Simulations of college campus mpox outbreaks demonstrate the importance of detection, isolation

Future outbreaks of mpox on college campuses can be contained with early detection and isolation of symptomatic cases, a study finds.

While CDC data shows that mpox cases in the United States have declined since the peak of the outbreak in July and August 2022, Alexandra SavinkinaMSPH, A PhD student at Yale School of Medicine, and colleagues note that men who have sex with men (MSM) are still a vulnerable population, as are individuals in academic settings because college-age individuals represent half of all sexually transmitted infections in the country.

“Thus, mpox may still be emerging, if sporadically, among young MSM and other sexually active individuals, including on college campuses, with ongoing public health and economic implications for these institutions,” they wrote. History of internal medicine.

Researchers used a mathematical model to estimate the likelihood of an mpox outbreak in a residential college setting and determine how it might spread. They also analyzed the impact of interventions such as case detection, isolation, quarantine and vaccination.

The stochastic dynamic model, titled SEIR, simulates transitions between four phases: susceptible, pre-symptomatic, symptomatic and recovered.

The study group consisted of 6,500 hypothetical college students, who were divided into low- and high-risk infection groups. At the beginning of the semester, if only one person was infected and thus classified as high risk, all other students were classified as susceptible.

The high-risk group consisted of 650 students, or 10% of the total group, based on estimates of the 18- to 24-year-old MSM population.

Following 1,000 simulations of mpox transmission, Savinkina and colleagues found that, regardless of student identification and isolation, there was a:

• 82% probability of outbreak within the high-risk group; and
• 83% probability of cases in low risk group.

This resulted in an average additional 124 cases (95% CI, 3-326) for the high-risk group and 59 cases (95% CI, 1-184) for the low-risk group.

With the identification and isolation of symptomatic individuals, the probability of outbreaks in the high-risk group decreased to 51%, and the probability of cases in the low-risk group decreased to 29% when 80% of cases were detected.

The researchers noted that the average number of cases dropped below 10 when 80% of cases were detected for both groups.

“The maximum isolation capacity required was 47 when 50% of students were detected and isolated,” they wrote.

According to Savikina and colleagues, reactive vaccines did not reduce the likelihood of outbreaks when 50% of cases were detected and isolated, nor did quarantines. However, both reduced the mean number of cases when the high-risk group’s baseline reproductive number was 2.4.

In addition, “when 50% of the high-risk group was vaccinated with mpox before the start of the simulation, the probability of an outbreak beyond the initial cases was reduced,” the researchers wrote. “Assuming no identification and isolation, the probability of an outbreak was 76% in the high-risk group and 78% in the low-risk group.”

When detection and isolation were considered below 80%, the mean number of cases decreased from 33% to 82% for the high-risk group and from 50% to 72% for the low-risk group.

Savinkina and colleagues said the model “provides the basis for contingency planning for college administrators” in the event of an mpox outbreak on a residential campus.

“Our study clearly shows that without intervention to address the introduction

mpox on campus, outbreak likely; Therefore, preparing for such a situation is a prudent course,” they wrote, because while the interventions demonstrated are simple and effective, planning for a disaster “offers few downsides for administrators.”

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