Hi CJ,
Hand, Foot and Mouth disease is a pretty nasty thing. The symptoms many only last a few days but it's contagious for WEEKs after. It's a virus and medically there is no way to treat. The natural community uses digestive enzymes because they break through the outer layer of the viral cell and devour the sickness. You can also prevent it with the enzymes....but I think it would probably be hard to get the parents of your kids to jump on that band wagon. I as the owner of the daycare would start on them immediately. I keep Virostop in my cupboard for this type of occasion. It's manufactured by Enzymedica and can be found at health food stores that carry pharmaceutical grade supplements. My husband took it last summer and only got a mild case (6 sores and a little fatigue) of chicken pox.
Your best prevention is to keep that kid out of the daycare for the next month. there may be a medical test to see if it's still contagious or not but I haven't heard of anything like that.
Sorry for the bad news!
M.
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