Very low chance of transmitting HCV in this fashion, a bit higher for HIV and still higher yet for HBV.
For all these viruses it depends dramatically on the viral load that is present in the inoculum.
For HBV for example, it can be from a a few thousands to 10 billion per ml of plasma. It is obvious therefore that the chance that a transmission occurs in a particular case in itself varies by an incredible factor of one million for HBV.
Thus it would be prudent to obtain not just a simple serological answer re the serological status of the assailants blood, but also, if serologically positive for any of these viruses, but particularly HBV, to determine the viral load present. It is feasable, also, to determine a viral load from the suspects sputum, to give an even better idea for risk estimation.
I assume that you are not vaccinated against Hepatitis B. If so this might be a good time to catch up with that, since violent contacts with infected persons are always a real possibility.
A protective shot with Hepatitis B immunglobulin ( HBIG) would also have been iin order, that would have best protected you against the HBV risk, if not vaccinated.
The combivir contains as one component Lamuvidine, that is both effective against HIV and HBV, but full protection is not assured, since these antivirals only work once the virus has entered the host cell and begins its replicative cycle.They do not protect against primary infection/cell entry as HBIG, a neutralizing antibody does. Nevertheless, it should provide a very substantial reduction of risk.
Not to scare you, but many HIV infected individuals carry the lamivudine resistant strain. A better protective antiviral would have been Tenofovir ( Viread), that also provides potent double protection against both HIV and HBV and carries a very small risk of preexisting resistance against HIV and literally none against HBV.
First, sorry about what you had to go through doing your job protecting us. You should also be aware that most of us here are Hepatitis C patients and not doctors.
That said, I believe Combivir is to help prevent HIV (AIDS) in the event that you were exposed. I do not think it has any effect on Hepatitis C.
Your exposure to Hepatitis C is very low risk but testing is prudent.
Given the suspect's Hep C status, the best person to advise you on further testing (and what to do re the Combivir) would be a liver specialist (hepatologist) and ideally one who works with HIV patients. Hepatologists can usually be found at your larger, teaching hospitals. Of course you will have more information when the HIV tests come in, and I assume they also tested for Hepatitis B?
Again, I don't think you have too much to worry about, but further testing and consultation with a medical expert seems like the right thing to do.
All the best,
-- Jim