A cross-sectional retrospective study of SARS-CoV-2 seroprevalence in domestic cats, dogs and rabbits in Poland.

BACKGROUND: Coronaviruses (CoVs) have long been known to cause infection in domestic and free-living birds and mammals including humans. The zoonotic origin of SARS-CoV-2 and the biological properties of CoVs, including ability to cross interspecies barriers, enable its emergence in populations of various animals, including companion animals (cats, dogs, rabbits) an area requiring further study. To date, several cases of cats and dogs positive for SARS-CoV-2 and/or specific antibodies have been described. The aim of our cross-sectional retrospective study is to determine seroprevalence of SARS-CoV-2 in domestic dog, cat and rabbit population during recent COVID-19 pandemic in Poland. RESULTS: In total, serum samples from 279 cats and 343 dogs and 29 rabbits were used in the study. The seroprevalence of SARS-CoV-2 in cats and dogs reached 1.79% (95% CI: 0.77 - 4.13) and 1.17% (95% CI 0.45 - 2.96), respectively (p ≥ 0.05). Anti- SARS-CoV-2 antibodies were detected in 5 cats (mean S/P% 106 ± 48.23) and 4 dogs (mean S/P% 78.5 ± 16.58). All 29 samples from rabbits were negative for SARS-CoV-2 antibodies. No significant gender or age differences in seroprevalence in dogs and cats (p ≥ 0.05) were found. None of the animals with anti-SARS-CoV-2 antibodies displayed respiratory or gastrointestinal signs at the time of sampling. CONCLUSIONS: Our results confirmed previous findings that SARS-CoV-2 infections in companion animals occurs but are not frequent. Future serological testing of large pet population may provide a comprehensive picture of disease dynamics in companion animals.

African Swine Fever Virus as a Difficult Opponent in the Fight for a Vaccine-Current Data.

Prevention and control of African swine fever virus (ASFV) in Europe, Asia, and Africa seem to be extremely difficult in view of the ease with which it spreads, its high resistance to environmental conditions, and the many obstacles related to the introduction of effective specific immunoprophylaxis. Biological properties of ASFV indicate that the African swine fever (ASF) pandemic will continue to develop and that only the implementation of an effective and safe vaccine will ensure a reduction in the spread of ASFV. At present, vaccines against ASF are not available. The latest approaches to the ASFV vaccine's design concentrate on the development of either modified live vaccines by targeted gene deletion from different isolates or subunit vaccines. The construction of an effective vaccine is hindered by the complex structure of the virus, the lack of an effective continuous cell line for the isolation and propagation of ASFV, unpredictable and stain-specific phenotypes after the genetic modification of ASFV, a risk of reversion to virulence, and our current inability to differentiate infected animals from vaccinated ones. Moreover, the design of vaccines intended for wild boars and oral administration is desirable. Despite several obstacles, the design of a safe and effective vaccine against ASFV seems to be achievable.

Distribution of Trichinella spiralis, Trichinella britovi, and Trichinella pseudospiralis in the Diaphragms and T. spiralis and T. britovi in the Tongues of Experimentally Infected Pigs.

There is little or even no data in the global literature on the distribution of different species of Trichinella in the individual parts of the diaphragms and tongues in infected pigs. This is of particular importance from the food safety point of view and for the conduct of routine testing of pig carcasses for Trichinella as well as epidemiological surveys. Therefore, the aim of the present study was to evaluate the distribution of Trichinella spiralis (T. spiralis), Trichinella britovi (T. britovi), and Trichinella pseudospiralis (T. pseudospiralis) ML in various parts of the diaphragm (the pillars, costal, and sternal part) and the distribution of encapsulated species of Trichinella (T. spiralis and T. britovi) in various parts of the tongues (the tip, body, and root) of experimentally infected pigs. The diaphragm pillars were the most heavily parasitized part of the diaphragm both in groups of pigs infected with particular species of Trichinella and in groups of pigs presenting different levels of infection; however, statistical differences were observed only in the group of pigs with moderate (21-35 larvae per gram-lpg) or moderately high (35-55 lpg) intensity of Trichinella spp. infection in the entire diaphragm. In all groups of pigs, regardless of the infecting Trichinella species or infection level, larvae showed a homogeneous distribution on both sides of the diaphragm and excluding those of T. pseudospiralis, also in all three parts of the tongue. Histological examination showed features of a differential inflammatory response around larvae of the different Trichinella species. This study confirmed that for mandatory examination of pig carcasses using a pooled-sample digestion assay in which each pig is intended to be represented by a 1 gram sample taken from the diaphragm pillars, if that tissue is not available, the mass of the sample taken from the remaining diaphragm parts (costal or sternal) should be at least double that from the pillars. Histological findings confirmed that the inflammatory pattern of pig muscles varies depending on the Trichinella species triggering the infection and is less intense in the case of infections with T. pseudospiralis than in infections with encapsulated species of Trichinella (T. spiralis and T. britovi).