An outbreak of equine herpesvirus type 1 (EHV-1) neurological disease (also known as equine herpes myeloencephalopathy (EHM)) is underway in a currently undisclosed location in New Zealand. It appears that at least 12 horses have been affected with 6 deaths, all on one farm.
This is being described as the first outbreak of the neurological form of EHV-1 in New Zealand. That’s pretty surprising to me, since this virus in endemic in the horse population throughout the world, and although the neurological form of disease is sporadic it’s certainly not a rare occurrence. I imagine there have been periodic cases and maybe small clusters, but perhaps they mean that this is the first large outbreak to be identified (but that’s a guess). We do seem to be seeing more large EHV-1 neurological outbreaks in recent years, and I don’t think it’s just because we’re recognizing them more.
Fortunately, there is now much more willingness amongst most sectors of the equine industry to take these outbreaks seriously and act much more quickly and comprehensively than in the past (when getting people to admit to an outbreak was a challenge, let alone getting any action).
Hopefully this one’s been contained on the farm and no further spread will be encountered.
Stay tuned for the launch of WormsAndGermsMap, a real-time disease mapping site to track cases like this. Coming soon.