I think poor Ginger and Rackhell are probably most in the firing line, they were the ones Gabriella used as a pacifier
But according to my infectious diseases chart (thanks Ministry of Health

) Hand, Foot and Mouth is only contagious from the time the child actually becomes unwell, so even if Ella is incubating it, she probably couldn't have passed it on.
The snotty noses my gremlins were sporting are a different story, here's hoping they kept those to themselves