{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T14:13:29Z","timestamp":1787840009058,"version":"build-2784847793"},"reference-count":20,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2020,3,22]],"date-time":"2020-03-22T00:00:00Z","timestamp":1584835200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004281","name":"Narodowe Centrum Nauki","doi-asserted-by":"publisher","award":["UMO-2016\/21\/D\/NZ6\/00974"],"award-info":[{"award-number":["UMO-2016\/21\/D\/NZ6\/00974"]}],"id":[{"id":"10.13039\/501100004281","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>This paper was aimed to characterize clinical signs and pathomorphological lesions in twenty-two pigs, infected intranasally by different doses of African swine fever virus (Pol18_28298_O111), isolated during the outbreak in a pig farm that occurred in Eastern Poland throughout 2018. This article also attempts to indicate risk, related to virus load and shedding, and present possible difficulties with proper disease recognition at the farm level. The results revealed that even a very low dose (5 HAU) may initiate the infection. Various forms of the disease (acute, subacute, and chronic), mainly with prodromal clinical signs like fever, apathy, and reduced feed intake were observed. The most frequently observed lesions (82%) were: hyperemia and enlargement of lymph nodes and splenomegaly. The minimal incubation period was estimated at five days post-infection (dpi). Mortality ranged from 80\u2013100%. Two pigs survived the infection. Some viremic animals presented delayed fever. In some cases, the fever was not detectable. Shortly after viremia, the virus was secreted ion the urine, feces, and saliva. The highest levels of virus were found in the internal organs and blood; however in the case of one pig (chronic form), viral DNA was not detected in the spleen, liver, bone marrow, and brain. Veterinary diagnosis may be difficult, and the final results should always be based on laboratory investigations.<\/jats:p>","DOI":"10.3390\/pathogens9030237","type":"journal-article","created":{"date-parts":[[2020,3,23]],"date-time":"2020-03-23T04:03:01Z","timestamp":1584936181000},"page":"237","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":44,"title":["Analysis of the Clinical Course of Experimental Infection with Highly Pathogenic African Swine Fever Strain, Isolated from an Outbreak in Poland. Aspects Related to the Disease Suspicion at the Farm Level"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2991-9964","authenticated-orcid":false,"given":"Marek","family":"Walczak","sequence":"first","affiliation":[{"name":"Department of Swine Diseases, National Veterinary Research Institute, Partyzant\u00f3w 57 Avenue, 24-100 Pu\u0142awy, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jacek","family":"\u017bmudzki","sequence":"additional","affiliation":[{"name":"Department of Swine Diseases, National Veterinary Research Institute, Partyzant\u00f3w 57 Avenue, 24-100 Pu\u0142awy, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Natalia","family":"Mazur-Panasiuk","sequence":"additional","affiliation":[{"name":"Department of Swine Diseases, National Veterinary Research Institute, Partyzant\u00f3w 57 Avenue, 24-100 Pu\u0142awy, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5705-4099","authenticated-orcid":false,"given":"Ma\u0142gorzata","family":"Juszkiewicz","sequence":"additional","affiliation":[{"name":"Department of Swine Diseases, National Veterinary Research Institute, Partyzant\u00f3w 57 Avenue, 24-100 Pu\u0142awy, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Grzegorz","family":"Wo\u017aniakowski","sequence":"additional","affiliation":[{"name":"Department of Swine Diseases, National Veterinary Research Institute, Partyzant\u00f3w 57 Avenue, 24-100 Pu\u0142awy, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,3,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1016\/j.tvjl.2017.12.025","article-title":"African swine fever: A re-emerging viral disease threatening the global pig industry","volume":"233","author":"Montoya","year":"2018","journal-title":"Vet. J."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"17","DOI":"10.2478\/jvetres-2019-0006","article-title":"Characteristics of selected active substances used in disinfectants and their virucidal activity against ASFV","volume":"63","author":"Juszkiewicz","year":"2019","journal-title":"J. Vet. Res."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"150","DOI":"10.1016\/j.virusres.2019.03.022","article-title":"Development of vaccines against African swine fever virus","volume":"265","author":"Revilla","year":"2019","journal-title":"Virus Res."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Dixon, L.K., Stahl, K., Jori, F., Vial, L., and Pfeiffer, D.U. (2019). African Swine Fever Epidemiology and Control. Annu. Rev. Anim. Biosci., 1\u201326.","DOI":"10.1146\/annurev-animal-021419-083741"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1870","DOI":"10.3201\/eid1412.080591","article-title":"African Swine Fever Virus Isolate, Georgia, 2007","volume":"14","author":"Rowlands","year":"2008","journal-title":"Emerg. Infect. Dis."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"8490","DOI":"10.1038\/s41598-019-44890-0","article-title":"Analysis of Estonian surveillance in wild boar suggests a decline in the incidence of African swine fever","volume":"9","author":"Schulz","year":"2019","journal-title":"Sci. Rep."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"197614","DOI":"10.1016\/j.virusres.2019.04.001","article-title":"Pathogenesis of African swine fever in domestic pigs and European wild boar \u2013 Lessons learned from recent animal trials","volume":"271","author":"Pikalo","year":"2019","journal-title":"Virus Res."},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Pershin, A., Shevchenko, I., Igolkin, A., Zhukov, I., Mazloum, A., Aronova, E., Vlasova, N., and Shevtsov, A. (2019). A long-term study of the biological properties of ASF virus isolates originating from various regions of the russian federation in 2013-2018. Vet. Sci., 6.","DOI":"10.3390\/vetsci6040099"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"612","DOI":"10.1111\/tbed.12431","article-title":"Experimental Transmission of African Swine Fever (ASF) Low Virulent Isolate NH\/P68 by Surviving Pigs","volume":"62","author":"Gallardo","year":"2015","journal-title":"Transbound. Emerg. Dis."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Gallardo, C., and Arias, M. (2019). African swine fever (ASF) diagnosis, an essential tool in the epidemiological investigation. Virus Res., 271.","DOI":"10.1016\/j.virusres.2019.197676"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"9","DOI":"10.1016\/j.jcpa.2014.09.003","article-title":"An update on the epidemiology and pathology of African swine fever","volume":"152","author":"Mur","year":"2015","journal-title":"J. Comp. Pathol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1657","DOI":"10.1007\/s00705-015-2430-2","article-title":"Course and transmission characteristics of oral low-dose infection of domestic pigs and European wild boar with a Caucasian African swine fever virus isolate","volume":"160","author":"Pietschmann","year":"2015","journal-title":"Arch. Virol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"92","DOI":"10.1016\/j.vetmic.2017.10.004","article-title":"Transmission of African swine fever virus from infected pigs by direct contact and aerosol routes","volume":"211","author":"Olesen","year":"2017","journal-title":"Vet. Microbiol."},{"key":"ref_14","first-page":"1","article-title":"Clinical and post-mortem investigations of genotype II induced African swine fever","volume":"5","author":"Karalova","year":"2015","journal-title":"Porc. Res."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"891","DOI":"10.3201\/eid2505.181495","article-title":"Infectious Dose of African Swine Fever Virus When Consumed Naturally in Liquid or Feed","volume":"25","author":"Niederwerder","year":"2019","journal-title":"Emerg. Infect. Dis."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"300","DOI":"10.1111\/tbed.12346","article-title":"Experimental Infection of Domestic Pigs with African Swine Fever Virus Lithuania 2014 Genotype II Field Isolate","volume":"64","author":"Gallardo","year":"2017","journal-title":"Transbound. Emerg. Dis."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"126","DOI":"10.1016\/j.prevetmed.2018.11.013","article-title":"Survival of African swine fever virus (ASFV) in various traditional Italian dry-cured meat products","volume":"162","author":"Petrini","year":"2019","journal-title":"Prev. Vet. Med."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"6510","DOI":"10.1038\/s41598-018-24740-1","article-title":"Deletion at the 5\u2019-end of Estonian ASFV strains associated with an attenuated phenotype","volume":"8","author":"Zani","year":"2018","journal-title":"Sci. Rep."},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"S\u00e1nchez-Cord\u00f3n, P.J., Nunez, A., Neimanis, A., Wikstr\u00f6m-Lassa, E., Montoya, M., Crooke, H., and Gavier-Wid\u00e9n, D. (2019). African swine fever: Disease dynamics in wild boar experimentally infected with ASFV isolates belonging to genotype I and II. Viruses, 11.","DOI":"10.3390\/v11090852"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"425","DOI":"10.1111\/tbed.12381","article-title":"Survival of African Swine Fever Virus in Excretions from Pigs Experimentally Infected with the Georgia 2007\/1 Isolate","volume":"64","author":"Davies","year":"2017","journal-title":"Transbound. Emerg. 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