This Week in HIV Research: What We Don’t Know Hurts Them



Even before the COVID-19 pandemic hit the U.S., our health care system was growing increasingly overburdened and undersupported—particularly in poorer or more demographically diverse areas of the country. In HIV, this overarching trend has been exacerbated by brain drain, as older clinicians and service providers retire without being replaced by knowledgeable, well-equipped members of the health workforce.
As a result, we see realities like our top story in this week’s review of recently published medical literature on HIV: Four decades into the epidemic, up-to-date expertise on the virus is often lacking among care providers, as is sensitivity to stigma and discrimination. Research doesn’t highlight issues such as these to cast judgement; it does so to help us understand the scope of the problem, so we can devise solutions that will improve the universe of care and services we’re able to give to our patients and clients who are living with HIV.
Here’s a quick rundown of the studies we recap this week:
- In the southern U.S., rural-serving health care workers often lack basic HIV knowledge, which has implications for stigma and discrimination.
- Most men who have sex with men (MSM) who have condomless sex do so having taken other reliable measures to reduce their HIV risk.
- Integrase inhibitor-based therapy appears to have the greatest immediate impact on onward HIV transmission risk among newly diagnosed MSM.
- Sexually transmitted infection (STI) screening remains irregular among many MSM on pre-exposure prophylaxis (PrEP), particularly for rectal and pharyngeal swabs.
For more details on each of these findings, read onward. To beat HIV, you have to follow the science!

Basic HIV Knowledge Often Lacking Among Health Care Workers in U.S. South, Worsening Stigma
Having at least a basic knowledge about HIV is associated with lower levels of stigma and prejudice among health care workers in the southern U.S.—but many lack even that level of knowledge, researchers reported in the Journal of the National Medical Association.
The study authors invited roughly 600 staff members who worked at medical school-affiliated family medicine clinics serving rural populations to participate in an online survey. Of the 153 people who agreed to do so, 44% were clinical and 56% were non-clinical staff. Participants were graded based on their answers to a questionnaire constructed to gauge HIV stigma and discrimination within the health care workforce.
Knowledge of basic facts about HIV and its transmission was quite variable. Overall, participants scored a C (70 points out of 100 possible) on basic HIV knowledge. Participants averaged a B in two of five stigma domains: stereotypes and prejudicial beliefs. They averaged a D in acceptance of discriminating behaviors; a D in service provision; and an F in perceived risk in practice.
Participants who demonstrated basic HIV knowledge scored better than those who knew little about the virus. “This is promising when considering HIV education as an intervention for reducing HIV stigma even in the context of the rural South,” study authors stated.

Condomless Sex Common Among MSM—but That Doesn’t Equal Higher HIV Risk
While condomless sex was common among 4,923 MSM living with HIV, it mostly did not pose a high risk of HIV transmission once U=U and PrEP were considered, an analysis published in Journal of Acquired Immune Deficiency Syndromes showed.
The study defined “high-risk encounters” as 1) sexual acts engaged by a person living with HIV who did not have sustained viral suppression; 2) condomless sex with an HIV-negative partner not taking PrEP; or 3) condomless sex with a status-unknown partner. Data were self-reported in interviews conducted between 2015 and 2019 by the Medical Monitoring Project and covered 13,024 partnerships, of which 7,768 were HIV-discordant.
Sixty-six percent of participants reported condomless sex, but only 11% reported high-risk sexual activity. Dyad-level analyses showed such acts to be more common among white MSM compared to other races/ethnicities. Black participants were less likely to be virally suppressed, but they were also less likely to have condomless sex. Other findings included racial/ethnic differences in PrEP use and the likelihood of multi-racial partnerships.
“In the context of ending the HIV epidemic, behavioral and clinical surveillance data can help monitor HIV transmission risk and target prevention efforts to reduce transmission among populations at disproportionate risk,” study authors concluded.

Rapid Integrase-Based Treatment Initiation May Prevent More HIV Transmissions Than EFV, DRV
HIV transmission events among MSM become more common the more time elapses between HIV diagnosis and antiretroviral treatment start—and integrase-inhibitor based therapy can blunt early transmission risk more effectively than a regimen based on efavirenz (EFV, Sustiva) or boosted darunavir (DRV, Prezista), a mathematical model published in PLOS One found.
Compared to starting treatment 28 days after diagnosis, initiation of an integrase-based regimen on the same day of a person’s HIV diagnosis was associated with an 88% reduction in HIV transmission risk over the following eight weeks, compared to a 76% reduction on an efavirenz-based regimen and a 58% reduction on a boosted darunavir-based regimen.
Event simulation modeling was based on behavioral data from the START trial and from clinical trials of the antiretrovirals on which this study focused. The model did not consider PrEP use by HIV-negative partners or a difference in HIV prevalence rates by populations.
“Rapid, if not same-day initiation of INSTI-based [antiretroviral treatment] to newly diagnosed HIV-infected MSM has the potential for substantial public health benefits related to decreases in [HIV transmission events],” the study authors concluded. However, rapid antiretroviral treatment start is not enough by itself to curb new seroconversions, they cautioned: Support, including health insurance and counseling, is also needed to keep people in care.

Many MSM on PrEP Not Consistently Screened for STIs
Many MSM who are taking PrEP in the U.S. are not consistently screened for STIs as recommended by Centers for Disease Control and Prevention guidelines, a study published in Clinical Infectious Diseases found.
The findings derive from an analysis of survey data from the ARTnet study, which included 3,259 HIV-negative, PrEP-eligible MSM. During the study period (2017-2019), 19% of participants said they were taking biomedical HIV prevention and 6% said they had previously taken it.
Per CDC guidelines, comprehensive STI screenings are recommended every three to six months for MSM taking PrEP. Among study participants who had ever taken PrEP, consistent screening for STIs varied widely depending on the sampling method: Screening rates were especially low for rectal swabs (57%) and pharyngeal swabs (64%), while they were higher for urine samples (78%) and blood samples (87%).
Rates were especially low among respondents living in the U.S. Southeast, where seven of 12 states have not expanded Medicaid. The study authors noted that even when the costs of PrEP itself are covered, ancillary services, such as STI screenings, may not be; thus, cost may be another barrier to STI testing.
“Infrequent extragenital screening is a public health concern because of the higher prevalence of asymptomatic chlamydia or gonorrhea infections that may remain undetected,” study authors commented. Self-collected swabs or at-home testing may improve rates, they said.
Even as this study highlights relatively poor follow-through on existing STI testing guidelines, a separate study we highlighted several weeks ago in This Week in HIV Research suggested that the guidelines themselves may not be aggressive enough: It found that screening for STIs every three months rather than the current three-to-six month recommendation could further reduce STI incidence rates.