1. Kiddie pools. I mean the one foot deep cess pools you often find alongside a real human sized pool. WHY!!! It's not like you can leave your kid in it unattended. So you stand there either hot or freezing, swimsuit clad body exposed, in a body of water that likely doesn't offer a large enough dilution factor for the amount of human waste it holds. They suck. Just hold and play with your kid in the real pool. (This does not apply to plastic backyard swimming pools).
2. Pink eye. It is so common and honestly not that big of deal. But parents need to run meetings, interact with bank tellers and do other tasks that would be easier if you didn't look like death.
3. Lice. See #2 above but add an extra layer of panic and disgust.
4. Chuck e cheese. Not really. I love the chuckster!