Since I seem to be answering the same questions every 15 minutes, I figured I would weigh in with my opinions and insights on the current EHV situation. There seems to be a lot of differing information being distributed and I hope I can pass on what I know and what I have been telling my clients .
As far as the state of things in California, 1 Warmblood that flew to Ontario and shipped to Rancho Santa Fe has died and 1 horse at Bay Meadows Racetrack in San Mateo has tested positive and is being treated at U.C Davis Vet School. The Warmblood is one of the group from Europe that shipped into a quarantine facility in New York State and is part of the group that started the serious condition in Florida. So far, these are the only 2 horses in the state that have shown neurological signs. Two weanlings that flew on the plane to Ontario has tested positive for the respiratory form and shown respiratory signs only. I reported in the Eldorado shipment advisory that they tested positive for the neurological form, but that has been proven to be false information.
I worked for 12 years at Bay Meadows and Golden Gate Fields and have spoken today with my former associates and they say that the horse that was sent to Davis had no connection to the affected Warmblood and had been at the track for some time. This is a little confusing, except that neurological EHV-1 has been a consistent problem at the tracks in the Midwest and East coast for the past 2 years. Possibly a carrier horse may have entered the mix and not shown clinical signs itself. In any case, the tracks are on lockdown and no horses can leave for at least the next 10 days. 21 days seems better to me but we will see.
So what should everyone do? First of all, we should not be waiting for an epidemic as motivation to vaccinate our horses. We should have been doing that all along. That opinion aside, you cannot ignore the science that says even if you give flu/rhino vaccines every 2 months, your horse may not be protected against the neurological strain. I hear all the calls for Rhinomune as the answer to the problem. That comes mainly from a Cornell University study that tested 3 groups of 5 horses. 5 horses received a placebo, 5 received a “killed” vaccine and 5 received a modified “live ” vaccine (Rhinomune). All the horses received a challenge with the neurological strain of EHV-1. In short, the results concluded that the group receiving the modified live vaccine seem to gain more protection against an EHV-1 challenge. This is good news, but it is still only 5 horses in a clinical trial. Does this truly relate to a real life infectious state?
So, since we do not have any sign of an infection here at Eldorado at this point, if your horse are due for vaccination, you might choose to do them now before an infection shows up. If they have been recently vaccinated, good for you. If they have never been vaccinated, then you need to start a 2 or 3 shot series and you better get started. In any case, remember these facts. Your horse may not be protected against the neurological strain no matter what you do. If you vaccinate now, your horse may be even more suceptible to infection in the short term (~2 weeks). Just pray we do not have any horse show up with the disease.
As my last point, please help identify any horse shipping in to Eldorado that may be coming from an infected region. This infection will shut our club down. Thanks.
Mike Manno, DVM, MS