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Zoonotic origins and animal hosts of coronaviruses causing human disease pandemics: A review
2020
Abdalla A. Latif | Samson Mukaratirwa
The first known severe disease caused by a coronavirus (CoV) in humans emerged with the severe acute respiratory syndrome (SARS) epidemic in China, which killed 774 people during its 2002/2003 outbreak. The Middle East respiratory syndrome (MERS) was the second human fatal disease, which started in 2012 in Saudi Arabia and resulted in 858 fatalities. In December 2019, a new virus, SARS-CoV-2 (COVID-19), originating from China, began generating headlines worldwide because of the unprecedented speed of its transmission; 5.2 million people were infected and 338 480 had been reported dead from December 2019 to May 2020. These human coronaviruses are believed to have an animal origin and had reached humans through species jump. Coronaviruses are well known for their high frequency of recombination and high mutation rates, allowing them to adapt to new hosts and ecological niches. This review summarises existing information on what is currently known on the role of wild and domesticated animals and discussions on whether they are the natural reservoir/amplifiers hosts or incidental hosts of CoVs. Results of experimental infection and transmission using different wild, domesticated and pet animals are also reviewed. The need for a One Health approach in implementing measures and practices is highlighted to improve human health and reduce the emergence of pandemics from these zoonotic viruses.
Mostrar más [+] Menos [-]E-test determination of antifungal susceptibility of Candida species isolated from turkeys
2020
Sokół, Ireneusz | Tokarzewski, Stanisław | Bobrek, Kamila | Gaweł, Andrzej
Candida species are a natural component of the intestinal tract microflora, but in favourable conditions they can cause superficial, mucosal, or even systemic candidiasis. Poultry production might be a source of human drug-resistant yeast infections, including Candida spp. The limited data concerning the antifungal susceptibility of poultry Candida isolates prompted us to carry out research to determine the susceptibility of isolates from turkey intestinal tracts. The beak cavity, crop and cloaca were swabbed of 580 turkeys from 58 flocks in western Poland. The susceptibility tests were conducted using the E-test method with amphotericin B, fluconazole, itraconazole, and voriconazole on 52 isolates of C. albicans, C. catenulata, C. glabrata, C. palmioleophila, C. rugosa, C. krusei and C. lusitaniae. All isolates were susceptible to voriconazole. According to the MIC values obtained for amphotericin B and fluconazole, all Candida spp. isolates were classified as susceptible according to the described breakpoints except for C. krusei, which was the only isolate that was amphotericin B-, fluconazole- and itraconazole-resistant. The susceptibility to itraconazole varied: 11 of the Candida isolates were susceptible (21.1%), 29 were dose-dependently susceptible (55.8%), and 12 isolates were resistant (23.1%). There are few resistant strains of Candida in turkeys, and the drug resistance varies. When Candida passes from turkeys to humans, there is a wide range of antifungal treatment options.
Mostrar más [+] Menos [-]Animal coronaviruses in the light of COVID-19
2020
Domańska-Blicharz, Katarzyna | Woźniakowski, Grzegorz | Konopka, Bogdan | Niemczuk, Krzysztof | Welz, Mirosław | Rola, Jerzy | Socha, Wojciech | Orłowska, Anna | Antas, Marta | Śmietanka, Krzysztof | Cuvelier-Mizak, Beata
Coronaviruses are extremely susceptible to genetic changes due to the characteristic features of the genome structure, life cycle and environmental pressure. Their remarkable variability means that they can infect many different species of animals and cause different disease symptoms. Moreover, in some situations, coronaviruses might be transmitted across species. Although they are commonly found in farm, companion and wild animals, causing clinical and sometimes serious signs resulting in significant economic losses, not all of them have been classified by the World Organization for Animal Health (OIE) as hazardous and included on the list of notifiable diseases. Currently, only three diseases caused by coronaviruses are on the OIE list of notifiable terrestrial and aquatic animal diseases. However, none of these three entails any administrative measures. The emergence of the SARS-CoV-2 infections that have caused the COVID-19 pandemic in humans has proved that the occurrence and variability of coronaviruses is highly underestimated in the animal reservoir and reminded us of the critical importance of the One Health approach. Therefore, domestic and wild animals should be intensively monitored, both to broaden our knowledge of the viruses circulating among them and to understand the mechanisms of the emergence of viruses of relevance to animal and human health.
Mostrar más [+] Menos [-]Histamine and other biogenic amines in food
2020
Durak-Dados, Agata | Michalski, Mirosław | Osek, Jacek
The aim of this paper is to give an overview of the presence of biogenic amines, particularly histamine, in various food products, discuss the most important factors influencing their accumulation, and address potential toxicity and safe limits in food. Biogenic amines are natural components of animal and plant raw materials, where they are present at concentrations appearing non-harmful to human health. Their increased content in foods results from the activity of endogenous enzymes or from the microbial decarboxylation of amino acids during controlled or spontaneous fermentation, processing, storage, and distribution. General knowledge of biogenic amines, factors favouring their formation and their safe limits in food are useful in preventing exposure to their toxic effects on the human body. Based on this information, appropriate prophylaxis can be applied, which will consist primarily of maintenance of good hygiene standards of raw materials and products, employment of appropriate processing procedures and upkeep of sanitary food storage conditions.
Mostrar más [+] Menos [-]Staphylococcus spp. from wild mammals in Aragón (Spain): antibiotic resistance status
2020
García, Leticia Alcalá | Torres, Carmen | López, Antonio Rezusta | Rodríguez, Carmelo Ortega | Espinosa, Jesús Orós | Valencia, Carmen Simón
Antimicrobial resistance is a global health threat. It has been studied in humans and domestic animals, but there is a lack of data on wild animals. The objective of this study is the elucidation of its patterns in Staphylococcus spp. isolated from wild mammals of the Autonomous Community of Aragón (Spain). A total of 103 mammals (Artiodactyla, Carnivora, Chiroptera, Erinaceomorpha, and Lagomorpha) were studied. A recovery centre provided 32 and hunting 71. Nasal and faecal samples yielded 111 staphylococci, which were identified by matrix-assisted laser desorption/ionization–time of flight mass spectrometry. A susceptibility test to 11 antibiotics was carried out, and statistical analysis was performed. Some differences were detected in bacterial prevalence depending on how the mammal fed. Artiodactyla, mainly hunted, were predisposed to carry coagulase-positive staphylococci. The staphylococci species recovered were resistant to at least two classes of antibiotics, and were disseminated in all of the geographical areas studied. Resistant staphylococci are widely distributed in the wild mammals in the areas of the study, but the resistance quantified in them is lower than that to be expected if the use of antibiotics in farms had a direct influence on the wildlife and its environment. On the other hand, resistance to antibiotics restricted to human use was widely disseminated in various wild animal species.
Mostrar más [+] Menos [-]The influence of high and low doses of acrylamide on porcine erythropoiesis
2020
Snarska, Anna | Palus, Katarzyna | Wysocka, Dominika | Rytel, Liliana
Due to the widespread occurrence of acrylamide in the environment, its likely carcinogen status, and the suitability of the pig model as a human analogue, the authors decided to evaluate the impact of high and low doses of this compound on the processes of erythropoiesis in swine bone marrow. The experiment was carried out on Danish Landrace pigs at the age of eight weeks and body weight about 20 kg. The animals were divided into three equal groups consisting of five pigs in each. Control animals received empty gelatin capsules (placebos). Animals from the first experimental group received a low dose of acrylamide of 0.5 μg/kg b.w./day (> 99% purity; Sigma-Aldrich, Poland), and animals from the second experimental group received a dose 10 times higher. Placebos and acrylamide capsules were administered with feed every morning for 28 days. After anaesthetisation of the animals, bone marrow from the femur was collected into tubes without an anticoagulant on days 0 and 28. After drying and staining, bone marrow smears were subjected to detailed cytological evaluation using a light microscope. This study showed that high and low doses of acrylamide affected the process of porcine erythropoiesis. The cytotoxic effect of acrylamide on this process was demonstrated in a change of the polychromatic erythroblasts/normochromatic erythroblasts ratio. Both doses of acrylamide caused a decrease in the number of ortho- and polychromatic erythroblasts.
Mostrar más [+] Menos [-]Highly pathogenic avian influenza H5N8 in Poland in 2019–2020
2020
Śmietanka, Krzysztof | Świętoń, Edyta | Kozak, Edyta | Wyrostek, Krzysztof | Tarasiuk, Karolina | Tomczyk, Grzegorz | Konopka, Bogdan | Welz, Mirosław | Domańska-Blicharz, Katarzyna | Niemczuk, Krzysztof
Repeated incursions of highly pathogenic avian influenza virus (HPAIV) H5 subtype of Gs/GD lineage pose a serious threat to poultry worldwide. We provide a detailed analysis of the spatio-temporal spread and genetic characteristics of HPAIV Gs/GD H5N8 from the 2019/20 epidemic in Poland. Samples from poultry and free-living birds were tested by real-time RT-PCR. Whole genome sequences from 24 (out of 35) outbreaks were generated and genetic relatedness was established. The clinical status of birds and possible pathways of spread were analysed based on the information provided by veterinary inspections combined with the results of phylogenetic studies. Between 31 December 2019 and 31 March 2020, 35 outbreaks in commercial and backyard poultry holdings and 1 case in a wild bird were confirmed in nine provinces of Poland. Most of the outbreaks were detected in meat turkeys and ducks. All characterised viruses were closely related and belonged to a previously unrecognised genotype of HPAIV H5N8 clade 2.3.4.4b. Wild birds and human activity were identified as the major modes of HPAIV spread. The unprecedentedly late introduction of the HPAI virus urges for re-evaluation of current risk assessments. Continuous vigilance, strengthening biosecurity and intensifying surveillance in wild birds are needed to better manage the risk of HPAI occurrence in the future.
Mostrar más [+] Menos [-]Prevalence and drug resistance of Salmonella in dogs and cats in Xuzhou, China
2020
Wei, Lingling | Yang, Cheng | Shao, Wangfeng | Sun, Tongzheng | Wang, Jianyu | Zhou, Zhengkun | Chen, Caifa | Zhu, Aihua | Pan, Zhiming
Salmonellosis is a zoonotic disease, and Salmonella spp. can sometimes be found in dogs and cats, posing a risk to human health. In this study, the prevalence and antimicrobial susceptibility of faecal Salmonella were investigated in pet dogs and cats in Xuzhou, Jiangsu Province, China. Faecal samples from 243 dogs and 113 cats, at seven pet clinics, were tested between March 2018 and May 2019. Each Salmonella isolate was characterised using serotyping and antimicrobial susceptibility tests. The prevalence of Salmonella was 9.47% in dogs and 1.77% in cats. Among the 25 isolates, eight serotypes of Salmonella enterica subsp. enterica were detected, S. Kentucky (n = 11), S. Indiana (n = 5), and S. Typhimurium (n = 4) predominating. S. Derby, S. Toucra, S. Sandiego, S. Newport, and S. Saintpaul all occurred singly. The 23 Salmonella strains found in dogs were from seven different serovars, while the two strains in cats were from two. The highest resistance rates were found for tetracycline (92%), azithromycin (88%), cefazolin (84%), nalidixic acid (80%), ampicillin (80%), ceftriaxone (80%), and streptomycin (76%). Resistance to three or more antimicrobial agents was detected in 24 (96%) isolates. Most of the S. Kentucky and S. Indiana isolates were multi-drug resistant to more than 11 agents. The carriage rate was far higher in dogs than in cats from Xuzhou. Some isolated strains were highly resistant to antimicrobials used to treat infections in humans and pets, which may raise the risk of humans being infected with multi-drug resistant Salmonella via close contact with pets.
Mostrar más [+] Menos [-]In-vitro effects of taurolidine alone and in combination with mitoxantrone and/or piroxicam on canine transitional cell carcinoma
2020
Byer, Brittney | Schlein, Lisa J. | Rose, Barbara | Seguin, B. (Bernard)
The objective of this in-vitro study was to evaluate taurolidine as a therapy for transitional cell carcinomas in canine patients. Transitional cell carcinoma (TCC) is the most common cancer of the urinary bladder in dogs and accounts for approximately 2% of reported malignancies in this species. There is no cure for this neoplasm and most dogs are lost from complications associated with progression of the local disease. Taurolidine has been shown to have anti-tumor and antiangiogenic effects against a variety of neoplasms in human and animal models. Four canine TCC cell lines were treated with various concentrations of taurolidine, mitoxantrone, and piroxicam alone. In addition, combinations of taurolidine/mitoxantrone, taurolidine/piroxicam, mitoxantrone/piroxicam, and taurolidine/mitoxantrone/piroxicam were assessed. Susceptibility of the TCC cell lines was based on a 72-hour growth inhibition assay using resazurin with absorbance measured at 530/590. The ability of taurolidine to induce apoptosis was evaluated on 2 of the cell lines with an Annexin-V/propidium iodide assay. All cell lines were susceptible to treatment with taurolidine, mitoxantrone, and piroxicam alone. The results of the combination therapies of the 3 drugs were dependent on cell line and concentration and revealed no change in cell growth inhibition, a subadditive relationship, or a synergistic relationship. Taurolidine induced apoptosis in a concentration- and time-dependent fashion. Taurolidine alone showed significant effects on cell viability in vitro in canine TCC cell lines and these effects can be potentially enhanced with the addition of mitoxantrone and/or piroxicam.
Mostrar más [+] Menos [-]Effect of Achyranthes japonica Nakai extract on immunity and anti-inflammation in dogs
2020
Lee, Gun-Hwi | Hwang, Kyung-A | Kang, Ji-Houn | Choi, Kyung-Chul
Achyranthes japonica Nakai (A. japonica) is a medicinal herb found widely distributed throughout Korea. The biological activities of A. japonica are well-documented and include anti-fungal, anti-inflammatory, and immunity enhancement. The objective of the present study was to investigate the immune-related activities of A. japonica extract in dogs. The extract was acquired by ethanol extraction and purified by filtration. To examine the effect of A. japonica extract on immune cell viability, human lymphocytes, such as Jurkat T-cells and Ramos B-cells, were exposed to the extract. After treatment with the extract, the number of Ramos B-cells was increased, whereas Jurkat T-cells remained unaffected. Griess assay revealed decreased nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated mouse macrophage Raw 264.7 cells after exposure to A. japonica extract. To evaluate the in-vivo effect in dogs, feed containing A. japonica extract was provided to 8 dogs for 2 months. Blood samples were collected before, during, and after consumption of the feed. Peripheral blood mononuclear cells (PBMCs) were isolated from the blood samples and the number of T-cells and B-cells were assessed using flow cytometry with anti-dog fluorescein isothiocyanate (FITC)-conjugated CD3 and anti-dog phycoerythrin (PE)-conjugated CD21 antibodies, respectively. We observed a significant increase in the average number of B-cells in the PBMCs during ingestion of the feed containing A. japonica. In addition, enzyme-linked immunosorbent assay (ELISA) revealed a decrease in the levels of tumor necrosis factor-alpha (TNF-α), a pro-inflammatory cytokine, in 3 out of 8 dogs and increased levels of interleukin-10 (IL-10), an anti-inflammatory cytokine, in 4 out of 8 dogs. Taken together, we believe that these changes indicate that A. japonica extract is beneficial in improving the immunity of dogs by stimulating B-cells and inducing production of anti-inflammatory responses.
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