Epidemiologic characteristics of bluetongue virus serotype 8 laboratory-confirmed outbreaks in The Netherlands in 2007 and a comparison with the situation in 2006

• Published in: Preventive veterinary medicine Vol. 92; no. 1; pp. 1 - 8
• Main Authors: Elbers, Armin R.W., van der Spek, Arco N., van Rijn, Piet A.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.11.2009; Amsterdam; New York: Elsevier
• Subjects: abortion; Abortion, Veterinary; animal fertility; Animals; belgium; bluetongue; Bluetongue - epidemiology; Bluetongue - mortality; Bluetongue - virology; Bluetongue serotype 8; Bluetongue virus; Bluetongue virus - classification; calves; Case fatality; Cattle; cattle diseases; Cattle Diseases - epidemiology; Cattle Diseases - mortality; Cattle Diseases - virology; cows; disease outbreaks; Disease Outbreaks - veterinary; epidemiological studies; Fertility problems; field observations; infection; lameness; milk yield; Morbidity and mortality incidence rate; mortality; Netherlands - epidemiology; Reproduction; Sheep; sheep diseases; Time Factors; transmission; Netherlands; Bluetongue serotype 8; Case fatality; Morbidity and mortality incidence rate; Fertility problems
• ISSN: 0167-5877; 1873-1716
• DOI: 10.1016/j.prevetmed.2009.08.007

A major epidemic of bluetongue virus serotype 8 (BTV-8) occurred in Western Europe in 2006. During 2007 it became evident that BTV-8 had survived the winter and a re-emerging epidemic quickly developed. The objective of this study was to describe the severity and clinical impact of the BTV-8 epidemic in 2007 in The Netherlands in laboratory-confirmed outbreaks and to compare this with the situation in 2006. The relative frequency of clinical signs in BTV-8 affected sheep flocks and cattle herds in 2007 and 2006 was similar. The most prominent changes were a higher proportion of sheep flocks with lameness and a much higher proportion of cattle herds reporting a decrease in milk yield in 2007. BTV-8 associated morbidity and mortality incidence rates in sheep flocks and cattle herds were significantly ( P < 0.001) higher in 2007 than in 2006. Both in sheep flocks and cattle herds, BTV-8 associated case fatality was significantly ( P < 0.001) lower in 2007, which was probably due to better medical treatment of sick animals. There were significantly ( P < 0.001) more fertility problems associated with BTV-8 infection in outbreak cattle herds in 2007 compared to 2006.