Transmission of classical swine fever virus by artificial insemination during the 1997-1998 epidemic in the Netherlands: A descriptive epidemiological study

In the course of the 1997-1998 CSF epidemic in the Netherlands, two semen c ollection centres (SCC) became infected. As an eradication strategy for an acute crisis situation, it was concluded that all semen of the boars at the SCCs collected and distributed in the risk period of 28 January to 7 March 1997 was potentially contaminated (suspect semen). As a consequence, a tot al of 1680 pig herds, mainly located in the southern part of the Netherland s, were officially declared CSF suspect The purpose of this study was to in vestigate whether infection of farms through contaminated semen played a si gnificant role in the CSF epidemic. A total of 123 CSFV infected herds were identified, that had received suspect semen from one or both of the infect ed SCCs, In 87 out of these 123 infected herds, infection by way of artific ial insemination (AI) could be excluded either according to the inseminatio n information or the infection pattern observed. In only 21 herds, infectio n by way of AT was regarded as possible according to the insemination infor mation and infection pattern. Owing to missing information, no conclusion c ould be drawn about the possibility of infection of 15 farms by way of AI, Thus, we conclude that at most 36 farms may have been infected through AI d uring the CSF epidemic in the Netherlands.