Sad and puzzling indeed.
I looked up hendra with the cdc here's the link:
http://www.cdc.gov/ncidod/dvrd/spb/m...ages/nipah.htm
One of the three Hendra virus infections was marked by a delayed onset of progressive encephalitis. Serious nervous disease with Nipah virus encephalitis has been marked by some sequelae, such as persistent convulsions and personality changes.
So it seems that it really was the right thing to do, particularly as it is zoonotic and is transmitted through secretions, very hard to control.
Kind of sounds a bit like distemper, although different infectious disease. But I took in a litter of rescue pups that ultimately displayed distemper, never again took any animals from that shelter.
One pup never got sick or displayed any kind of symptoms, but a few weeks later began having seizures. After talking with the vets, while they may recover at best they are neurologically impaired for the rest of their lives, and they really couldn't say wether or not they may be carries. So althugh she seemed perfectly healthy except the seizures I had to put her down. This was my first and hopefully last experience with distemper.
Actually it was a nightmare for me as I had to nolvasan my entire garage and surrounding area. Thankfully I am not one that takes in rescues and lets them interact with others, I am one of the few that strictly quarantine, even going to the extreme of changing shoes and clothes. But I did have another litter of Dogo Mastiffs at the time that were very far away from the rescue litter and then had to revaccinate even all my adult dogs.
Really sad though for the owner that fought so hard, I can truthfully say I know the feeling.