"People who test positive for the hepatitis B virus for more than six months (after their first blood test result) are diagnosed as having a chronic infection. This means their immune system was not able to get rid of the hepatitis B virus and it still remains in their blood and liver."
Why should the hepatitis B infection last more than six months to be regarded as chronic? My only guess is that, based on stasticial studies, more than half of the patients that got the infection for more than six months could not ever get rid of it.
Is this right? Is there some explaination to what is progressing in these six months, that led to this? Is this a concept common in other diseases?
Why is it 6 not 8 or 4?