Jackson, Miss., is ground zero in the fight against HIV.

In America’s south, a combination of factors has created the perfect environment for HIV to thrive.

The south has been and continues to be one of HIV’s strongholds. Southern cities in particular are disproportionately affected by the disease, and poor access to comprehensive health care in many southern states is an added hurdle for those who try to get help.

The stigma associated with the disease in some poor, black communities can fuel denial. Many do not believe they are at risk of catching a virus that can affect gay people, even if they are men who sleep with men themselves.

Because they don’t get tested or treated, a virus that modern medicine can effectively tame continues to spread unchecked in some communities.

Jackson, Miss. leads the nation in HIV diagnoses among men ages 13 to 24, according to a report updated last month by the U.S. Centers for Disease Control and Prevention (CDC). Just this week, a black pastor who lost his sister to AIDS became Jackson’s fourth mayor in a year.

Of the 50,000 new HIV infections in the U.S. each year, white men who have sex with men account for the greatest number of cases, at about 11,200. Black men who have sex with men are right behind, at 10,600.

Blacks represent 44 percent of all new HIV infections. In 2009, they also represented 44 percent of all people living with HIV in the U.S., even though African Americans constitute just 12 percent of the U.S. population.

Dr. Leandro Mena serves as medical director of Crossroads Clinic in Jackson, the only publicly funded HIV clinic in all of Mississippi. He also serves as the medical director of a newly opened clinic for gay men and lesbians, also in Jackson.

He told Healthline that nine of the 10 cities in the U.S. with the largest number of new HIV infections annually are in the south. His Jackson clinics see 150 new infections each year, he said.

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But Mississippi is also among the most poorly funded states in the nation in terms of its ability to offer healthcare services to those who cannot afford them. The state opted not to participate in the Medicaid expansion offered under the Affordable Care Act.

In a report issued by the Duke Center for Health Policy and Inequality Research, several scholars make the argument that HIV has reached “crisis proportions” in the south. The report, updated in late 2012, mentions nine states in which poverty, poor overall health, and social stigma keep HIV alive. They are Alabama, Florida, Georgia, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, and eastern Texas.

“Mississippi has the highest disproportionate number of uninsured,” Mena explained, adding that many cannot afford to buy health insurance through the government’s online exchange. “Then there’s the stigma of having HIV, and they don’t want to be seen near a clinic.”

Those who do seek treatment often do so after great delay. Meanwhile, modern antiretroviral therapy, for those who take it faithfully, can reduce a patient’s viral load to undetectable levels. This makes transmitting the virus much less likely, even during unprotected sex.

Amy Nunn is an assistant professor at Brown University school of public health in Providence, R.I . She has done extensive research on the social forces that drive HIV infections.

A firm believer in targeting HIV prevention efforts where they’re needed most, she believes in engaging with people who are the pillars of the affected communities. In densely populated urban areas, she has participated in door-to-door HIV testing efforts.

A native of Little Rock, Ark., her own experiences have bolstered her commitment to the cause. She serves as executive director of Mississippi Faith in Action, a coalition of churches committed to talking about HIV with their congregations.

She points to studies that show that churches tend to be the backbone of many black communities. “If we want to do this in a culturally congruent way, we have to involve community leaders and do this in a way that makes sense to the black community,” she told Healthline.

Pastor James Henley of Fresh Start Christian Church in Jackson told Healthline that discussions about HIV must be had. Period. “Do we really have a choice if we are to save our next generation? A big part of the problem, and nobody will admit it, is that in the African American home this subject is not discussed as much as it should be, if at all,” he said.

He noted that basic knowledge about the science of HIV, including how it is transmitted, is sorely lacking. His church has demonstrated with packing tape how germs can be spread from one person’s arm to another, for example. The analogy is the same for sex with multiple partners. “You have to figure out ways to talk to them in their language,” he said. “You can only work on one child at a time.”

Jackson elected Tony Yarber mayor this week, the Clarion-Ledger reported. Yarber, a pastor, has partnered with Nunn’s group and worked hard to spread the word about HIV testing. He lost his sister and nephew to AIDS, and knows firsthand about the stigma in Jackson. He has spoken about it publicly.

Henley is hopeful. “We took a poll at church, and more guys 18 to 25 showed up and got out to vote than I’ve seen in many years, since the first election of Obama,” he said. “This younger group, they are getting involved in politics and listening. That means many minds are being opened to hear other things, such as behavior modification.”

Phill Wilson, president and chief executive officer of the Black AIDS Institute, said it will take more than just churches to the turn the tide. It will take engaging the black media, civil rights organizations, and fraternities and sororities.

Above all, it will take education, he told Healthline.

“We are shocked that people do not know what we’ve not taught them, and that allows us to blame them,” Wilson said. “We need to aggressively address HIV science literacy.”

It also takes access to healthcare, he said. “We have, unfortunately, a perfect storm, in that region of the country where HIV is most prevalent and people are most in need for accessing healthcare. It also happens to be in the area of the country with the greatest political resistance to getting people access to healthcare,” Wilson said.

Nunn authored a paper published in AIDS Patient Care and STDs that showed that primary care doctors in the Mississippi Delta region tend not to offer HIV tests. They reported that they could not bill insurance for the tests and that there was a stigma surrounding the tests for their patients. They felt HIV testing was the duty of public health departments.