Firstly, give only breastfeeds at a gap of at least 3 hours, nothing else by mouth and maintain strict hygiene. Stop bottle feeds if given,in case of top feeds,use a spoon and katori instead of bottle. Add enterogermina vials half vial twice a day for 5 days. If not improving OR accompanied by other symptoms like vomiting or dullness and refusal to feed consult your paediatrician asap.