I wish reporting like this, and research behind it, gave more consideration to the animals' living conditions. The article mentions that large cats were kept s

I wish reporting like this, and research behind it, gave more consideration to the animals' living conditions. The article mentions that large cats were kept separate in 30'x40' (around 10m by 12m) enclosures. They eat whatever the zoo provides, meaning the animals don't have free choice as they would in the wild. Everyone I've met over the years who work at zoos absolutely love the animals and care deeply about the job. They would notice any visible or behavioral indicators of stress. That said, though, those conditions aren't natural. It could simply be that germ theory is correct and the animals were perfectly healthy until the pathogen was introduced. Its also possible, though, that keeping wild animals isolated in confined pens isn't a good situation regardless of husbandry practices.