Classical swine fever (CSF) is one of the most important viral diseases affecting pigs worldwide. Due to its tremendous socio-economic impact, the disease is notifiable to the World Organization for Animal Health. Within the European Union, prophylactic vaccination is prohibited since 1990, but emergency vaccination is among the legal options. The disease affects only domestic pigs and wild boar.
Classical swine fever is caused by a small enveloped RNA virus of the genus Pestivirus within the Flaviviridae family. Classical swine fever virus is closely related to Bovine viral diarrhea virus (BVDV) and Border disease virus that also belong to the genus Pestivirus. This relation can cause problems in CSF diagnosis due to cross reacting antibodies that may lead to false positive laboratory results.
Depending on host and virus factors (e.g. virulence of the isolate involved) as well as the time point of infection (pre- or post-natal), different disease courses can be distinguished. Beside an acute course, the disease can also manifest itself in chronic or “late onset” disease courses. Especially the latter two can be most problematic for clinical diagnosis as they are associated with unspecific clinical symptoms.
Figures from the disastrous CSF epidemic in The Netherlands 1997/98 may illustrate the impact of CSF. In connection with this epidemic and its 429 outbreaks, 12 million pigs were killed. Direct costs amounted to 2.3 billion Euro.