If your baby has a fever and develops a rash, it is important to monitor their overall condition. You can apply a fragrance-free moisturizing cream as needed during the day and give them acetaminophen for pain relief if necessary. If the rash persists for more than a week or gets worse, it is best to consult a doctor. Pregnant women should avoid close contact with anyone who may have a contagious condition and should practice good hand hygiene to prevent infection. It's always best to seek medical advice if you have any concerns about your baby's health.