No abstract

Over a year into the COVID-19 pandemic, there is growing evidence that SARS-CoV-2 infections among dogs are more common than previously thought. In this study, the prevalence of SARS-CoV-2 antibodies was investigated in two dog populations. The first group was comprised of 1069 dogs admitted to the Veterinary Teaching Hospital for any given reason. The second group included dogs that shared households with confirmed COVID-19 cases in humans. This study group numbered 78 dogs. In COVID-19 infected households, 43.9% tested ELISA positive, and neutralising antibodies were detected in 25.64% of dogs. Those data are comparable with the secondary attack rate in the human population. With 14.69% of dogs in the general population testing ELISA positive, there was a surge of SARS-CoV-2 infections within the dog population amid the second wave of the pandemic. Noticeably seroprevalence of SARS-CoV-2 in the dog and the human population did not differ at the end of the study period. Male sex, breed and age were identified as significant risk factors. This study gives strong evidence that while acute dog infections are mostly asymptomatic, they can pose a significant risk to dog health. Due to the retrospective nature of this study, samples for viral isolation and PCR were unavailable. Still, seropositive dogs had a 1.97 times greater risk for developing central nervous symptoms.

Feline immunodeficiency virus (FIV) and feline leukaemia virus (FeLV) are among the most common infectious diseases of cats and have a global impact on the health of domestic cats. Both viruses belong to the Retroviridae family and like other members of this family they are associated with lifelong infection after integration of the proviral DNA into the host cell genome. Prevalence data are necessary to define the risk factors, and prophylactic, management, diagnostic and therapeutic measures for stray and owned sick cats. In this study 324 domestic cats were tested with commercially available assays. The tested cats were divided into two groups, stray and owned sick cats. The overall percentage of seropositives for FIV infection was 18.51% and the prevalence for FeLV infection was 14.50%. FIV prevalence ranged from 13.13% in stray cats up to 20.88% within the sick owned cat group. The prevalence for FeLV infection was 6.06% in stray cats and 18.22% among sick owned cats. Regarding FIV infection, our study confirmed a significantly higher percentage of seropositives for male cats, as well as for sexually intact ones within the sick owned group. Males were significantly more likely to have positive results for both retroviral infections. The study confirmed the high rate of retroviral infections in cats from the Zagreb urban area. Males, sexually intact ones, and territorial aggression are predisposing factors for FIV infection, but not for FeLV. Preventive measures should include identification and segregation of infected cats, castration of outdoor male cats, and vaccination.

This study was performed on 29 domestic cats with a variety of clinical signs, possibly related to FIV infection. Blood samples were tested by a rapid immunochromatographic (ICA) procedure for detection of FIV antibodies. Subsequently, polymerase chain reaction (PCR) was performed to amplify a portion of the proviral gag gene. All 11 positive PCR products were sequenced and compared with previously reported FIV sequences. Croatian proviral isolates that could be amplified were clustered within subtype B, and additional heterogeneity was confirmed by the formation of three separate clusters. Phylogenetic analysis of circulating strains in Croatia and in southeast Europe is necessary to improve diagnostic methods and selection of the appropriate vaccinal strains.

Clinical cases resembling strangles are regularly seen in some areas of Croatia. However, there are no data on the prevalence of infection and the clinical forms or geographic distribution of the disease. The aim of this study was to determine the seroprevalence of Streptococcus equi subspecies equi in horses resident in Croatia, in order to estimate the geographic distribution of infection. The study included 291 horse sera from the eight counties where the majority of Croatian horses are kept. Sera were tested by indirect ELISA (iELISA) for the presence of serum antibodies against S. equi protein A (SEQ_2190) and protein C (SeM). Positive horses were detected in all counties. Overall seroprevalence was 16.5 per cent (48/291), ranging from 7.1 to 29.6 per cent. A positive association was observed between the population size of the horses in the counties and the seropositivity rates: the larger the population, the higher the seropositivity. The results of this study suggest that S. equi infection is widespread in Croatia. Further investigation of the clinical manifestations, circulating strains and other characteristics of the disease in Croatia and raising awareness of the disease among horse owners are now required.