I personally dont use it as I have my own system of spam control these days - but they do offer Spam Assassin & Clam AV.
Bit hard to remember from my old package when I had it turned on.. but it does mark spam and possible virus files in the header.
These are some of the options from their C-Panel for mail (screen shots below)
PS cheeky I know... but if you are going with them,
would you go through this linky:- Vidahost
as the site may get a couple of quid.
Im not recommending them for the £ -
I recommend them because I am very happy with them... and they are far
better than any other hosting service I have used over the past 10 yrs or so.