And ruin your rep if anyone does catch anything, just take the time off, its extremely careless to work knowing your infectious

Check out 'Molluscum Contagiosum' virus, also known as 'water warts'.  Not a STI as such, it's very common for kids to get it on their tummies, etc, and seems to affect people with a low immune system, however, it CAN be passed on sexually.

It doesn't cause much bother other than the fact that it looks unsightly and can be a bugger to get rid of (quickly), though should clear up on its own, if you're prepared to wait months!  Not practical in our line of work.