Seropositivity rates of zoonotic pathogens in small ruminants and associated public health risks at informal urban markets in Zambia.

Informal livestock markets are an important source of animal-derived proteins for growing urban populations in countries such as Zambia. In parallel, they can also constitute pathways of zoonotic pathogen transmission to humans. This risk is aggravated by limited disease monitoring and poor control systems with regards to biosecurity and public health. The aim of this study was to investigate the risks for spread of zoonotic diseases in Zambia's two largest informal small ruminant markets, located in Lusaka and Kasumbalesa, through combining seroepidemiology with interviews and observations. In April, May and September 2018, serum samples (n = 237) were collected and analysed for antibodies for the zoonotic pathogens Brucella spp., Coxiella (C.) burnetii and Rift Valley fever virus (RVFV), using commercially available enzyme linked immunosorbent assays (ELISA). In addition, slaughterhouse activities were observed and semi-structured interviews and focus group discussions held with slaughterhouse workers and small ruminant traders, focusing on the handling of animals and meat, and the perceptions of zoonotic disease risks at slaughter and consumption. The study found seropositivity rates of 10.1% (95% confidence interval [CI] 6.60-14.7) for Brucella spp., 5.9% (95% CI 3.27-9.71) for C. burnetii, and 0.8% (95% CI 0.10-3.01) for RVFV. Interviews with value chain members and observations at the slaughterhouse revealed unsanitary procedures and multiple occupational hazards for slaughterhouse workers. This study showed that the Zambian informal small ruminant trade system poses risks to public health, and that these risks are exacerbated by a lack of information about food-borne diseases and how associated risks can be mitigated amongst value chain actors. The results of this study can be used to formulate preventive measures to improve informal meat markets and reduce the risks to public health.

Evolutionary genetics of canine respiratory coronavirus and recent introduction into Swedish dogs.

Canine respiratory coronavirus (CRCoV) has been identified as a causative agent of canine infectious respiratory disease, an upper respiratory infection affecting dogs. The epidemiology is currently opaque, with an unclear understanding of global prevalence, pathology, and genetic characteristics. In this study, Swedish privately-owned dogs with characteristic signs of canine infectious respiratory disease (n = 88) were screened for CRCoV and 13 positive samples (14.7%, 8.4-23.7% [95% confidence interval (CI)]) were further sequenced. Sequenced Swedish CRCoV isolates were highly similar despite being detected in dogs living in geographically distant locations and sampled across 3 years (2013-2015). This is due to a single introduction into Swedish dogs in approximately 2010, as inferred by time structured phylogeny. Unlike other CRCoVs, there was no evidence of recombination in Swedish CRCoV viruses, further supporting a single introduction. Finally, there were low levels of polymorphisms, in the spike genes. Overall, we demonstrate that there is little diversity of CRCoV which is endemic in Swedish dogs.

Could Naturally Occurring Coronaviral Diseases in Animals Serve as Models for COVID-19? A Review Focusing on the Bovine Model.

The current pandemic of COVID-19 has highlighted the importance of basic studies on coronaviruses (CoVs) in general, and severe acute respiratory syndrome CoV type 2 (SARS-CoV-2) in particular. CoVs have for long been studied in veterinary medicine, due to their impact on animal health and welfare, production, and economy. Several animal models using coronaviral disease in the natural host have been suggested. In this review, different animal models are discussed, with the main focus on bovine CoV (BCoV). BCoV is endemic in the cattle population worldwide and has been known and studied for several decades. SARS-CoV-2 and BCoV are both betacoronaviruses, where BCoV is highly similar to human coronavirus (HCoV) OC43, encompassing the same virus species (Betacoronavirus 1). BCoV causes respiratory and gastrointestinal disease in young and adult cattle. This review summarizes the current knowledge of the similarities and dissimilarities between BCoV and SARS-CoV-2, as well as discussing the usage of BCoV as a model for human CoVs, including SARS-CoV-2.