I have been exposed to raw sewage in my unit for the past 3 months and more so in the last 7 days.?

Since 22 march this year i have had 6 sewage overflows in my bathroom more recently since 23 june until 27 june 2011. had plumbers and tech officer come to investigate. Problem resolved so they say. but in the meantime i have been tested positive to the hep b virus 28 june. this test was conducted on 31 march 2011. Housing claims flat to be uninhabitable to live in and that it is a health and safety issue, but in trhe meantime i am to continue to live in this flat and the clean up of the exposure in the flat to the sewage overflow has not been addressed by the dept... my health in the meantime has severely been comprised as i am not a well woman. what steps do i need to take to make the housing dept to take this matter seriously and resolve the problem.