What temperature is counted fever for infants? My baby is 2 months old. She is having a temperature of 37.8 What do i do?

37.5 is consider fever. 37.3 is consider low grade fever as described by our doctor. 37.5 should head to the doctor. And usually fever occurs is due to viral infection. Fever is a symptom of something else. It's not an illness by itself. And given baby is just 2 mths old, need to bring to pd or hospital A&E. -we just came back from A&E 2weeks back. Dr said if fever starts need to head straight back. My baby is 2 mths+ too. Elder child passed bronchilitis to the younger one for a mth b4 we decided to head to A&E. Which means the younger one caught it at 1mth old. :(