I just wanted to bump this thread to the top as I found it when doing a search on slap cheek when my son came home from school with it. I'm not pregnant but I realise how many pregnant women haven't even heard of slap cheek so thought the issue should be raised again.

As soon as I realised my son had it I rang the school and told them as we have a pregnant teacher. The main problem with slap cheek is that you don't know you have it untill the rash appears on the cheeks, and you are also only infectious untill that stage, so it has pretty much been spread around before you have even found out you have it. It is spread by respiratory droplets (coughing).

So any teachers or childcare workers really need to get checked for immunity to the virus as soon as they find out they are pregnant (not waiting for an outbreak) so they can be more cautious on the job.