Classical swine fever

Classical swine fever (CSF) or hog cholera is a highly contagious viral disease of swine (pigs and wild boar). Wageningen Bioveterinary Research conducts research on this disease.

Spread of the disease

Transmission of classical swine fever takes place through direct contact between animals (secretions, excretions, semen, blood) or indirect contact through vehicles, clothes, instruments, needles, and insufficiently cooked waste food fed to pigs. It can also be spread by pig traders and farm visitors. Transplacental infection of foeti in the uterus can also take place. In areas with a high density of pigs spread of virus easily occurs between neighbouring pig holdings. Trade in live pigs and pig products (fresh pig meat and certain meat-based products) plays an important role in spreading the disease.

Clinical signs

The clinical signs of classical swine fever are extremely variable and may be mistaken for many other diseases. CSF causes fever, conjunctivitis, skin lesions, convulsions and often (particularly in young animals) leads to death of the animal within less than four weeks.

Severity of symptoms mainly depends on the age of the animal and virus virulence. Usually young animals are affected more severely than older animals. In older breeding pigs the course of the infection is often mild or even subclinical. The symptoms are indistinguishable from those of African swine fever.






Monger, V. R., Stegeman, J. A., Dukpa, K., Gurung, R. B., Loeffen, W. L.  2016. Evaluation of Oral Bait Vaccine Efficacy Against Classical Swine Fever in Village Backyard Pig Farms in Bhutan. Transbound. Emerg. Dis. 63: e211-e218. WOT-01-003-010

Guo, Xuezhen, Claassen, G.D.H., Oude Lansink, A.G.J.M., Loeffen, W., Saatkamp, H.W. 2016. Economic analysis of Classical Swine Fever surveillance in the Netherlands. Transbound. Emerg. Dis. 63: 296-313. WOT-01-003-010. DOI: 10.1111/tbed.12274

der Wal FJ, Jelsma, T, Fijten H, Achterberg RP, Loeffen WL Towards a peptide-based suspension array for the detection of pestivirus antibodies in swine. J Vir Met. WOT-01-003-010-01

Eefke Weesendorp, Jantien Backer, Willie Loeffen. 2014. Quantification of different classical swine fever transmission routes within a single compartment. Vet. Microbiol. 174: 353-361.

P.L. Eblé, S. Quak, Y. Geurts, H.W. Moonen-Leusen, W.L.A. Loeffen. 2014. Efficacy of CSF vaccine CP7_E2alf in piglets with maternally derived antibodies. Vet. Microbiol. 174: 27-38.

Monger, V.R., Stegeman, J.A., Koop, G., Dukpa, K., Tenzin, T., Loeffen, W.L.A. 2014. Seroprevalence and associated risk factors of important pig viral diseases in Bhutan. Prev. Vet. Med. 117: 222-232.

Boender, G. J., van den Hengel, R, van Roermund, H. J., Hagenaars, T. J. 2014. The Influence of Between-Farm Distance and Farm Size on the Spread of Classical Swine Fever during the 1997-1998 Epidemic in The Netherlands. PLoS ONE 9(4): e95278. doi:10.1371/journal.pone.0095278.

Batonick M, Loeffen W, Metwally SA, Mayr GA. 2013. Identification and characterization of mimotopes of classical swine fever virus E2 glycoprotein using specific anti-E2 monoclonal antibodies. Virus Res. 175: 12-19.

J.A. Backer, R. Vrancken, J. Neyts, N. Goris. 2013. The potential of antiviral agents to control classical swine fever: A modelling study. Antiviral Res.99 245-250.

Hulst, M., Loeffen, W., Weesendorp, E. 2013. Pathway analysis in blood cells of pigs infected with classical swine fever virus: comparison of pigs that develop a chronic form of infection or recover, Arch. Virol. 158: 325-339.

P.L. Eblé, Y. Geurts, S. Quak, H.W. Moonen-Leusen, S. Blome, M.A. Hofmann, F. Koenen, M. Beer, W.L.A. Loeffen. 2013. Efficacy of chimeric Pestivirus vaccine candidates against Classical Swine Fever: protection and DIVA characteristics. Vet Microbiol. 162: 437-446.

Elbers, A.R.W., Loeffen, W.L.A., Koch, G. 2012. Classical swine fever and avian influenza epidemics: lessons learned. Berl. Münch. Tierärtzl. Wochenschr.125: 21-26.( Proj. BAS nr. WOT-01-001-004).

Hoffmann B, Blome S, Bonilauri P, Fernández-Piñero J, Greiser-Wilke I, Haegeman A, Isaksson M, Koenen F, Leblanc N, Leifer I, Le Potier MF, Loeffen W, Rasmussen TB, Stadejek T, Ståhl K, Tignon M, Uttenthal A, van der Poel W, Beer M. 2011. Classical swine fever virus detection: results of a real-time reverse transcription polymerase chain reaction ring trial conducted in the framework of the European network of excellence for epizootic disease diagnosis and control. J. Vet Diagn. Invest. 23: 999-1004.

Geenen, P.L., van der Gaag, L.C., Loeffen, W.L.A., Elbers, A.R.W. 2011. Constructing naive Bayesian classifiers for veterinary medicine: A case study in the clinical diagnosis of classical swine fever. Res. Vet. Sci. 91: 64-70. Project BAS nr: WOT-01-001-004.

Backer JA, Brouwer H, van Schaik G, van Roermund HJW. 2011. Using mortality data for early detection of Classical Swine Fever in The Netherlands. Prev. Vet.  Med. 99: 38-47. Project BAS nrs BO-08-010-011

Kortekaas J., Ketelaar J., Vloet, R.P.M., Loeffen W.L. 2011. Protective efficacy of a Classical swine fever virus C-strain deletion mutant and ability to differentiate infected from vaccinated animals. Vet. Microbiol. 147: 11-18

Weesendorp, E., Backer, J., Stegeman, J.A., Loeffen, W.L.A. 2011.Transmission of classical swine fever virus depends on the clinical course of infection which is associated with high and low level of virus excretion. Vet. Microbiol. 147: 262-273

Eefke Weesendorp, Willie Loeffen, Arjan Stegeman, Clazien de Vos. 2011. Time-dependent infection probability of classical swine fever via excretions and secretions. Prev. Vet. Med. 98: 152-164

A.R.W. Elbers, M.J. Gorgievski-Duijvesteijn, P.G. van der Velden, W.L.A. Loeffen, K. Zarafshani. A socio-psychological investigation into limitations and incentives concerning reporting a clinically suspect situation aimed at improving early detection of classical swine fever outbreaks. Veterinary Microbiology 142 (2010) 108–118

Weesendorp, E., Willems, E., Loeffen, W.L.A. The effect of tissue degradation on detection of infectious virus and viral RNA to diagnose classical swine fever virus. Vet Microbiol. 2010 Mar 24;141(3-4):275-281

Kortekaas, J., Vloet, R.P.M., Weerdmeester, K., Ketelaar, J., van Eijk, M., Loeffen, W.L. Rational design of a classical swine fever C-strain vaccine virus that enables the differentiation between infected and vaccinated animals. Journal of Virological Methods, 2010 Feb;163(2):175-85..

Backer, J.A., Hagenaars, T.J., van Roermund, H.J.W., de Jong, M.C.M. 2009. Modelling the effectiveness and risks of vaccination strategies to control classical swine fever epidemics. Journal of the Royal Interface 6: 849-861

Weesendorp, E., Backer, J., Stegeman, J.A., Loeffen, W.L.A. Effect of strain and inoculation dose of classical swine fever virus on within-pen transmission. Vet Research. 2009 Nov-Dec;40(6):59.

Brookes SM, Irvine RM, Nunez A, Clifford D, Essen S, Brown IH, Van Reeth K, Kuntz-Simon G, Loeffen, WLA, A. van Beuningen, S. Quak, A.R.W. Elbers. Seroprevalence and risk factors for the presence of ruminant pestiviruses in the Dutch swine population. Vet Microbiol. 2009 May 12;136(3-4):240-5.

Weesendorp, E., Stegeman, A., Loeffen, W. Quantification of classical swine fever virus in aerosols originating from pigs infected with strains of high, moderate or low virulence. Vet Microbiol. 2009 Mar 30;135(3-4):222-30.

Weesendorp, E., Stegeman, A., Loeffen, W.L., Dynamics of virus excretion via different routes in pigs experimentally infected with classical swine fever virus strains of high, moderate or low virulence, Vet Microbiol. 2009 Jan 1;133(1-2):9-22.

Weesendorp, E., Stegeman, A., Loeffen, W.L. Survival of classical swine fever virus at various temperatures in faeces and urine derived from experimentally infected pigs, Vet Microbiol. 2008; 132: 249-59

H.G.P. van Gennip, G.K.W Miedema, R.J.M. Moormann and P.A van Rijn; Functionality of Chimeric E2 Glycoproteins of BVDV and CSFV in Virus Replication. Virology: Research and Treatment 2008:1 29–40

Weesendorp, E., Landman, W.J.M., Stegeman, J.A., Loeffen, W.L.A. Detection and quantification of Classical Swine Fever virus in air samples originating from infected pigs and experimentally produced aerosols. Vet Microbiol. 2008; 127: 50-62.

Dortmans, J.C.F.M., Loeffen, W.L.A., Weerdmeester, K., Poel, W.H.M. van der,  Bruin, M.G.M. de. Efficacy of intradermally administrated E2 subunit vaccines in reducing horizontal transmission of classical swine fever virus. Vaccine 2008; 26: 1235-1242.

Boender, G.J., Nodelijk, G., Hagenaars, T.J., Elbers, A.R.W., De Jong, M.C.M. Mapping of areas at high risk for spread of classical swine fever virus in case of an outbreak in the Netherlands. BMC Vet Res 2008; 4: 9.

Elbers, A.R.W., Gorgievski-Duijvesteijn, M.J., Van der  Velden, P.G., Loeffen, W.L.A. Toepassing van uitsluitdiagnostiek voor klassieke varkenspest bij aspecifieke klinische problemen op varkensbedrijven: een enquête onder varkenshouders en dierenartsen. Tijdschr. Diergeneeskd. 2007;  132: 340-345.

van Rijn, P.A. (2007). A common neutralizing epitope on envelope glycoprotein E2 of different pestiviruses: Implications for improvement of vaccines and diagnostics for Classical swine fever (CSF)? Vet. Microbiol. 125, 150-156.

Engel, B., Bouma, A., Stegeman, A., Buist, W., Elbers, A., Kogut, J., Dopfer, D., Jong, M.C,M, de. When can a veterinarian be expected to detect classical swine fever virus among breeding sows in a herd. Prev. Vet. Med. 2005; 67: 195-212.

H.G.P. van Gennip, A.T. Hesselink, R.J.M Moormann and M.M. Hulst; Dimerisation of Glycoprotein Erns of Classical Swine Fever Virus is not essential for viral replication and infection. Arch Virol. 2005 Nov;150(11):2271-86

H.G.P.van Gennip, A.C. Vlot, M.M. Hulst, A.J. de Smit and R.J.M. Moormann. Determinants of Virulence of Classical Swine Fever Virus strain Brescia. Journal of Virology, August 2004, p. 8812-8823, Vol. 78, No. 16

van Gennip, H.G.P., Bouma, A., van Rijn, P.A., Widjojoatmodjo, M.N., and Moormann, R.J.M. (2002). Experimental non-transmissible marker vaccines for classical swine fever (CSF) by trans-complementation of ERN or E2 of CSFV. Vaccine 20, 1544-1556.

van Gennip, H.G.P., van Rijn, P.A., Widjojoatmodjo, M.N., de Smit, A.J., and Moormann, R.J.M. (2000). Chimeric Classical Swine Fever Viruses Containing Envelope Protein ERN or E2 of Bovine Viral Diarrhea Virus Protect Pigs against Challenge with CSFV and Induce a Distinguishable Antibody Response. Vaccine 19, 447-459.

De Smit AJ, Eblé PL, de Kluijver EP, Bloemraad M, Bouma A. 2000. Laboratory experience during the classical swine fever virus epizootic in the Netherlands in 1997-1998. Vet Microbiol 73(2-3); 197-208.

de Smit, A.J., van Gennip, H.G.P., Miedema, G.K.W., van Rijn, P.A., Terpstra, C., and Moormann, R.J.M. (2000). Recombinant Classical Swine Fever (CSF) Viruses Derived from Chinese Vaccine Strain (C-strain) of CSF Virus Retain their avirulent and immunogenic characteristics. Vaccine 18, 2351-2358.

Widjojoatmodjo, M.N., van Gennip, H,G.P., Bouma, A., van Rijn, P.A., and Moormann, R.J.M. (2000). Classical Swine Fever Virus Erns Deletion Mutants: trans-Complementation and Potential Use as Non-Transmissible Modified Live-Attenuated Marker Vaccines. J. Virol. 74, 2973-2980.

van Rijn, P.A., van Gennip, H.G.P., and Moormann, R.J.M. (1999). An Experimental Marker Vaccine and Accompanying Diagnostic Test both Based on Envelope Glycoprotein E2 of Classical Swine Fever virus (CSFV). Vaccine 17, 433-440.

van Gennip, H.G.P., van Rijn, P.A., Widjojoadmotjo, M.N., and Moormann, R.J.M. (1999). Recovery of Infectious Classical Swine Fever Virus (CSFV) from Full Length Genomic cDNA Clones by a Swine Kidney Cell Line expressing Bacteriophage T7 RNA Polymerase. J. Virol. Methods 78, 117-128.

Rijnbrand, R. van der Straaten, T, van Rijn, P.A., Spaan, W.J.M., and Bredenbeek, P.J. (1997). Internal entry of ribosomes is directed by the 5' noncoding region of classical swine fever virus and is dependent on the presence of an RNA psdeudoknot upstream of the initiation codon. J. Virol. 71, 451-457.