African Swine Fever in a Bulgarian Backyard Farm—A Case Report
Abstract
:1. Introduction
2. Methodology
3. Case Description
3.1. Settings
3.2. Timeline of the Disease Event
3.3. Control Measures
3.4. Genetic Analysis
4. Discussion
4.1. High-Risk Period
4.2. Potential Spreading Scenario
4.3. Biosecurity and Potential Introduction Pathways
4.4. Applied Control Measures
5. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Animal ID | Date of Death | qPCR | Antibody Detection | Virus Isolation | Tested Specimen |
---|---|---|---|---|---|
Pregnant sow #1 | Aug 16 | positive | n/a | n/a | tissue sample (decomposed) |
Fattening pig #2 | Aug 27 | positive | n/a | n/a | tissue sample (decomposed) |
Pregnant sow #3 | Aug 28 | positive | n/a | n/a | tissue sample (decomposed) |
Boar #4 | Aug 29 | positive | positive | positive | spleen, kidney, lymph node |
Fattening pig #5 | Aug 31 (culled) | positive | weakly positive | positive | blood |
Fattening pig #6 | Aug 31 (culled) | positive | negative | positive | blood |
Fattening pig #7 | Aug 31 (culled) | negative | negative | n/a | blood |
Hypothetical Introduction Route | Risk Factors | Description | Probability of Introduction Pathway |
---|---|---|---|
1. Contact to contaminated fomites/food | Feeding regime | According to the farmer, no swill was fed to the pigs. No ASF has been detected in other pig farms of the village having the same food supply. | Moderate |
Anthropogenic factor | Access to stable not restricted for anyone who had access to the farmers yard. In case of the farmer’s absence, colleagues were taking care of the animals. | High | |
2. Link to infected wild boar | Setup of the farm | The animal facilities are located inside the garden surrounding the farmer’s house. The area is enclosed by a stonewalled fence. No evidence for direct contact with wild boar within the farm. | Negligible |
Indirect contact with wild boar environment | The first ASF case in wild boar within the region has been detected 5 months after the described outbreak. Still it cannot be excluded that the disease has been present in the population before then. | Moderate | |
Anthropogenic factor | The owner has a hunting license but did not go hunting in the last 15 years. | Low | |
3. Animal movement | Introduction of infected animals | All pigs have been purchased in 2017. | Negligible |
Animal movement | The last movement of the boar for breeding purposes was three months before the outbreak. | Negligible |
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Zani, L.; Dietze, K.; Dimova, Z.; Forth, J.H.; Denev, D.; Depner, K.; Alexandrov, T. African Swine Fever in a Bulgarian Backyard Farm—A Case Report. Vet. Sci. 2019, 6, 94. https://doi.org/10.3390/vetsci6040094
Zani L, Dietze K, Dimova Z, Forth JH, Denev D, Depner K, Alexandrov T. African Swine Fever in a Bulgarian Backyard Farm—A Case Report. Veterinary Sciences. 2019; 6(4):94. https://doi.org/10.3390/vetsci6040094
Chicago/Turabian StyleZani, Laura, Klaas Dietze, Zlatina Dimova, Jan Hendrik Forth, Daniel Denev, Klaus Depner, and Tsviatko Alexandrov. 2019. "African Swine Fever in a Bulgarian Backyard Farm—A Case Report" Veterinary Sciences 6, no. 4: 94. https://doi.org/10.3390/vetsci6040094