"The good news about Pythium is that if you can debunk/remove the lesions, the horses do fairly well," Logas says.
To a certain degree, it depends on the location of the lesion. Those that are most worrisome are those that are on young foals,
or on the limbs, which tend to invade deeper into other tissues. The result often translates into bone involvement along with
"The biggest problem we have is that Pythium is not really a true fungus or a bacteria, but an oomyces, a 'quasi-fungal' organism, and therefore classical antifungal
drugs have not been effective in horses, with only mild success in dogs," Logas says. "For horses, though, the vaccine seems
In horses with small lesions, pythiosis has been found to regress on its own, so whether it is the vaccine or the natural
progression in certain animals is still open to question.
"It's probably going to be more effective in horses, than it is in dogs," she says. "But horses are usually able to mount
a decent response anyway."