A Serum Neutralization test detects antibodies but cannot distinguish a vaccinated animal from a previously infected animal. Since the disease is endemic in the equine population, a low SN should not preclude travel.
Yes, it’s among the rule-outs listed in the presentation.
Yes, providing adequate distance (30 ft) while considering prevailing wind direction.
Microchip temperature monitoring chips may not match a horse’s rectal temperature exactly. However, they are reliable for tracking temperature changes when compared to that horse’s own baseline. The key is consistency—use either the microchip or a rectal thermometer, but not both, so you can accurately monitor trends over time.
Most common disinfectants are effective against EHV because it is an enveloped virus and is therefore relatively susceptible to disinfection. Standard quaternary ammonium compounds are effective, and bleach can also inactivate the virus.
That said, the biggest challenge is not the disinfectant itself—it’s making sure surfaces are thoroughly cleaned before disinfection. Organic material can reduce the effectiveness of many disinfectants. This is especially important in barns or stalls with wood surfaces. For those areas, it’s best to use disinfectants that are not easily inactivated by organic matter. For that reason, bleach would not be my first choice for use on wood surfaces.
It is the prerogative of an event to require a 30-day CVI, specific vaccinations, or other requirements. An EECVI trip permit provides much improved traceability over a 30-day CVI, which is why either an EECVI or a similar tool has been allowed by state animal health officials for equine movements in the Northwest and Southeast for many years.
SAA is a good marker for inflammation associated with rhinomneumonitis EHV. However (according to an equine internist at Michigan State University), SAA is not of much help for EHM as the inflammation is localized, and the signs of EMH (especially as they progress) are due to infarcts rather than inflammation. The half-life of SAA is 12-24 hrs, so it is fairly responsive to more general inflammatory status.
Generally, cold temperatures like 9°F (assuming you’re on the Fahrenheit scale) will not negatively affect virus survivability and, in fact, may help preserve the virus. Heat, drying, and UV light (sunlight or other sources) will naturally inactivate it.
USEF requires it within 6 months, and I recommend the vaccine be given as close to the 6-month interval as possible. The study cited below suggested that, “..in addition to sex and biosecurity risks, factors associated with higher EHM risk included EHV-1 vaccination in the 5 weeks before the event.”
EHV Study