(P199) Potential mpox transmission among college-attending 18-25-year-olds with opposite-sex contacts in the United States

Background

In the 2022 multinational mpox outbreak, most cases have occurred among gay, bisexual, and other men who have sex with men (MSM), but sexual contacts between men and women may also transmit mpox. However, despite almost 30,000 cases of mpox reported in the United States, there is little evidence of sustained transmission among persons with opposite-sex partners (PWOSP). Here we explore the behavioral conditions that could produce sustained mpox transmission between PWOSP on college campuses, where smaller mixing pools and more frequent sexual activities relative to the general population may increase exposure.

Methods

We develop a baseline dynamic network model (STERGM) using publicly available data from the 2011-2015 cycle of the National Survey of Family Growth (NSFG) to parameterize frequency and duration of three partnership types among college-attending PWOSP: main, casual, and one-time. We then vary the frequency and duration of these partnerships. We track the infection generation of each case (where introduced cases have an infection generation of 0) across all scenarios. To summarize mpox transmission intensity, we calculate the mean infection generation (MIG) of infections. MIG is similar to R₀ but provides a directly measurable estimate of spread across a structured population; MIG >1 indicates sustained transmission of mpox.

Findings

In the baseline model and most additional scenarios, mpox transmission is not sustained (MIG< 0.5). However, sustained transmission is possible given higher frequency of one-time partnerships: increasing from roughly 1 partner per year (as observed in the NSFG) to 1 partner per month leads to MIG=1.4; 2 partners per month leads to MIG=5.4.

Conclusions

Rapid turnover of partners may be necessary for sustained mpox transmission. The MIG is low across many scenarios, suggesting that persistent mpox transmission is unlikely among college-attending PWOSP. However, the lack of recent, detailed data on the mixing patterns, frequency, and type of sexual behaviors of college students of all sexual orientations and gender identities could lead us to misclassify likely mpox transmission. Additional data collection should be considered for the development of robust models to understand the risk of mpox and other sexually transmitted infections among all college-attending students in the United States.