Dr Joel Gallant, John Hopkins HIV
About condom protection against HIV
1. An intact condom, properly used, is virtually 100% effective at preventing HIV transmission.
2. You can't get infected through intact skin, so it is not necessary that the entire penis be covered. The skin at the base doesn't matter.
3. If you use condoms all the time, and stop intercourse if the condom ever breaks, then you should be fine
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