Land application of manure that contains antibiotics and resistant bacteria may facilitate the establishment of an environmental reservoir of antibiotic-resistant microbes, promoting their dissemination into agricultural and natural habitats. The main objective of this study was to search for acquired antibiotic resistance determinants in the gut microbiota of wild boar populations living in natural habitats. Gastrointestinal samples of free-living wild boars were collected in the Zemplén Mountains in Hungary and were characterised by culture-based, metagenomic, and molecular microbiological methods. Bioinformatic analysis of the faecal microbiome of a hunted wild boar from Japan was used for comparative studies. Also, shotgun metagenomic sequencing data of two untreated sewage wastewater samples from North Pest (Hungary) from 2016 were analysed by bioinformatic methods. Minimum spanning tree diagrams for seven-gene MLST profiles of 104 E. coli strains isolated in Europe from wild boars and domestic pigs were generated in Enterobase. In the ileum of a diarrhoeic boar, a dominant E. coli O112ab:H2 strain with intermediate resistance to gentamicin, tobramycin, and amikacin was identified, displaying sequence type ST388 and harbouring the EAST1 toxin astA gene. Metagenomic analyses of the colon and rectum digesta revealed the presence of the tetQ, tetW, tetO, and mefA antibiotic resistance genes that were also detected in the gut microbiome of four other wild boars from the mountains. Furthermore, the tetQ and cfxA genes were identified in the faecal microbiome of a hunted wild boar from Japan. The gastrointestinal microbiota of the free-living wild boars examined in this study carried acquired antibiotic resistance determinants that are highly prevalent among domestic livestock populations.

African swine fever (ASF) is an acute viral haemorrhagic disease of pigs and wild boars. It presents a serious threat to pig production worldwide, and since 2007, ASF outbreaks have been recorded in the Caucasus, Eastern Europe, and the Baltic States. In 2014, the disease was detected in Poland. ASF is on the list of notifiable diseases of the World Organisation for Animal Health (OIE). Due to the lack of an available vaccine and treatment, the countermeasures against the disease consist in early detection of the virus in the pig population and control of its spread through the elimination of herds affected by disease outbreaks. Knowledge of the potential vectors of the virus and its persistence in the environment is crucial to prevent further disease spread and to understand the new epidemiology for how it compares to the previous experience in Spain gathered in the 1970s and 1980s.

Introduction: Aujeszky’s disease virus (ADV) infects a wide range of animals, including members of the Suidae family, i.e. domestic and wild pigs, as well as wild boar. Since wild boar are a potential ADV reservoir and a source of infection for domestic pigs, the aim of the study was to evaluate ADV antibody prevalence in the Polish wild boar population, during the years 2011 to 2014. Material and Methods: Wild boar blood samples were collected during three consecutive hunting seasons; i.e. 2011/2012, 2012/2013, and 2013/2014, and tested for ADV antibodies by ELISA. Results: ADV antibodies were detected in samples from all tested voivodships. The average seroprevalence reached 32.2%. Seroprevalence, over the examined hunting seasons, was 27.4% in 2011/2012, 32.4% in 2012/2013, and 35.5% in 2013/2014. The highest percentage of seroreagents was detected in four voivodships, situated along the western border of Poland, i.e. Zachodnio-Pomorskie (ZP), Lubuskie (LB), Dolnośląskie (DS), and Opolskie (OP). This area is positively correlated with the highest density of the wild boar population and the highest wild boar hunting bag. Conclusion: The results of this study confirm that the wild boar population may still pose a threat to domestic pigs, which is of special importance at the final stage of Aujeszky’s disease eradication programme in Poland.

Introduction: A novel to Europe Schmallenberg virus (SBV) causes clinical disease manifested by reproduction disorders in farm ruminants. In free-living ruminants, SBV antibodies as well as the virus were detected. Recent studies also revealed SBV antibodies in wild boars. The study investigates SBV antibodies occurring in wild boars in Poland at the peak of recent virus epidemics in the country.Material and Methods: Samples collected from 203 wild boars culled during the 2012/2013 and 2013/2014 hunting season were serologically tested using multi-species cELISA. Attempted neutralisation tests failed due to poor serum quality. RT-PCR was implemented in seropositive and doubtful animals.Results: Two samples collected from wild boar in the winter of 2013 gave a positive result in ELISA, while another two from the 2012/2013 hunting season were doubtful. No SBV RNA was detected in spleen and liver tissues.Conclusion: Low SBV seroprevalence in wild boars, despite high incidence of SBV infections occurring simultaneously in wild ruminants, suggests that boars are unlikely to be a significant reservoir of the virus in the sylvatic environment in Poland.

Introduction: The objective was to evaluate the epizootic and epidemiological situation of Trichinella sp. infection in Poland between 2006 and 2015 against the dynamics of the wild boar population and its primary reservoir host.Material and Methods: Boar and porcine trichinosis epizootic analysis was based on General Veterinary Inspectorate data from RRW-6 bulletins. The epidemiological situation was evaluated on the basis of the data supplied by the Department of Epidemiology of the National Institute of Hygiene - National Institute of Public Health. The wild boar hunting harvest and population dynamics were estimated, as these animals remain the basic infection source for humans. Population size and harvest data were obtained from hunting statistics.Results: The study timeframe showed an almost 2.5-fold increase in Trichinella infection cases in wild boars but a significant decline in human cases. In the domestic pig, the incidence rate did not exceed 0.00037%. The highest infection risk exists in West Pomerania, Greater Poland, and Kuyavian-Pomeranian Provinces. Over the study period, the wild boar population increased more than 1.5-fold, while the hunting harvest more than tripled. During the last two seasons the total hunt surpassed 100% of the spring population.Conclusion: Wild boar management by increasing the hunting take of the annual population growth should limit that growth and decrease the take in the future. Thereby, over some years intra-species trichinosis spread should reduce, for a substantial safety gain for wild boar meat.

Introduction: The objective was to evaluate the epizootic and epidemiological situation of Trichinella sp. infection in Poland between 2006 and 2015 against the dynamics of the wild boar population and its primary reservoir host.

Introduction: Aujeszky’s disease (AD), most often related to infection of domestic and feral swine, may also concern other mammals, including dogs. The disease in carnivores, related to consumption of raw meat or offal contaminated with AD virus, is manifested by severe neurological disorders and inevitably leads to animal’s death.

Animal tuberculosis (TB) is a zoonotic disease caused by acid-fast bacteria belonging to the Mycobacterium tuberculosis complex (MTBC). Both animals and humans are susceptible to infection by the MTBC. Interspecies transmission is also possible, including to livestock and humans. In the years 1997–2013, many tuberculosis cases were recorded in European bison in the Bieszczady Mountains; more alarmingly, TB was also recorded in wild boar in the years 2013–2020.

Porcine epidemic diarrhoea virus (PEDV) of the Coronaviridae family causes significant economic losses in the pig industry worldwide. Wild boars contribute to the transmission of different viral, bacterial and parasitic infections to livestock animals and humans. However, their role in the maintenance and transmission of PEDV has not been established. In this study, blood and faecal samples from 157 wild boars were collected from 14 provinces of Poland during the 2017–2018 hunting season. RNA was extracted from the faecal homogenate supernatant and subjected to quantitative RT-PCR (RT-qPCR), while clotted blood samples were used for detection of antibodies against PEDV by ELISA. Five blood samples (3.2%) were seropositive in ELISA, while none of the faecal samples were found positive using RT-qPCR assays. The results of this analysis indicate the need for additional studies incorporating a larger number of samples and preferably comparing different serological methods, to confirm whether wild boars in Poland act as PEDV reservoirs.

Porcine epidemic diarrhoea virus (PEDV) of the Coronaviridae family causes significant economic losses in the pig industry worldwide. Wild boars contribute to the transmission of different viral, bacterial and parasitic infections to livestock animals and humans. However, their role in the maintenance and transmission of PEDV has not been established.