First Report on Co-isolation and Whole-genomic Characterization of Mammalian Orthorubulavirus 5 and Mammalian Orthoreovirus Type-3 From Domestic Pigs in India

During a surveillance study to monitor porcine epidemic diarrohoea virus and transmissible gastroenteritis virus in India, a total of 1043 swine samples including faeces (n=264) and clotted blood (n=779) were collected and tested. Five samples (four faecal and one serum) showed cytopathic effects in Vero cells. Transmission electron microscopy of infective cell supernatant revealed the presence of two types of virions. Next generation sequencing (de novo) enabled complete genome assembly of Mammalian orthorubulavirus 5 (MRuV5; 15246 bp) and all 10 gene segments of Mammalian orthoreovirus (MRV; 22219 bp and 20512 bp). Genetic analysis of the MRuV5 revealed grouping of the Indian MRuV5 with those isolated from various mammalian species in South Korea and China, sharing more than 99% nucleotide identity. Deduced amino acid sequences of the HN, NP and F genes of MRuV5 isolates showed three (92L, 111R, 447H), two (86S, 121S) and two (139T, 246T) amino acid substitutions, respectively, compared to previously reported virus strains. The Indian MRV isolates were identified as MRV type-3 based on genetic analysis of S1 gene, showing the highest nucleotide identity (97.73%) with the MRV3 strain ZJ2013 isolated from pigs in China. Deduced amino acid sequences of MRV3 S1 gene revealed amino acid residues 198-204NLAIRLP, 249I, 340D, 419E known for sialic acid binding and neurotropism. We report the co-isolation and whole-genomic characterization of MRuV5 and MRV3 recorded incidentally for the first time from domestic pigs in India. It attracts attention to perform detailed surveillance studies and continuous monitoring of evolution and spread of emerging viruses, which may have pathogenic potential in animal and human hosts.

Characterization and management of interaction risks between livestock and wild ungulates on outdoor pig farms in Spain

Background To control the transmission of relevant shared diseases, such as animal tuberculosis (TB) and African swine fever (ASF), it is essential to reduce the risk of interaction between livestock and wild ungulates. In Eastern and Central Europe, the current spread of ASF virus affecting wild boar and domestic pigs (especially those raised outdoors and/or in backyards) has devastated the pig sector in affected regions and is seriously threatening other exporting countries. Here, we evaluated the risk of wildlife-livestock interactions on 45 outdoor pig farms in Spain, the second largest pork producer in the EU and then proposed biosecurity-related actions. An integrated, systematic wildlife risk mitigation protocol based on interviews, questionnaires and field audits was developed and applied on each farm. Results Most of the interaction risk points were associated with water sources (84.2%; 701/832), mainly springs and ponds, which accounted for almost all the specific points with high or very high risk scores. The risk of interaction at feeding points (6.9%; 57/832) and those associated with facilities for livestock and/or game management (8.9%; 74/832) were rated as low and very low risk, respectively. Wild boar were present and hunted on 69% of the farms. Supplementary feeding for wild ungulate species (mainly wild boar) was provided on almost half (48.9%; 22/45) the surveyed farms. Risk mitigation actions were categorised to target water access, waterers, food, other livestock species, grazing, wildlife, and offal disposal. Of the total number of actions (n = 2016), 82.7% were identified as priority actions while 17.3% represented alternative options which were identified less cost-effective. On average, 37.1 (median: 32; range 14–113) action proposals per study farm were made and 2.0 (median: 1; range 0–4) per risk point. The mean estimated cost of implementing the proposed priority actions was 14,780 €/farm (25.7 €/hectare and 799.4 €/risk point). Conclusions This study expands the knowledge of interaction risks between domestic pigs and wild ungulates in outdoor pig farming systems and highlights the importance of considering local risks and management practices when designing and prioritising adapted wildlife risk mitigation and biosecurity actions. This practical and feasible protocol developed for Mediterranean ecosystems is easily transferable to professionals and can be adapted to extensive (outdoor) production or epidemiological systems in other European regions.

African Swine Fever Outbreaks in Lithuanian Domestic Pigs in 2019

While numerous risk factors of African swine fever (ASF) transmission to domestic pigs have been described, ASF virus introduction has often not been traced back to one single defined cause. The large number of ASF outbreaks that occurred in domestic pigs in Lithuania from 2014 through to 2018 raised the question regarding whether outbreak-specific risk factors and transmission routes could be identified. Therefore, a prospective matched case-control study was designed. Data from 18 outbreaks that occurred in Lithuanian in 2019 and 36 control farms were analyzed. Conditional multivariable logistic regression showed that two or more visits by veterinary inspection of a farm had a significant preventive effect on the occurrence of ASF on a farm (Odds ratio (OR) 14.21, confidence interval (CI) 1.09–185.60 for farms not inspected vs. farms inspected twice or more a year), while certain practices (e.g., mushroom picking, sharing equipment, etc.), which might facilitate the indirect introduction of ASF from fields and forests into piggeries, significantly increased the odds of an outbreak (OR 5.18, CI 1.10–24.44). The results of the study highlight the importance of veterinary inspections for increasing the biosecurity level on pig farms and the awareness of ASF. The knowledge on potential protective and risk factors may help to improve the prevention and control of ASF outbreaks in domestic pig farms in Lithuania and other affected countries.

Lungworms (Metastrongylus Spp.) Demonstrated in Domestic Pigs with Respiratory Disease - What was the True Relevance of that?

BackgroundAn outdoor pig herd was affected by severe respiratory disease in one out of three pastures. At necropsy, Mycoplasma hyopneumoniae and Pasteurella multocida were detected in the lungs, as well as the lung worm Metastrongylus apri. The life cycle of Metastrongylus spp. includes earth worms as an intermediate host, and since domesticated pigs mainly are reared indoors lungworms has not been diagnosed in domestic pigs in Sweden for decades, not even in pigs reared outdoors. Therefore, this disease outbreak was scrutinised from the view of validating the impact of Metastrongylus spp..ResultsAt the time of the disease outbreak, neither eggs of Metastrongylus spp. nor Ascaris suum were detected in faeces of pigs aged ten weeks. In contrast, five-months-old pigs at the pasture with respiratory disease shed large amounts of eggs from Ascaris suum, whereas Ascaris suum not was demonstrated in healthy pigs aged six months at another pasture. Low numbers of eggs from Metastrongylus spp. were seen in faecal samples from both these age categories.At slaughter, seven weeks later, ten normal weighted pigs in the preceding healthy batch were compared with ten normal weighted and five small pigs from the affected batch. Healing Mycoplasma-like pneumonic lesions were seen in all groups. Small pigs had more white spot liver lesions, and all small pigs shed eggs of Ascaris suum in faeces, compared to around 50% of the pigs in the normally sized groups. Metastrongylus spp. were demonstrated in 13 of the 25 pigs (52%), %), representing all groups included.ConclusionAs Metastrongylus spp. were demonstrated regardless of health status, and in another healthy outdoor herd, the impact of Metastrongylus spp. on the outbreak of respiratory disease was depreciated. Instead, Metastrongylus spp. was suggested to be common in outdoor production, although rarely diagnosed. The reason for this is because they will escape detection at routine inspection at slaughterhouses, and that they appeared to generally not induce clinical signs of respiratory disease. Instead, a possible association with a high burden of Ascaris suum was suggested to have preceded the severe outbreak with respiratory disease.

I267L Is Neither the Virulence- Nor the Replication-Related Gene of African Swine Fever Virus and Its Deletant Is an Ideal Fluorescent-Tagged Virulence Strain

African swine fever virus (ASFV) is the causative agent of African swine fever (ASF) which reaches up to 100% case fatality in domestic pigs and wild boar and causes significant economic losses in the swine industry. Lack of knowledge of the function of ASFV genes is a serious impediment to the development of the safe and effective vaccine. Herein, I267L was identified as a relative conserved gene and an early expressed gene. A recombinant virus (SY18ΔI267L) with I267L gene deletion was produced by replacing I267L of the virulent ASFV SY18 with enhanced green fluorescent protein (EGFP) cassette. The replication kinetics of SY18ΔI267L is similar to that of the parental isolate in vitro. Moreover, the doses of 102.0 TCID50 (n = 5) and 105.0 TCID50 (n = 5) SY18ΔI267L caused virulent phenotype, severe clinical signs, viremia, high viral load, and mortality in domestic pigs inoculated intramuscularly as the virulent parental virus strain. Therefore, the deletion of I267L does not affect the replication or the virulence of ASFV. Utilizing the fluorescent-tagged virulence deletant can be easy to gain a visual result in related research such as the inactivation effect of some drugs, disinfectants, extracts, etc. on ASFV.

Territorial pattern between outbreaks of ASF among wild and domestic pigs in Ukraine

The article presents the results of the analysis of the epizootic situation in Ukraine regarding African swine fever among domestic and wild pigs from 2012 to 2020 and identifies the main sources of virus spread as well as weak links in the biological safety system of farms. When studying the statistical material of the Food and Agriculture Organization of the United Nations (FAO) and the State Service of Ukraine on Food Safety and Consumer Protection regarding animal morbidity, revealed a territorial pattern between the outbreaks of African swine fever among wild boars and domestic pigs of private farms and pig-breeding complexes, and proved the involvement of the European boar in the epizootic process as a natural reservoir and mobile focus of infection. Calculated the number of outbreaks of African swine fever among wild boars and domestic pigs within the same region and district, and studied the sequence of the emergence of foci on limited territories. Analyzed the natural focality of the disease, the probability of infection transmission to the domestic pig farm sector, and the role of infected objects in the spread of the virus among wild animal populations. From 2012 to 2020 inclusive, according to FAO statistics, 537 cases of African swine fever were recorded in Ukraine, 21.7 % of which were associated with wild boars. In 2017 and 2018, the role of the European wild boar in the epizootic process is best reflected, when 10.9 % (2017) and 20.4 % (2018) of outbreaks of African swine fever among domestic animals recorded in the same administrative districts, where during a year this desiase was detected among wild pigs. When analyzing statistical data of the recent years, the effectiveness of introducing more detailed monitoring of African swine fever among wild boars using modern laboratory methods and improving biosafety measures in the private sector and directly on hunting grounds has been proved. Further research is based on predicting the dynamics of the spread of African swine fever in Ukraine and the role of wild boar in this epizootic process. In addition, the role of wild boar in the spread of African swine fever in other countries and the most effective foreign methods of disease control and prevention will be analyzed.

Updated distribution and host records for the argasid tick Ornithodoros (Pavlovskyella) zumpti: A potential vector of African swine fever virus in South Africa

African swine fever virus (ASFV) causes a lethal and contagious disease of domestic pigs. In South Africa, the virus historically circulated in warthogs and ornithodorid ticks that were only found in warthog burrows in the north of the country. Regulations implemented in 1935 to prevent transfer of infected animals or products to the south initially proved effective but from 2016 there have been outbreaks of disease in the south that cannot be traced to transfer of infection from the north. From 1963 there were widespread translocations of warthogs to the south, initially from a source considered to be free of ornithodorid ticks. We undertook to determine whether sylvatic circulation of ASFV occurs in the south, including identification of potential new vectors, through testing extralimital warthogs for antibody and ticks for virus. Results of testing warthogs for antibody and other species of ticks for virus will be presented separately. Here we report finding Ornithodoros (Pavlovskyella) zumpti ticks in warthog burrows for the first time. This occurred in the Eastern Cape Province (ECP) in 2019. Since African swine fever was recognised in the ECP for the first time in 2020 and outbreaks of the disease in domestic pigs continue to occur there, priority should be given to determining the distribution range and vector potential of O. (P.) zumpti for ASFV.

Key risk factors and impact of African swine fever spreading on pig production in Serbia

African swine fever (ASF) is a viral disease of domestic pigs and wild boars and currently represents a major threat to the swine industry worldwide. Disease control is impaired by a lack of an effective vaccine and currently, it is dependent on biosecurity measures in pig production, rapid diagnosis, and stamping out of infected herds. Consequently, this swine disease has considerable social-economic significance on national or even regional level. In 2019 for the first time ASF was detected in the domestic swine population (backyards) in the central region of Serbia. From then on, there have been continuous outbreaks of new cases in the population of domestic and wild boars. Considering domestic pig population, in the majority of cases, ASF was detected in small holdings and backyards. The biosecurity measures are not officially required by veterinary regulation and are only given in a form of recommendations. On the other hand, it is not always possible to implement biosecurity measures that are recognized today as essential for sustainable pig production in the old type of industrial pig facilities. Nowadays, in 2021, it became obvious that the domestic pig cycle, human activities involving pigs, or pig-derived meat products are the dominant driver of virus transmission. Additionally, human activities are frequently a risky connection between domestic pigs and wild boars both directly or indirectly. Traditional, culture-related aspects and facts that politicians failed to recognise ASF as a serious issue that causes great economical losses were found to be very important obstacles in disease control.

Prevalence and Phylogenetic Analysis of Babesia Parasites in Reservoir Host Species in Fujian Province, Southeast China

Background: Babesiosis is a tick-borne disease that mainly affects small mammals and it has been reported in at least five provinces in China. However, the host range and geographical distribution of the parasite in Fujian Province are unclear. Therefore, this study aimed to investigate the prevalence and genetic characteristics of Babesia in Fujian Province, Southeast China, between 2015 and 2020.Methods: Rodent blood samples were collected from 26 different surveillance sites across Fujian Province. Genomic DNA was extracted to screen for Babesia infection using polymerase chain reaction (PCR) amplification, based on 18S rRNA. DNA samples from 316 domestic goats, 85 water buffalo, 56 domestic dogs, and 18 domestic pigs were examined. The prevalence of Babesia was statistically analyzed using the Chi-square test or Fisher’s exact test. A phylogenetic tree was constructed using MEGA 5.0 by gene sequence alignment.Results: Babesia infections were found in 3.96% (43/1,087) of rodents and 1.26% (6/475) of other mammals. Multivariate logistic regression analysis revealed that irrigated cropland, shrubs, and forests were risk factors for Babesia microti infections. The infection rates among domestic pigs, dogs, and goats were found to be 5.56%, 1.79%, and 1.27%, respectively, and no infection was found in water buffalo. Sequencing (18S rRNA gene) revealed that rodents were infected with Babesia (sensu lato) while other mammals were infected with Babesia (sensu stricto).Conclusions: The results indicate that there is wide geographical distribution and phylogenetic relationship of Babesia in Southeast China. This study suggests that mammals, especially wild rodents, are the main natural hosts of Babesia in Fujian. Our findings provide a solid foundation for public health officials to develop Babesia prevention and control measures.