If a brain is swollen, is it considered an injury/damage?

Mostly, people who get into accidents like car accidents end up with a severe brain injury/damage but in my brother's case, he didn't get into an accident or any of that. He "fainted" all of us sudden and was discovered that he got a virus in his brain, which I don't know the cause yet. It was found out that his brain was "swollen" and filled with "water". Doctors purposely put his brain to sleep (it's been a week so far) so it can heal/recover and I want to know if this is a serious injury/damage or a minor one. Do most people heal/recover successfully from an induced coma? Will my brother restore normally?