A TELEPHONE-BASED CASE CONTROL STUDY OF FATAL EQUINE COLICS IN WALES DURING 1988 WITH PARTICULAR REFERENCE TO GRASS DISEASE

The present study was designed to evaluate a telephone survey in collecting epidemiological information. Of particular interest was the possible association between grass disease and scrapie. We have carried out a case-control study of fatal equine colic cases seen by veterinary practitioners in Wales in 1988, looking at the exposure of these cases to scrapie-infected sheep. The results indicate that this type of survey is of value where the information required is limited and where recall is likely to be good. The response rate was 95% and the material cost was comparable with that of a postal survey. A total of 1331 cases of colic were reported and 93 (7%) of these were fatal. Seventeen cases of grass disease (1.3%) were reported, but only 41% were confirmed histologically. Scrapie was reported on only two of the premises where fatal colics occurred. There was no association with grass disease at the 5% level, but in view of the fact that the results approached significance (P = 0.06), we suggest that this hypothesis warrants further investigation.