C had HF&M when he was about 11mths old.
It's is my understanding you can't contract the virus from direct contact with the spots. It's mode of transmission is droplet form i.e from coughing and sneezing which you then inhale and also saliva which is why it spreads like wildfire through daycare centres where babies and toddlers are mouthing toys and they are not washed in between children.
The virus is also present in faeces (and can continue to be for many weeks after the spots have cleared) so can be contracted that way too so make sure you wash your hands really well after nappy changes.
Having said all that it is very uncommon for adults to contract the virus.
Breastfeeding is perfectly fine and often the only thing they will take as their mouth hurts too much to eat

Hope he gets better soon.