A THOUGHT FOR WORLD AIDS DAY

It's World AIDS Day and I have a question. If we're engaging in safe sex to prevent HIV transmission, then why do so many people get tested so often? Doesn't that imply that frequent testers aren't having safe sex? When your last test said negative, wouldn't you want to preserve that negative status? I know that they say testing is important because early detection helps the efficiency of treatment. But if we were actually having safe sex and not transmitting HIV, we wouldn't have any virus that required treatment. Just a thought.