Eight Strategies to Trim Transmission Risk in People With HIV

"Drinking the Kool-Aid" on Treatment as Prevention

Long before HPTN 052 confirmed that antiretrovirals taper HIV transmission rates, the CDC cautioned that undetectable virus in plasma does not necessarily mean virus-free semen, rectal secretions, or genital or pharyngeal fluids.^3,14,15 And an unreadable load in plasma depends on steady adherence and staying free of other sexually transmitted infections. Even certain vaccinations can hike viral load. On top of that, some studies show that doing well on antiretroviral therapy can make people reckless in bed. So even universal treatment of diagnosed people will not tamp down their transmission risk completely.

But it's a big step in that direction. Of the 18 top HIV physicians who responded to RITA!'s survey on positive prevention (see box), 16 listed reining in HIV with antiretrovirals as a prime strategy, and 7 of those 16 cited HPTN 052.¹³

"The single most important thing clinicians can do to prevent transmission is to treat their HIV-positive patients with antiretroviral therapy, our most effective form of prevention," wrote Joel Gallant (Johns Hopkins University). "That doesn't mean that other forms of prevention don't matter anymore," he added. "It's still important to talk about behavior change and condom use, for example. But if every HIV-positive person had an undetectable viral load, the epidemic would be over."

David Wohl (University of North Carolina) seconded that opinion, noting that HIV incidence in HPTN 052 "was pretty low in the control group not treated with antiretrovirals." That means the "prevention measures in the control [arm] -- pretty standard stuff -- seemed to have an effect. That said, I have really drunk the Kool-Aid when it comes to use of antiretrovirals to prevent transmission."

Others believe HPTN 052 opens an avenue to discussing positive prevention with their patients. "I've been pleasantly surprised how the 'treatment-as-prevention' message from 052 has facilitated discussion about prevention in clinical practice, and how motivating prevention can be for people considering starting therapy," said Paul Sax (Harvard Medical School).

Steven Deeks (University of California, San Francisco) agreed, noting that "in my recent experience, this public health aspect of treatment has been a great motivator for some individuals to seek care and begin therapy, so I am optimistic transmission rates will decline."

Some HIV-positive people who may not want to start treatment for their own health "will opt for treatment to prevent transmission," Ian Frank (University of Pennsylvania) is finding. As a corollary to this emerging attitude, Frank suggested, treatment as prevention "can be particularly motivational for people in discordant couple relationships" and for another patient subset -- HIV-positive people looking for a partner but assuming no HIV-negative person would consider a relationship. Now, Frank noted, a positive person with well-controlled infection can tell a potential partner, "I have a low risk for transmission of my infection because my viral load is undetectable," and that "can change someone's outlook" on finding a partner.

Risk Screening and STI Testing for Positive Prevention

Besides treating people to make their viral load too low to tote, what else should HIV providers do to help patients avoid dispatching their virus to others? HIV Medicine Association (HIVMA) primary care guidelines prescribe four essentials:16

1. Screen people for high-risk behavior at each visit.
2. Ask patients about sexually transmitted infection (STI)-related symptoms at each visit.
3. Give a general message about risk reduction at each visit.
4. Tailor messages for patients who report high-risk behavior.

Do providers have to keep hammering on prevention at every visit? The CDC thinks so. "Clinicians should recognize that [HIV transmission] risk is not static," the 2003 guidelines state.³ "Patients' lives and circumstances change, and a patient's risk of transmitting HIV may change from one medical encounter to another."

The HIVMA guidelines, freely available online, 16 boast an ample section on risk screening in people with HIV, including a list of questions most clinicians should feel comfortable asking (Table 3 in Reference 16). HIVMA guidelines also feature pointers on carrying out the four steps listed above.

CDC positive-prevention advice spells out recommendations on screening for transmission risk and STIs (Table 1).³ The CDC stresses that most STIs are asymptomatic, so these risky infections remain masked unless lab tests uncover them. CDC and HIVMA guidelines outline asymptomatic STI screening advice by (1) initial versus subsequent patient visit, (2) gender, and (3) risk (Table 2).

Patients can even test themselves for gonorrhea and chlamydia in an HIV clinic, according to results of a large London study.¹⁷ In this nurse-led self-screening program, HIV-positive men and women are invited to collect specimens by self-swabbing. Diagrams on rectal, pharyngeal, and vaginal self-swabbing are posted in clinic rest rooms. Staff screens samples with nucleic acid amplification tests.

The 976 screens completed over 8 months in people without STI symptoms disclosed 143 infections (14.6%), at rates of 17.4% in MSM, 2.1% in heterosexual men, and 1.5% in women.¹⁷ Six people with a self-detected STI had a transient spike in HIV load. Among 78 people taking antiretrovirals at STI diagnosis, 72 had a viral load below 40 copies/mL and 6 had a load between 40 and 70 copies/mL. The researchers recommend STI screening for MSM every 4 months and annual testing for heterosexuals. They suggest this approach "may address some of the barriers to screening in this population."

The Health Resources and Services Administration (HRSA) 2011 Guide for HIV/AIDS Clinical Care includes a useful table (on pages 134 and 135) suggesting questions to ask and assessments for (1) sexual practices, (2) partner notification, (3) STI screening, and (4) drug and alcohol use.¹⁸