Share knowledge. Take action. That’s the theme of this year’s National Women and Girls HIV/AIDS Awareness Day, which the nation and the U.S. Department of Health and Human Services’ (HHS) Office on Women’s Health will observe on March 10.

Why should you share knowledge in your community? Because knowledge leads to action.

Here are four things we know about how HIV/AIDS affects women, and the actions that are following from that knowledge:

1. More than 50,000 adults and adolescents in the United States were diagnosed with HIV infection in 2011. One in five was female.We are encouraged to speak directly to women about ways to protect themselves. We are also encouraged to create systems of care that consider the specific situations and needs of women diagnosed with HIV/AIDS.

2. Eighty-six percent of women and adolescent girls (ages 13 and older) newly diagnosed with HIV infection got it by having unprotected heterosexual sex. The rest were infected by injection drug use.We know that helping teens and women avoid risky sex and injection drugs will also help prevent HIV/AIDS.

3. Women of color account for two-thirds of new AIDS diagnoses among all women in 2011. At some point in their lifetimes, 1 in 32 black women and 1 in 106 Hispanic/Latina women will be diagnosed with HIV. (For white women, 1 in 526 will be diagnosed in their lifetimes.)We are aware that we need to work hard to get information into the hands of women of color.

4. Five things put women at greater risk for HIV: unprotected sex, sexual abuse, other sexually transmitted infections, a lack of proper health care, and substance abuse (e.g., injection drug use).Knowing the risk factors reminds us that HIV/AIDS is preventable, and encourages us to collaborate with others who are working with women to reduce their risk.

I hope you’ll join me on March 10, and throughout the month, in sharing knowledge about HIV/AIDS, sharing the stories of survivors and those we’ve lost to the disease, and taking decisive action to realize the dream of an AIDS-free generation.

At the Centers for Disease Control and Prevention (CDC) and other HHS agencies, efforts are underway to develop and study interventions that help prevent HIV/AIDS among women and adolescent girls. And both the Affordable Care Act and the National HIV/AIDS Strategy are increasing access to testing, prevention, treatment, and care. This October, women can begin using the Health Insurance Marketplace, which is designed to help people find health insurance that fits their budget. To learn more about the Marketplace, visit signup.healthcare.gov.

With these initiatives, and the hard work of people like you in communities across the nation, it is my hope that soon we will all tell a different story of improved awareness, fewer HIV infections, and equal access to quality health care.

Are you sharing knowledge about HIV/AIDS? Is your community educating and empowering women and girls to reduce their risk of infection? For resources and tools, visit the National Women and Girls HIV/AIDS Awareness Day website. Also, visit Act Against AIDS for information about HIV/AIDS from CDC—now available in English and Spanish. Act Against AIDS is a five-year initiative launched by CDC and the White House in 2009 to fight complacency about HIV in the United States. Act Against AIDS includes a number of campaigns, ranging from national awareness campaigns to more targeted campaigns for high-risk populations, like Take Charge. Take the Test., a campaign that encourages African American women to get tested for HIV.