That sounds like only half the story.
As Foxhunter says, EHV-1 is very prevalent in the horse population. It can manifest with respiratory signs (Rhino), abortions, or neurological signs. There is an indication that a certain point mutation has a higher incidence of causing neurological signs, but other strains can too, I.e. That mutation is not necessarily needed to cause neurol. Signs.
The virus - like Herpes in humans - goes into latency, which means the horse is infected, and then the virus "retreats" into certain cells. In that state, it will most likely be possible to detect antibodies in the horse, but the virus itself cannot be detected. It can resurface, esp in periods of stress (like a cold sore in humans), and the animal can shed again.
Vaccination does not prevent infection or shedding, but only reduces the clinical manifestation of Rhino, and to a debatable degree. Abortions (Pneumabort vaccine).
"Diagnosed with EHV-1" can mean many things. It is very common that horses have antibodies. It is also not uncommon for a horse to shed virus in a stressful situation.
If however a horse already has neurological signs (which I am suspecting was the cade with this mare), the prognosis is poor.
So girl 1, the owner, would very likely only prolong the suffering of the horse by hiding the diagnosis. Not very smart.
Not sure what the rules for reporting EHV in your state are, but chances are that not much would have been done apart from separating / quarantining the horse and good hygiene (i.e. No swapping water buckets etc). As far as I know, you're not actually required to put a neurological horse down.
I know that EHV-1 is scary, but there is not much more to do than keep good hygiene and keep the horses in a good, healthy condition.
The same person (on CL) that had this horse had several others that they gave away for "free". Plus the fact that girl 1 was a irresponsible pet owner and lied to two different vets that she had put the horse down. As well using other horse owners equipment and not letting them know until after the fact.
Those are the things that make me mad about the situation.
What dose that look like? I knew someone who had an appy that looked like he had herpes. He had bloody blisters around and on his 'boy parts' and in/on his mouth. They would pop and bleed everywhere(eww and would freek me out). The lady said the vet said there was nothing they could do, and it was not contagious.
Keiger I'm not sure what your friends horse had but here is what I found on the web about equine herpes
Fever—commonly precedes other clinical signs, but may be the only clinical sign and goes undetected, therefore, temperature monitoring twice a day is suggested.
Respiratory disease Fever
Coughing Nasal discharge
Neonatal foals infected in utero are usually abnormal from birth: Weakness
CNS signs (occasionally)
Death commonly occurs within 3 days.
Older foals: nasal discharge is most common sign of illness.
Usually no warning signs of impending abortion
Typically occurs late pregnancy (8+ months); occasionally as early as 4 months.
Incoordination of the hind (and occasionally fore) limbs
Neurologic signs may be preceded by fever and respiratory signs.
"EHV-3 causes a venereal disease in horses and is transmitted primarily by skin to skin contact. It does NOT affect the respiratory system and is not spread by airborne particles or nasal secretions. It can be transmitted by shared equipment and by people not washing properly after handling an infected horse. If you notice blister type lesions when you are cleaning a colt’s or horse’s sheath, or you notice blisters around the muzzle of a foal, notify your trainer and/or veterinarian. This could indicate EVA infection."
This is kinda what it looked like
This is what I found. SOOO glad I NEVER touched that horse.