variant surface antigens that the parasite expresses on the infected erythrocyte. In order to decipher these gene expression spectra and identify potential antigenic candidates and/or targets of therapeutic interest, the analysis of the transcriptomes of the parasites directly isolated from patients with well-defined clinical presentation is important. RNA stabilization is an absolute prerequisite for a precise and accurate transcriptome profiling. Immediate stabilization of RNA of biological samples is therefore necessary to prevent degradation by ribonucleases (RNase) or cellular changes. This chapter described methodology for preserving parasite RNA samples from malaria patients in the field for transcriptome studies., (© 2022. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Several members of the Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) family can bind human serum proteins such as IgM and α 2 -macroglobulin (α 2 M). This binding seems to play a role in pathogenesis and immune evasion by improving the avidity of PfEMP1-mediated binding to erythrocyte receptors and/or by masking antibody epitopes in PfEMP1. In this protocol, we describe a flow cytometry-based protocol to evaluate IgM- and α 2 M-binding to intact and unfixed mature-stage IEs. The method can be used for laboratory clones and field isolates., (© 2022. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Antimicrobial resistance and pulsed-field gel electrophoresis (PFGE) genotypes of collected S. enterica ser. Gallinarum isolates were investigated to examine the epidemiological relationship between field outbreak isolates of S. enterica ser. Gallinarum. Thirty S. enterica ser. Gallinarum isolates collected from poultry farms with FT outbreaks from 2013 to 2018 in South Korea were analyzed. All isolates were resistant to at least 3 of the 18 antimicrobials tested and exhibited an MDR phenotype. All isolates showed resistance to streptomycin, sulfisoxazole, and colistin. One isolate was resistant to 9 antimicrobials. The antimicrobial resistance profile, streptomycin-sulfisoxazole-colistin-nalidixic acid-ciprofloxacin-gentamicin (18/30, 60.0%), was the most prevalent. PFGE types were classified into 10 groups with a 100% correlation cutoff in dendrograms for 30 field isolates. The dominant PFGE types were 1 (8/30, 26.7%), 4 (7/30, 23.3%), and 9 (5/30, 16.7%). Interestingly some isolates collected from the same and different companies had the same PFGE type. We reported a high MDR rate in S. enterica ser. Gallinarum isolates. The present study highlights the occurrence of horizontal spread and cyclic contamination of MDR S. enterica ser. Gallinarum within the same company. Furthermore, we showed cross-contamination between different companies. The characterization of these isolates would be helpful in the development of prevention and control strategies for MDR S. enterica ser. Gallinarum infection in South Korea.

Purpose: Malaria continues to be a major health issue globally with almost 85% of the global burden and deaths borne by sub-Saharan Africa and India. Although the current artemisinin derived combination therapies in Ghana are still efficacious against the Plasmodium falciparum ( Pf ) parasite, compounding evidence of artemisinin and amodiaquine resistance establish the need for a full, up-to-date understanding and monitoring of antimalarial resistance to provide evidence for planning control strategies., Materials and Methods: The study was cross-sectional and was conducted during the peak malaria transmission seasons of 2015, 2016, and 2017 in two ecological zones of Ghana. Study participants included children aged 6 months to 14 years. Using ex vivo 4,6-diamidino-2-phenylindole (DAPI) drug sensitivity assay, 330 Pf isolates were used to investigate susceptibility to five antimalarial drugs: chloroquine (CQ), amodiaquine (AMD) dihydroartemisinin (DHA), artesunate (ART) and mefloquine (MFQ)., Results: The pooled geometric mean IC 50 S (GMIC 50 ) of the five drugs against the parasites from Cape Coast and Begoro were 15.5, 42.4, 18.9, 4.6 and 27.3nM for CQ, AMD, DHA, ART, and MFQ, respectively. The GMIC 50 values for CQ (p<0.001), ART (p<0.011) and DHA (p<0.018) were significantly higher for Cape Coast isolates as compared to Begoro isolates. However, GMIC 50 estimates for MFQ (p<0.022) were significantly higher for Begoro isolates. Positive correlations were found between each pair of drugs with the weakest found between MFQ and DHA ( r = 0.34;p<0.001), and the strongest between ART and DHA ( r =0.66; p<0.001)., Conclusion: The parasites showed reduced sensitivities to three (AMD, DHA and MFQ) out of the five drugs assessed. The study also demonstrated the continual return of chloroquine-sensitive parasites after 13 years of its withdrawal as the first-line drug for the treatment of uncomplicated malaria in Ghana. The ex vivo DAPI assay is a reliable method for assessing antimalarial drug sensitivities of Pf field isolates under field settings., Competing Interests: Emma E. Kploanyi reports grants from NIH, during the conduct of the study. The authors report no other potential conflicts of interest in this work., (© 2021 Ofori et al.)

The objectives of this study were to compare the virulence of contemporary infectious laryngotracheitis virus (ILTV) field isolates of classes 9, 10, and 14 in meat and layer chickens, and to evaluate cloacal and oropharyngeal swabs and dust as sample types for ILTV detection. A total of 211 chickens were divided into groups and inoculated with ILTV class 9, 10, or 14, or sham-inoculated via eye drop at 15 or 22 days of age. Chickens were euthanized at 5 and 9 days post-infection. Virulence was assessed by scoring of clinical signs (conjunctivitis, dyspnoea, and demeanour), ILTV genomic copies (GC) in oropharyngeal and cloacal swabs, mortality and microscopic lesions in conjunctiva and trachea. Class 14 caused subclinical infection, while inoculation with class 9 or class 10 resulted in severe clinical signs and microscopic lesions. Compared to class 14 (2.25 ± 0.36 log 10 GC), higher viral load was observed in oropharyngeal swabs of classes 9 (7.86 ± 0.48) and 10 (7.53 ± 0.36), with a higher proportion of positive oropharyngeal and cloacal swabs in the latter groups ( P  < 0.0001). Viral detection in cloacal swabs was delayed at early stages of infection compared to oropharyngeal swabs. Dust samples from class 9- and class 10-inoculated groups showed a trend towards higher GC than that of class 14. Overall, clinical scores, mortality, viral load, and microscopic lesions were similar for classes 9 and 10, but class 9 caused more severe disease in layer chickens than meat chickens. In summary, ILTV classes 9 and 10 exhibited severe virulence, while class 14 exhibited very mild virulence. RESEARCH HIGHLIGHTS Wide variation in the virulence of three field Australian field ILTV strains. Class 9 and class 10 strains were highly virulent, while class 14 was mildly virulent. The highly virulent strains were associated with significantly higher viral genome copies in various sample types than the mildly virulent strain.

Magnaporthe oryzae is the causal agent for the devastating disease rice blast. The avirulence ( AVR ) genes in M. oryzae are required to initiate robust disease resistance mediated by the corresponding resistance ( R ) genes in rice. Therefore, monitoring pathogen AVR genes is important to predict the stability of R gene-mediated blast resistance. In the present study, we analyzed the DNA sequence dynamics of five AVR genes, namely, AVR-Pita1 , AVR-Pik , AVR-Pizt , AVR-Pia , and AVR-Pii , in field isolates of M. oryzae in order to understand the effectiveness of the R genes, Pi-ta , Pi-k , Pi-zt , Pia , and Pii in the Southern U.S. rice growing region. Genomic DNA of 258 blast isolates collected from commercial fields of the Southern UNITED STATES during 1975-2009 were subjected to PCR amplification with AVR gene-specific PCR markers. PCR products were obtained from 232 isolates. The absence of PCR products in the remaining 26 isolates suggests that these isolates do not contain the tested AVR genes. Amplified PCR products were subsequently gel purified and sequenced. Based on the presence or absence of the five AVR genes, 232 field isolates were classified into 10 haplotype groups. The results revealed that 174 isolates of M. oryzae carried AVR-Pita1 , 225 isolates carried AVR-Pizt , 44 isolates carried AVR-Pik , 3 isolates carried AVR-Pia , and one isolate carried AVR-Pii . AVR-Pita1 was highly variable, and 40 AVR-Pita1 haplotypes were identified in avirulent isolates. AVR-Pik had four nucleotide sequence site changes resulting in amino acid substitutions, whereas three other AVR genes, AVR-Pizt , AVR-Pia , and AVR-Pii , were relatively stable. Two AVR genes, AVR-Pik and AVR-Pizt , were found to exist in relatively larger proportions of the tested field isolates, which suggested that their corresponding R genes Pi-k and Pi-zt can be deployed in preventing blast disease in the Southern UNITED STATES in addition to Pi-ta . This study demonstrates that continued AVR gene monitoring in the pathogen population is critical for ensuring the effectiveness of deployed blast R genes in commercial rice fields.

Background: Trypanosoma cruzi, the etiologic agent of Chagas disease, is currently divided into six discrete typing units (DTUs), named TcI-TcVI. TcII is among the major DTUs enrolled in human infections in South America southern cone, where it is associated with severe cardiac and digestive symptoms. Despite the importance of TcII in Chagas disease epidemiology and pathology, so far, no genome-wide comparisons of the mitochondrial and nuclear genomes of TcII field isolates have been performed to track the variability and evolution of this DTU in endemic regions., Results: In the present work, we have sequenced and compared the whole nuclear and mitochondrial genomes of seven TcII strains isolated from chagasic patients from the central and northeastern regions of Minas Gerais, Brazil, revealing an extensive genetic variability within this DTU. A comparison of the phylogeny based on the nuclear or mitochondrial genomes revealed that the majority of branches were shared by both sequences. The subtle divergences in the branches are probably consequence of mitochondrial introgression events between TcII strains. Two T. cruzi strains isolated from patients living in the central region of Minas Gerais, S15 and S162a, were clustered in the nuclear and mitochondrial phylogeny analysis. These two strains were isolated from the other five by the Espinhaço Mountains, a geographic barrier that could have restricted the traffic of insect vectors during T. cruzi evolution in the Minas Gerais state. Finally, the presence of aneuploidies was evaluated, revealing that all seven TcII strains have a different pattern of chromosomal duplication/loss., Conclusions: Analysis of genomic variability and aneuploidies suggests that there is significant genomic variability within Minas Gerais TcII strains, which could be exploited by the parasite to allow rapid selection of favorable phenotypes. Also, the aneuploidy patterns vary among T. cruzi strains and does not correlate with the nuclear phylogeny, suggesting that chromosomal duplication/loss are recent and frequent events in the parasite evolution.

ESAT-6, CFP-10 and EspC are virulence factors that have been extensively assayed for bovine and human tuberculosis diagnosis due their potent T-cell inducing activities. While polymorphisms of ESAT-6 and CFP-10 were analyzed, with the description of CFP-10 variants in M. tuberculosis, this fact has not been explored in M. bovis field isolates. The coding sequences of esxA (ESAT-6), esxB (CFP-10) and mb3645c (EspC) from 58 M. bovis strains exhibiting genomic variability (spoligotyping) were analyzed. Two genes -esxA and esxB - remained invariant while mb3645c exhibited one synonymous polymorphism (G to A mutation, position 66bp) in one isolate, compared to M. bovis AF2122/97 reference strain. All isolates exhibited a synonymous nucleotide polymorphism simultaneously (G to A mutation, position 255bp), compared to M. tuberculosis H37Rv reference strain. This study confirms the high conservation for ESAT-6, CFP-10 and EspC in local M. bovis field isolates and reinforce the use of these three antigens in the diagnosis of bovine tuberculosis. Further studies should be performed to globally confirm these findings., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The objective of this study was to characterize the infectious bursal disease viruses (IBDVs) circulating in broiler chicken farms in China between 2012 and 2013. The VP2 gene sequences of nine newly isolated IBDVs, obtained using reverse transcriptase polymerase chain reaction, were determined and compared with worldwide reference isolates, which have been previously well characterized. Phylogenetic analysis revealed that the nine broiler IBDV isolates are closely related to very virulent IBDV (vvIBDV) strains. Analysis of the predicted amino acid sequences of VP2 from the nine vvIBDVs isolated from the broilers revealed that they share 99.2 to 100% sequence similarity. Additionally, amino acids A222, I242, I256, I294 and S299 of VP2 that are conserved among previously characterized vvIBDV strains are also encoded by the nine isolates. This study confirms the circulation of vvIBDVs in Chinese broiler chicken farms experienced slow evolution and was relatively stable in China., (Copyright © 2014 Elsevier B.V. All rights reserved.)