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The disease spreads through the secretions of respiratory, intestinal tract like nasal or throat secretions, stool.
It is also spread through direct contact with blister fluid.
It is most contagious during the first week of the illness.
He should be out of your care till the fever subsides or till the blisters, if there is any are healed.
The usual period for the symptoms to arise is 3-6 days after initial contact.
So by this period her sister may develop the symptoms.
If she has any symptom she should also avoid coming.
Frequent hand washing should be practiced.
It is particularly important after using toilet & before taking meals.
The toys should be cleaned with a disinfectant.
Virus can stay there for a few days.
I hope this information will be helpful.
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