02094nas a2200241   4500000000100000000000100001008004100002260007000043653001300113653001700126653002000143653000800163653001900171100001300190700001200203700001500215700001600230245021600246300001200462490000800474520135600482022001401838       2014                            d  c05/2014bSchlütersche Verlagsgesellschaft mbH & Co. KGaHannover10aserology10aSurveillance10aearly detection10aBTV10abulk tank milk1 aM Büchi1 aC Abril1 aA Vögtlin1 aH Schwermer00aPrevalence of antibodies against bluetongue virus serotype 8 in bulk-tank milk samples from dairy cattle herds located in risk areas for bluetongue virus transmission after a vaccination programme in Switzerland  a158-1620 v1273 aSwitzerland had been affected by the bluetongue virus serotype 8 (BTV-8) epidemic in Europe in the years 2007 to 2009. After three years of mandatory vaccination and comprehensive surveillance, Switzerland showed to be free of BTV-8 in 2012. In the future Elisa testing of bulk-tank milk (BTM) samples as a very sensitive and cost-effective method should be used for the surveillance of all serotypes of BTV. To determine the prevalence of seropositive herds, BTM from 240 cattle herds was sampled in July 2012. The results showed an apparent seroprevalence of 98.7% in the investigated dairy herds. Most plausible, the high prevalence was caused by the vaccination campaigns rather than by infections with BTV-8. In the outbreak the cumulative number of BTV-8 cases in Switzerland had been 75. Thus it is very likely that the used inactivated vaccines induced long-term antibody titres. Due to the high seroprevalence, investigating for BT-antibodies cannot be used for early recognition of a new introduction of BTV at the moment. Nonetheless, testing of BTM samples is appropriate for an annual evaluation of the seroprevalence and especially as an instrument for early recognition for incursions as soon as the antibody prevalence declines. To determine this decline the BTM testing scheme should be conducted each year as described in this work.   a0005-9366