People living with HIV are not more likely to be hospitalized with severe mpox (formerly known as monkeypox) unless they have advanced immune suppression, underscoring the importance of prompt antiretroviral treatment, according to study findings presented at the International AIDS Society Conference on HIV Science (#IAS2023).

To that end, experts recommend that people who present for mpox vaccination, testing or treatment should be tested for HIV if they do not already know their status and linked to care if they are not on antiretroviral therapy.

“For individuals with unknown HIV status, mpox testing can be an opportunity for HIV testing, prevention and care,” presenter Ana Hoxha of the World Health Organization (WHO) said at an IAS news briefing.

Mpox cases have declined dramatically since the outbreak peaked late last summer. To date, the Centers for Disease Control and Prevention (CDC) has identified 30,637 mpox cases in the United States, while WHO has tallied 88,600 cases worldwide, resulting in 152 deaths. Most cases outside of Africa have been among gay, bisexual and other men who have sex with men.

Around 40% of people diagnosed with mpox in the United States were living with HIV, but HIV-positive people accounted for more than 80% of those hospitalized, according to the CDC. A more recent CDC analysis found that most people who have died of mpox in the United States were Black gay men with AIDS.

At this year’s Conference on Retroviruses and Opportunistic Infections, researchers reported that mpox can be much more severe for people with HIV who have a very low CD4 T-cell count, leading them to call for mpox to be classified as an AIDS-defining opportunistic infection. Those findings were based on an international analysis of nearly 400 mpox cases among HIV-positive people with a CD4 count below 350.

At IAS 2023, Hoxa presented findings from a larger analysis based on global surveillance data reported to WHO. Among the more than 82,000 mpox cases reported between January 2022 and January 2023, about 32,000 (39%) had information on their HIV status. Of these, 52% were living with HIV.

Consistent with previous reports, most were men who have sex with men, and about 80% reported that sex was their most likely route of mpox acquisition. People with HIV were more likely than HIV-negative people to have other concurrent sexually transmitted infections (5.5% versus 3.8%).

Among the 16,633 HIV-positive people diagnosed with mpox, nearly a quarter had immune suppression due to advanced HIV or another cause, compared with less than 1% of HIV-negative people. A total of 58 HIV-positive people with mpox died, compared with just four HIV-negative people.

Overall, people with HIV people were significantly more likely to be hospitalized than HIV-negative people with mpox (4.3% vs 3.0%) and they had a substantially higher risk of death (0.3% vs 0.03%). But while immunocompromised people living with HIV were about twice as likely to be hospitalized, the risk for HIV-positive people with an adequate CD4 count was similar to that of HIV-negative people without immune suppression.

Hoxa also reported that HIV-positive and HIV-negative people without advanced immune suppression had “similar clinical presentation,” while immunocompromised people with HIV had more severe mpox manifestations. The most common symptoms were rash (including genital rash) and fever, reported by more than half of both HIV-positive and HIV-negative people.

Women, young children, people over age 65 and immunocompromised HIV-negative people were also more likely to be hospitalized with mpox, but cases were rare in these populations, Hoxa reportd. She cautioned that the study findings may not be applicable to the 60% of reported cases without information about their HIV status.

In light of these findings, Hoxa’s team advised that health systems should ensure that people living with HIV know their status and are linked to care and antiretroviral treatment, which would lower their risk for severe mpox complications. Further, WHO recommends that countries should integrate mpox prevention, testing and care with existing HIV and sexually transmitted infection prevention and control programs.

Click here to read the study abstract.
Click here for more news about mpox.

Click here for more reports from IAS 2023.