Our hamster is shedding his fur. Do you know why this is happening?

Tweet

Hi MyLotters, My daughter has a hamster which is 4 months old. He has a lot of fur and is like a little teddybear. From about a week ago, we noticed that he is shedding the fur on his neck and back. We don't know why this is happening and all related items on google mention old age which is not the case here. Can someone tell me why this is happening and should we take him to the vet? We're very worried so your help will be much appreciated. Thanks to you all.