We feel confident that there won't be an outbreak. The people who were around the patient are now being identified and traced by the CDC and by the state health authorities. ... you get people, you identify them, and you observe and monitor them daily to determine if they develop symptoms If they do, then you put them under isolation to determine if, in fact, they are infected. And if you do that properly, you can shut down any outbreak.

You can have an epidemic in a state. You can have it in a region. You can have it in a country where the critical level of disease passes a certain threshold and we call that an epidemic threshold.

The nature of a protective immune response to HIV is still unclear. Because in a very, very unique manner, unlike virtually any other microbe with which we're familiar, the HIV virus has evolved in a way that the immune system finds it very difficult, if not impossible, to deal with the virus.

You help someone's health, and you prevent them from infecting others.

Activism has been very productive in our society.

Previous efforts to eradicate malaria failed for several reasons, including political instability and technical challenges in delivering resources, especially in certain countries in Africa.

When you put someone on therapy, you lower the level of virus such that it makes it very difficult for them to infect others.