Comparative Immunology Microbiology and Infectious Diseases最新文献

Background: African animal trypanosomosis (AAT) is one of the most serious diseases with ongoing detrimental effects on animal health and food production.

Methods: A cross-sectional study was conducted in the Bedele and Dedesa districts of Buno Bedele Zone, Southwest Ethiopia, to determine the prevalence of trypanosomosis and its vector distributions in small ruminants. Blood samples collected from a total of 384 small ruminants were examined for trypanosomosis via hematological analysis. For the tsetse distribution survey, 72 traps were deployed in the designated districts.

Results: Among the small ruminants examined with hematological techniques (n = 384), 16 (8 sheep and 8 goats) were infected with trypanosomes. The overall prevalence of trypanosomosis was 4.17 %. Only two species of trypanosomes, namely, T. vivax and T. congolense, were observed in this study, with equal prevalence rates (2.08 %). The mean PCV ± SD of the parasitemic small ruminants (24.37 ± 5.66) was significantly lower than that of the aparasitemic (27.48 ± 4.38) small ruminants. A total of 369 flies were caught (Glossina tachinoides (74.5 %) and G. morsitans (25.5 %)), with an overall mean apparent density of 2.56 flies per trap per day.

Conclusions: Overall, these results indicate that this disease is prevalent in these animals, and maintaining their health may play a significant role in defending the disease's spread. Greater emphasis needs to be given to controlling this disease in these ruminants, and the role of these animals as carriers of the disease needs to be considered in future planning and strategies of African animal trypanosomosis control activities.

Canine African trypanosomosis is endemic in sub-Saharan Africa. Chemotherapy remains the commonly employed approach to trypanosomosis control. However, it is beleaguered by the absence of new drugs, treatment failures, relapse infection and resistance. The efficacy of a high dose of isometamidium chloride (ISM) in single and mixed infections of T. congolense and T. brucei brucei therapy was assessed in dogs. Fifteen dogs employed in this study were allocated into four groups at random, each with four dogs except group I which had three dogs. Group I dogs were not infected while groups II and III dogs received 10⁶T. congolense and T. brucei brucei respectively. Group IV dogs received both (5 × 10⁵) T. congolense and T. brucei brucei. Groups II-IV dogs were dosed with 1 mg/kg ISM (Trypamidium-Samorin®) intraperitoneally on day 14 post-infection (PI). Parasitaemia levels, live body weight changes (LBWC), clinical signs, rectal temperature (RT), some haematological and serum biochemical parameters were used to evaluate the efficacy of high dose of ISM. Following infection, all the infected dogs became parasitaemic by the 14th day PI, with obvious clinical signs. Treatment with ISM cleared parasitaemia within 72 hours post-treatment, caused the reversal of the clinical signs, and enhanced the RT, LBWC, haematological and serum biochemical parameters of the dogs. Relapse infection was not recorded throughout the study duration (84 days post-infection). In conclusion, 1 mg/kg of ISM is effective in treating African trypanosomosis in dogs and should be adopted as a first-line treatment for the disease.

Animal trade has become a serious criminal practice in the world. Every day thousands of exotic wild animals, including reptiles, are farmed and sold worldwide. The illegal collection of turtles and tortoises remains completely unsupervised and represents a big challenge for responsible authorities. This has consequences for animals and public health because it can contribute to the spread of multiple zoonotic pathogens by introducing exotic species into new geographical areas like wet markets, pet shops, and houses. Non-typhoidal Salmonella are bacteria that can commonly cause self-limiting gastroenteritis but can also cause more serious symptoms, especially in more vulnerable people with impaired immune systems. There is growing evidence linking Salmonella to reptiles, especially chelonians, and its prevalence has increased recently as turtles and tortoises have become popular as new pets. These animals can potentially transmit antimicrobial resistant strains of Salmonella to humans, which puts people in danger, especially young children. Pet owners should be aware and take all the control measures to prevent the infection. This updated review investigates the reptile trade situations worldwide, including chelonians, explaining their relationship with the spread of Salmonella and the risk of infections for humans.

Canine distemper virus (CDV) causes a highly contagious and lethal disease in a vast range of carnivorous and non-carnivorous species. The study aimed to genetically investigate the hemagglutinin (H) gene and Fsp-coding region of CDV isolates from vaccinated dogs. Phylogenetic analysis of the H gene and Fsp-coding region showed that our viruses belonged to the Arctic-like lineage which was distinct from two commonly used vaccine strains (America-1 lineage strains) in Iran. Our data presented a high similarity between the H gene sequences of studied viruses. The multiple sequence alignment of the H gene of our viruses against vaccine strains revealed 91.3-95.6 % and 89.9-94.4 % in the level of nucleotide and amino acid identity, respectively. Our finding identified a potential recombination breakpoint occurring between codons 520-607, along with three positive selection sites including residues 415,547, and 549 among the H gene using the Data Monkey platform. A significant variation of B cell epitopes was found in Hemagglutinating and noose epitope (HNE), with respect to America-1 vaccine strains. Moreover, the H genes of studied viruses had 8 N-glycosylation sites, which is more than the America-1 vaccine strains. Our results confirmed that the circulation of Arctic-like lineage may be a prevalent lineage. Despite widespread vaccination, it does not provide full protection against CDV infection. Due to antigenic differences between our viruses and commonly used vaccine strains, it seems a novel vaccine strain is needed to prevent and prepare full protection against Arctic-like CDV infection.

Leptospirosis is a zoonosis with a worldwide distribution, which is transmitted through direct contact with infected animals or by contact with contaminated water or soil. Objectives was to examine the presence of antibodies against 23 serogroups of Leptospira in Lagostomus maximus and Chaetopractus villosus in La Pampa province, Argentina. Ninety-four serum samples from L. maximus (80) and C. villosus (14) were taken. The samples were analysed by microscopic agglutination test (MAT). Only 5/94 (5.3 %) serum samples presented antibodies against Leptospira sp. Three (21.4 %) serum samples from C. villosus, were reactive to the serogroups, Ballum, Grippotyphosa, Canicola and Celledoni, and two samples (2.5 %) of L. maximus to Pomona, Canicola and Ballum. This constitutes the first record of the presence of antibodies serogroup Celledoni in C. villosus and serogroups Pomona, Canicola and Ballum in L. maximus in Argentina.

Staphylococcus pseudintermedius is considered as a most common cause of canine pyoderma. Antimicrobial resistance is considered as a global public health concern. The main aim of the study was to evaluate the distribution of Antimicrobial resistance genes in S. pseudintermedius isolates using whole genome sequencing. In the current work, Antimicrobial susceptibility testing and Whole genome sequencing was performed on Five S. pseudintermedius isolates recovered from canine pyoderma cases presented at Veterinary Clinical Complex, Navsari. Bioinformatics analysis of sequencing data was performed to detect Antimicrobial resistance genes, plasmids and mobile genetic elements in S. pseudintermedius isolates. All S. pseudintermedius isolates shows resistance towards amikacin, ampicillin, cefpodoxime, cephalexin, erythromycin and trimethoprim. Higher sensitivity was observed against clindamycin (4/5, 80 %). A total 15 AMR genes, one plasmid (repUS43), two insertion sequences (ISLgar5 and IS256) and one Integrative Conjugative Element (Tn6009) were detected using whole genome sequencing analysis. This study aids us to know about relationship between antimicrobial resistance and presence of AMR genes, plasmids and mobile genetic elements.

Feline immunodeficiency virus (FIV) is a retrovirus affecting domestic cats worldwide and causing immunosuppression and reduced quality of life. The prevalence of FIV infection varies according to geographic regions / countries and it is associated with domestic cat health managements (vaccination, neutering, basic health care, etc.). This study aimed to evaluate prevalence, risk factors and some clinical information of FIV infection in a domestic cat population in southern Brazil. A total of 366 cats from ten different veterinary facilities and 43 neighborhoods located in the city of Caxias do Sul were sampled for this study. Each animal was examined by a clinical veterinarian and blood was collected for laboratory analysis. Blood samples were tested with a point-of-care (POC) assay to detect FIV antibodies and a real-time polymerase chain reaction (qPCR) to detect and quantify FIV proviral DNA. The results demonstrated an overall prevalence of 7.1 % (n = 26; 95 % CI = 4.9 % - 10.2 %) of FIV infection. FIV-positive cats demonstrated undetectable (n = 6; 23.1 %) and detectable (n = 20; 76.9 %) proviral DNA, with loads varying from less than 10 (10¹) to 4460,000 (10^6.6) with a mean of 480,000 (10^5.7) copies/mL. FIV-positive cats were significantly older (median age of 7 years), also presenting outdoor access (OR: 5.0, p = 0.046), feline leukemia virus (FeLV) coinfection (OR: 7.1, p < 0.001) and other chronic diseases (OR: 4.1, p = 0.34) as main risk factors. FIV-positive animals presented a 9.9- and 7.6-times higher risk for developing lymphoma and anemia in the multivariate analysis. This study contributes to assess some important epidemiological aspects of FIV infection in cats in southern Brazil, highlighting the strong association of FIV and FeLV coinfection.

Leptospirosis is a zoonotic disease caused by the bacteria of the genus Leptospira, which is responsible for substantial impacts on the economy, animal health, and public health. This disease has a global distribution and is particularly prevalent in Brazil. While leptospirosis can affect different animal species, including domestic ones such as dogs and cats, the role of dogs in its epidemiology is established and well-understood. Conversely, the role of domestic cats in the epidemiology of leptospirosis remains unclear, with a significant lack of studies elucidating the roles they play in the transmission of Leptospira spp. and the bacterial species they can host. Therefore, this study aimed to evaluate the presence of Leptospira spp. DNA in domestic cats and to assess the phylogenetic relationships of the identified microorganisms in the Central region of Rio Grande do Sul State (RS) in southern Brazil. The samples were evaluated for the presence of the gene lipL32 by polymerase chain reaction and sequencing of the amplified fragment, followed by phylogenetic analysis. DNA from Leptospira spp. was extracted from the kidney tissue of domestic cats. Pathogenic Leptospira spp. DNA was detected in 22.1 % (67/303) of the samples. Molecular analyses revealed the presence of L. borgpetersenii and L. interrogans in these animals. This study is the first to identify L. borgpetersenii and L. interrogans in domestic cats in RS, highlighting their potential role as bacterial reservoirs. Our findings provide valuable insights into the epidemiology of leptospirosis and can contribute to sanitary measures aimed at controlling and preventing the disease, ultimately protecting public health.

Reticuloendotheliosis virus (REV) is a retrovirus in poultry that can atrophy immune organs and cause immunosuppression and tumor diseases. Our previous results revealed that, in the spleen of SPF chickens infected with REV-SNV, gga-miR-222b-5p expression was upregulated at 7, 14 and 21 dpi, and MAPK10 expression was downregulated, both of which were negatively correlated, with a targeted relationship between the two at 28, 35 and 42 dpi. To understand and analyze the expression patterns of MAPK10 and gga-miR-222b-5p in infected chickens at different times and in different immune organs, qRT-PCR was used to analyze the spleen, bursa of Fabricius and thymus samples of SPF chickens at 7, 14, 21, 28, 35 and 42 dpi. The results revealed that, in the spleen, MAPK10 gene expression was highly significantly downregulated at 7, 14, 21, 35 and 42 dpi, and gga-miR-222b-5p expression was significantly upregulated at six-time points. In the bursa of Fabricius, MAPK10 expression was significantly downregulated at six-time points, and gga-miR-222b-5p expression was upregulated at 7, 21, 28, 35 and 42 dpi. In the thymus, MAPK10 and gga-miR-222b-5p expression was upregulated at six-time points. A negative regulatory relationship was evident in the spleen and bursa of Fabricius but not in the thymus. This study suggested that gga-miR-222b-5p may induce the downregulation of MAPK10 in the spleen and bursa of Fabricius and promote tumor formation.

Evidence of SARS-CoV-2 infections in different animal species raises concerns about the potential for animal reservoirs and transmission to humans. Here, we evaluate the exposure of exotic pet species to this virus throughout the early years of the pandemic (2020 - 2022) in southern Spain. A total of 180 exotic pets (126 domestic rabbits, 31 ferrets, and 23 rodents) were analyzed for antibodies against SARS-CoV-2 using two different ELISAs. ELISA-positive sera were subsequently tested for specific neutralizing antibodies (nAbs) using the virus neutralization test (VNT). Only one brown rat (Rattus norvegicus), representing 0.6 % of the total, tested positive by ELISA, yet showed negative result for SARS-CoV-2 nAbs by VNT. Our results suggest a very limited risk of SARS-CoV-2 transmission among humans and sympatric exotic pet species in the study region. However, the virus's potential for interspecies transmission emphasizes the need for ongoing surveillance, especially in settings with frequent human-animal interactions, to avoid potential virus evolution, the emergence of new animal reservoirs, and spillover events.