A Rutgers Health survey of LGBTQ+ individuals in New York and New Jersey reveals that cisgender men, gay individuals and full-time employees had the highest rates of vaccination for Mpox, a viral disease formerly known as monkeypox.

The study in the Journal of Community Health sheds light on vaccination behaviors and access during the 2022 Mpox outbreak.

The results from 2022 appear as health officials warn of a potential resurgence of Mpox cases.

In 2022, the disease disproportionately affected men who have sex with men, leading to a targeted vaccination campaign that appears to have maximized vaccination among those who faced the highest infection risk.

"We were able to add questions about whether or not people had heard about Mpox, how concerned they were, and then when the vaccine became available that July [2022], we added a couple of additional questions about whether they were vaccinated," said Kristen Krause, an assistant professor at Rutgers University's School of Public Health and lead author of the study.

The research team surveyed 253 LGBTQ+ adults in New York and New Jersey, with a subset of 144 participants answering additional questions about vaccination status and access. The study population was predominantly white, full-time workers who identified as gay or lesbian.

Their answers showed that 90.9% of cisgender men and 95.1% of gay-identified participants had either received at least one dose of the Mpox vaccine or intended to get vaccinated. Full-time employees also reported an above-average vaccination rate of 81.6%.

The study also found that HIV-negative individuals were more likely to report difficulty securing a vaccination appointment. This supports previous research suggesting people living with HIV often have easier access to care because of established relationships with healthcare providers.

"If you're already connected to care, it's typically a little bit easier to access," Krause said.

Overall, two-thirds of participants reported they would likely or very likely get vaccinated if the vaccine was easily available, but slightly more than half of all participants found it moderately or very difficult to secure a vaccination appointment.

"A lot of the anecdotes that we'd hear in the city suggested that if appointments were available, they weren't always easily accessible, or they filled up really quickly," Krause said. "People didn't necessarily know where to go. They were only during working hours, which was a problem for some people."

The researchers found no evidence of racial disparities in vaccine access, which is unusual in a public health study and may have been because of the limited sample size.

Pharmaceutical companies have yet to develop an Mpox vaccine, so the vaccination campaign relied largely upon the smallpox vaccine Jynneos. Health officials hoped the close relationship between the smallpox and Mpox viruses would allow Jynneos to provide cross-protection against Mpox.

However, the sudden global demand for the vaccine led to supply shortages. To stretch the limited supply, health authorities in the U.S. adopted a dose-sparing strategy in August 2022. Instead of the standard subcutaneous injection of the full two-injection dose, they authorized intradermal administration of one-fifth of the regular dose.

While this approach allowed for more vaccinations, it also raised questions about efficacy. Preliminary studies have shown promising results, though, with the Centers for Disease Control and Prevention reporting that unvaccinated individuals were about 14 times more likely to get Mpox compared to those who received the vaccine.

As Mpox cases begin to rise again, questions about long-term immunity have emerged. Krause and her colleagues are now calling for research into the durability of vaccine protection, especially among different populations.

"Are those people who got vaccinated in 2022 still enjoying some level of immunity there?" Krause asked. “That’s a critical question right now.”