those are expert's opinions on the matter with quotes to reported cases.
the fact is that oral sex is an extremely low risk activity. but this does not matter when someone has the very bad luck to be the 1 in 10,000 person (or more) to be infected in this way. I personally prefer to recommend people using condoms for oral to reduce the risk to zero, rather than saying that "oral sex is no risk" like unfortunately certain people in some sites (e.g. medhelp.org) irresponsibly do. After all, unprotected oral sex is also an open door to other STIs.
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