Background Disparities in mortality in HIV-associated Kaposi’s sarcoma have been described, particularly in Black men in the southern United States. It is unclear if there are racial/ethnic differences in the seroprevalence of Kaposi’s sarcoma-associated Herpesvirus (KSHV) that may be contributing. Methods This is a cross-sectional study of men who have sex with men (MSM) and transgender women (TGW) with HIV. Participants were recruited from an outpatient HIV clinic in Dallas, Texas for a one-time study visit and were excluded from analysis if they had any history of KSHV disease. Plasma was tested for antibodies to KSHV K8.1 or ORF73 antigens, and KSHV DNA was measured in oral fluids and blood by PCR. KSHV seroprevalence and viral shedding in blood and oral fluids were calculated. Additionally, independent risk factors for KSHV seropositivity were assessed by multivariable logistic regression analysis. Results 205 participants were included in our analysis. Overall, KSHV seroprevalence was high (68%) with no significant difference between racial/ethnic groups. Among seropositive participants, KSHV DNA was detected in 28.6% of oral fluids and 10.9% of peripheral blood specimens, respectively. The factors most strongly associated with KSHV seropositivity were oral-anal sex (odds ratio [OR] 3.02), oral-penile sex (OR 4.63), and methamphetamine use (OR 4.67). Conclusions High local seroprevalence of KSHV is likely a key driver of the high burden of KSHV-associated diseases regionally, though it does not explain the observed disparities in KSHV-associated disease prevalence among racial/ethnic groups. Our findings support that KSHV is primarily transmitted via exchange of oral fluids.

Background Despite a decrease in Kaposi’s sarcoma (KS) cases in much of the US, the incidence of KS and associated mortality is increasing in specific subpopulations, particularly young, African American men in the South. To further understand this disparity, we sought to describe the seroprevalence and risk factors associated with Kaposi’s sarcoma herpesvirus (KSHV) among men who have sex with men (MSM) and transgender women (TGW) with HIV in Dallas, Texas. Methods We enrolled MSM and TGW with HIV and without known KSHV-related disease from a large urban safety-net clinic in Dallas. Blood samples were collected from participants for IgG testing (K8.1 and ORF73), followed by KSHV PCR on blood and saliva samples for those with positive IgG results. We also collected demographics, sexual history, sexual practices, HIV history, substance use, and insurance status. Multivariate logistic regression modeling was performed to identify associations with KSHV seropositivity. Results Of 159 participants, 110 (69.2%) were seropositive for KSHV. Seroprevalence varied by race/ethnicity, with 27/34 (79.4%) Hispanic, 27/37 (73.0%) white, and 54/84 (64.3%) black participants testing positive for KSHV IgG, though this difference was not statistically significant. 31/104 (29.8%) seropositive participants had detectable KSHV in saliva and 10/104 (9.6%) seropositive participants had detectable KSHV in blood. Risk factors independently associated with KSHV seropositivity include oral-anal sex (OR 4.02, 95% CI 1.89 – 8.54), oral-penile sex (OR 3.66, 95% CI 1.16 – 11.57), and methamphetamine use (OR 2.73, 95% CI 1.23 – 6.04). Current CD4 count, HIV viral load, history of intravenous drug use, tobacco or alcohol use were not associated with KSHV seropositivity. Table 1. Patient Characteristics Conclusion We found that over two-thirds of MSM and TGW with HIV in Dallas are KSHV seropositive, which is relatively high compared to other studies of US MSM with HIV (30-70%). In our study, KSHV was more common among Hispanic and white individuals, and was associated with higher rates of oral sex and methamphetamine use. Differences in KSHV seroprevalence alone are unlikely to explain racial disparities in the incidence of KS. Further study is needed to better understand drivers of KSHV infection and KSHV-related diseases in highly impacted groups in the US. Disclosures All Authors: No reported disclosures