Snails immune?

[teff]

After having fed my snails (nerite, marissa, apple, mbt) fish carrion that turned out to be infected with tiny squirmy things inside their bellies, and the snails just keep growing and prospering, is it logical to conclude that snails are immune to parasites?

[pbgroupie]

Not immune as they serve as a host to a lifestage of rat lung worm.

[teff]

Host as a healthy host or sick host?

[pbgroupie]

Host period. They show no signs of the illness itself but if they are sick it would be from something else.