A question has been raised whether the increased number of West Nile virus (WNV) cases in Kentucky in late summer and fall 2002 contributed to a rise in fall abortions. A retrospective study by the University of Kentucky’s Livestock Disease and Diagnostic Center (LDDC), from July of 2002 through early 2003, looked at 400 equine abortions for evidence of WNV. Their findings were “surprising,” said LDDC head Lenn Harrison, VMD. Of the 400 examined, 35 (about 8.8%) had evidence of WNV identified on polymerase chain reaction testing. This is the same test the laboratory uses to check for WNV in birds.

West Nile virus has not previously been associated with abortion, and researchers are not saying that is the case now. They have no evidence at this time that WNV caused the abortions; they are only saying that there was evidence of the virus in the aborted fetuses. The virus has not been isolated in the fetuses at this time.

Further testing and information gathering is ongoing to determine the relationship between WNV and abortion