About 27,000 women and girls in the U.S. are HIV-positive and don't know they have the disease. The Office on Women's Health coordinates National Women and Girls HIV/AIDS Awareness Day (NWGHAAD) to raise awareness about how HIV/AIDS impacts women and girls. It takes place each year on March 10 and empowers people to share knowledge and take action. Joining us this year is NWGHAAD Ambassador Tamika Williams. Tamika is a former professional basketball player who is passionate about educating women and girls about HIV/AIDS.

Read her interview to learn why she became an HIV/AIDS advocate and what steps you can take to protect yourself and others.

Q: Tell us why you wanted to be an ambassador for NWGHAAD.

A: HIV/AIDS is a serious issue, and as an ambassador I want to help people understand just how serious it is. I want to do my part to help get the word out and get people talking about the impact this disease has on women and girls in this country, especially African-American women. We're disproportionately affected by HIV infection compared with women of other races and ethnicities. By the end of 2010, African-American women accounted for nearly 64 percent of all estimated new HIV infections among women. I also wanted to get involved with National Women and Girls HIV/AIDS Awareness Day because HIV/AIDS is a personal issue for me. I hope that by sharing information, we'll not only educate people, but we'll save lives.

Q: What are your first-hand experiences with HIV/AIDS?

A: Two years ago, I had the opportunity to travel to Senegal, Tanzania, South Africa, Malawi, and Nigeria to see how HIV/AIDS was affecting these countries. It was an incredibly humbling experience. Then, when I came home, my aunt passed away from AIDS and cancer. These experiences made it a real issue for me and they're part of my personal story.

Q: HIV/AIDS is preventable. How can we help teach women and girls how to protect themselves?

A: First of all, I think we have to promote abstinence, especially among young people, because it's the best way to prevent the spread of HIV. But if you are in a relationship and you're having sex, be faithful to your partner. You should both get tested. It's important to know your status and the status of your partner because most women get HIV from having sex with a man who is HIV-positive. You can't tell by looking at someone whether or not they have HIV, so make sure you know your partner's status. Also, be safe and use condoms. Getting tested for other sexually transmitted diseases is also smart. If you have another STI, it may be easier for you to get HIV if you're exposed.

Q: Why is it important for women and girls to know their status?

A: If you are HIV-positive and you don't know it, you risk spreading it to other people. The only way to know your status is to get tested. Also, early detection is key. Treatments for HIV are better than ever. People with HIV are living longer with a better quality of life. If you are HIV-positive, it's best to start treatment as soon as possible. With the right treatments, HIV-positive people can live for many years without developing AIDS.

Q: What do you think women and girls may not know about HIV/AIDS that they should know?

A: Most importantly, I think women need to know that they have to be responsible for protecting themselves. You're in control of your body. It's okay for you to say "no." It's okay for you to ask your partner to wear protection. It's okay for you to ask questions. If you're having sex, it's crucial you get tested and know your status.

Q: The stigma surrounding HIV/AIDS still exists. Why is it important to reduce this stigma?

A: I think if we reduce the stigma, more and more people will take steps to protect themselves from HIV. Right now, I think people believe getting infected with HIV could never happen to them, but HIV affects people of all ages and races. By reducing the stigma, we accept that truth and take steps to protect our health. I also think reducing the stigma will encourage more people to get tested so they know their status. If they are negative, they need to do everything they can to remain that way. If they are positive, they should not be afraid to get treatment immediately.