Hi,

Well both ways you can do your PhD. If you pursue microbiology through medicine then you will first have to do mbbs and then select md in microbiology. Otherwise you can do bsc and then mac in microbiology followed by PhD. Job opportunities are different. Through medicine path, you can become a professor in medical colleges and also appointed as a microbiologist in hospitals and clinics. Otherwise you become a researcher in other fields.

I hope this helps.

All the best.