They do not own the blood, but the manufacture of blood products. Its still a bad idea though, as these things become private all accountability and transparency disappear except what little is mandated under law. For companies supplying essential services this is an issue. However the same could probably be said for many companies, I do not know that this case is unique.
The other issue is that state developed and owned industries supply revenue to the state. Sell it for fast bucks and you lose a continuing income stream. Its selling off the assets for cash without reinvesting. I understand their need for paying off government debt, but I do not know what kind of returns the government was getting here. Maybe it was dismal. Maybe it was a lot. Maybe they made cheaper product which reduced the costs associated with govt. hospitals and services. Its not a clear issue, but it is a worrying issue if this information was not public.