From WebMD (
http://www.webmd.com/lung/understanding-pneumonia-basics):
"Many of these germs are all around us. They usually can't get past a healthy person's natural defenses. Pneumonia is most common in those with weaker or compromised immune systems, elderly people, cigarette smokers, alcoholics, and people suffering from other diseases such as the flu."
You should be fine, and it's a bit much to expect the parents at either of your two jobs to be worried about both your health and the health of the other child. If you won't work with actively sick children, and you care for two babies, you're going to be very unpredictable ...