needle stick infection/transmission pathway

Whenever the subject comes up (needle sticks & odds of being infected), I never read anything specific about the kind of needle involved... and I'm trying to get a better understanding of how sticking yourself after giving a subQ injection can get you infected (w/Hep, HIV, etc.).

I can understand butterfly needles from a blood draw but I'm unclear about how a needle used for a subQ or subdermal injection transmits a blood born pathogen. Any good sources I can check out (besides CDC?)

Thanks
I frequently see a drop of blood appear after giving a SQ injection, especially heparin or lovenox...even insulin. Small capillaries are just below the epidermis. Report all needle sticks and receive follow-up monitoring.

Any pointy thing that breaches one of your protective barriers is an 'exposure' and should be treated as such... even if you barely scrape your hand on the patient's surgical staple. Report ALL exposures and work-related injuries, even if it appears that there wasn't any real damage/exposure. There may a period of latency before the damage shows up - if you didn't report at the time, you may not have much financial protection.

Don't forget that exposure can also come from droplets. Either from needles, procedures, or in my case, a patient who was bleeding out of his trach coughed and some of it got in my eye. I walked into that situation when another nurse was calling for help, and had put on all by the eye protection. The patient and I had to go for testing but we were both fine, thank goodness!