Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread worldwide since its emergence and is causing the disease COVID-19. According to WHO, this is a zoonotic disease. Several cases have already been discovered where companion animals were affected due to virus spillover from humans, however, the symptoms are mild in most cases. We report the first documented case of SARS-CoV-2 infection and death of a domestic cat (Felis silvestris catus) in Hungary, where no other disease could be detected.

Porcine parvovirus 8 (PPV8), a novel virus in the Parvoviridae family, was first identified in 2022 in lung samples of domestic pigs from China. Retrospective analyses showed that it had been circulating in China since 1998, but no other countries had reported its presence so far. A recent study conducted in South America did not detect any PPV8-positive samples in that region. Here we report the detection of PPV8 in Hungarian and Slovakian pig farms and the estimated prevalence of the virus in Hungary. Altogether 2230 serum, 233 oral fluid, and 115 processing fluid samples were systematically collected from 23 Hungarian and 2 Slovakian pig farms between 2020 and 2023. A real-time quantitative PCR method was developed to detect the viral genome. Our results revealed the presence of PPV8 on 65% of the Hungarian farms and on both Slovakian farms included in our study, marking its first detection in Europe. Oral fluid samples showed the highest positivity rates, reaching up to 100% in some herds. The viral genome was successfully detected in serum and processing fluid samples too, but with significantly lower prevalence rates of 4% and 5%, respectively. Genetic analysis of 11 partial VP2 sequences demonstrated high similarity to the original Chinese strain but with unique amino acid mutations, suggesting possible local evolution of the virus. Our study presents the first scientific evidence of PPV8 infection outside of China and offers a comprehensive assessment of its prevalence in the Hungarian pig population. Further research is required to understand its potential impact on swine health.

Background/Objectives: The ongoing COVID-19 pandemic has underscored the need for alternative prophylactic measures, particularly for populations where vaccines may not be effective or accessible. This study aims to evaluate the efficacy of intranasally administered IgY antibodies derived from hen egg yolks as a protective agent against SARS-CoV-2 infection in Syrian golden hamsters, a well-established animal model for COVID-19. Methods: Hens were immunized with the spike protein of SARS-CoV-2 to generate IgY antibodies. These antibodies were extracted from the egg yolks, purified, and their neutralizing activity was tested in vitro. Syrian golden hamsters were then treated with the IgY antibodies before being challenged with SARS-CoV-2. Viral loads were quantified using droplet digital PCR (ddPCR), and lung pathology was assessed through histopathological analysis. Results: The in vitro assays showed that IgY effectively neutralized SARS-CoV-2. In the in vivo hamster model, IgY treatment led to a significant reduction in viral loads and a marked decrease in lung consolidation and inflammation compared to the positive control group. Histopathological findings further supported the protective role of IgY in reducing lung damage caused by SARS-CoV-2. Conclusions: The results demonstrate that IgY antibodies exhibit strong antiviral activity and can significantly reduce SARS-CoV-2 viral loads and associated lung pathology in hamsters. These findings suggest that IgY could be a viable prophylactic option for preventing SARS-CoV-2 infection, particularly for individuals who cannot receive or respond to vaccines. Further studies are warranted to optimize dosage and explore the long-term efficacy of IgY antibodies.