Estimated Monkeypox Susceptible MSM Population in North Carolina Review

In order to inform public health officials and understand the risk of monkeypox in North Carolina, researchers from across Atrium Health and Wake Forest University School of Medicine estimated the number of men who have sex with men by North Carolina county using the NHANES survey data in order to inform vaccination quantities and priorities given the current limited supply of vaccines.

Public Health

August 11, 2022

How many vaccines do we need?

The 2022 global outbreak of monkeypox virus has been predominantly in gay, bisexual, and other men who have sex with men (MSM). A group of researchers in the Section on Infectious Diseases and the Division of Infectious diseases sought to answer the question of how many MSM could be in the state of North Carolina as well as estimate the proportion of those who had more than one sexual partner in the last year, individuals who represent the highest risk for infection and onward transmission of monkeypox. Understanding these figures will aid in the public understanding of how many vaccines are needed and how to prioritize the limited supply of vaccines.

Key findings

Researchers found that at a minimum roughly 15,700 sexually active MSM in North Carolina should be offered vaccines to reduce the risk of monkeypox infection and to blunt transmission chains, which is unfortunately far greater than the current vaccine supply in North Carolina. Additionally, about 49,400 vaccines should be offered to other members of the MSM community in North Carolina to reduce their risk of infection. These estimates do not include other occupations where there is a high risk for monkeypox exposure including laboratory personnel and front-line healthcare workers with dedicated public health response roles where exposure could rapidly increase with increasing prevalence. Monkeypox is an infectious disease and can infect anyone.

Study limitations

  • The basis for estimating sexual activity and practice relies on the accuracy of responses to the NHANES survey. Because of violence and stigma against MSM, respondents may not be inclined to answer questions about sexual practices, thus these estimates could underestimate the true number of MSM or the number of persons exposed to monkeypox.
  • The NHANES survey is a national level so inferences at the subnational level may have much larger error due. These limitations are more likely to underestimate the eligible population for vaccination, suggesting significant expansion of vaccine supply will be needed in order to contain the current monkeypox outbreak.

Read the full report

The full pre-print is available on medRxiv.



BibTeX citation:
  author = {DeWitt, Michael},
  title = {Estimated {Monkeypox} {Susceptible} {MSM} {Population} in
    {North} {Carolina} {Review}},
  date = {2022-08-11},
  url = {},
  langid = {en}
For attribution, please cite this work as:
DeWitt, Michael. 2022. “Estimated Monkeypox Susceptible MSM Population in North Carolina Review.” August 11, 2022.