Neena Smith-Bankhead remembers the story well.

Several years ago, she watched a person walk into an AID Atlanta HIV testing event with absolutely no clue.

"The person was totally unaware, totally oblivious about the disease and that they could have it," said Smith-Bankhead, director of education and volunteer services at AID Atlanta, one of the largest AIDS service organizations in the Southeast. "Unfortunately [they] found out they were HIV positive."

Which, in a way, made it a good day.

Smith-Bankhead said the person is still alive and has received support and medical care. Most importantly, that line of the disease stopped there.

Smith-Bankhead said the person is still alive and has received support and medical care. Most importantly, that line of the disease stopped there.

"The biggest concern is if this person had not been tested and had infected someone else," Smith-Bankhead said. "We really want to encourage people to know."

Today, the city of Atlanta will try to do its part. In anticipation of Sunday's National HIV Testing Day, Atlanta Mayor Kasim Reed will host a testing day event at City Hall.

Along with AID Atlanta, representatives from the Centers for Disease Control and Prevention, the Black Leadership Commission on AIDS of Metro Atlanta and several local churches will attend to encourage testing.

Reed said private rooms throughout City Hall will be available for counseling and testing, which will be provided by National AIDS Education & Services for Minorities (NAESM).

They will use a rapid HIV test that can provide results within 20 minutes.

"We want everybody to know that HIV testing calls us all to action," said Robert Bailey, team leader for the CDC's National HIV Prevention Partnerships. "HIV testing is key to ending the U.S. epidemic."

Bailey said that nationally, more than 1 million people are living with HIV and 20 percent of them don't know it. He said that between 54 and 70 percent of all new cases are transmitted from people who do not know they are positive.

"That is why prevention is essential in preventing the spread of the disease," Bailey said. "Doesn't matter if one person or a million show up. We are going to continue to drive home the point that HIV testing is key to ending the epidemic."

In Georgia and Atlanta, that is crucial.

According to data compiled by the state in its Comprehensive HIV Prevention Plan: 2009-2013, the cumulative number of AIDS cases reported at the end of 2006 was 31,557.

That is the eighth highest rate in the nation.

Blacks represent the biggest group impacted.

While they make up only 30 percent of the state's population, blacks represented 70 percent of all new AIDS cases in 2006.

"Typically, we know that that is primarily because of the lack of information on HIV due to the stigma and [lack of] access to care," Smith-Bankhead said.

Also, between 1986 and 2006, the rate of new cases among black women rose from 6 percent to 28 percent, making them the most disproportionately affected by the disease.

Smith-Bankhead said that trend is rising because of the rise of risky behavior among black women, who deal with men who may have multiple sex partners.

"I am always leery about having a conversation that blames the plight of black women on black men," Smith-Bankhead said. "We all have a personal responsibility for our health."

Fulton County, followed by DeKalb and Clayton have the highest rates of HIV infection and AIDS cases in the state. Earlier this year, Georgia received $65.6 million in federal Ryan White HIV/AIDS Program funds to use for people with the disease who have no health insurance. Fulton County received $20.3 million of that to use across the region to pay for medications, transportation for medical visits, food and mental health services, and provide primary care in clinics.

The city's HIV Testing Day will begin at 11 a.m. today with a press conference, followed by testing from 11:30 a.m. until 2 p.m.

To find out other locations were HIV tests are conducted, call 1-800-CDC-INFO.