Which can reduce the likelihood of hiv infection but is not 100% effective?

post-exposure prophylaxis. PEP for short. It involves taking medicine after contact with HIV.  

Treatment must begin within 72 hours. PEP is only available from a healthcare provider, emergency room, urgent care clinic, or HIV clinic.  

It is not 100% effective. And follow-up  

HIV testing is required

nope, but i have cleaned my brush in my cup of not as potentially harmful but nevertheless, very upsetting for scottish/british folks. especially if you've used the last teabag for it

explanation:

there could be something in that . . i am indeed an old scottish man!

there's a bit of bolshie-ness with it too though. i won't let go of the old ways . . tea and whisky . . whether the young whippersnappers like it or not!