Estimating Partnership Duration among MSM in Belgium-A Modeling Study

Area of Science:

• Epidemiology
• Network Science
• Mathematical Biology

Background:

• Mathematical modeling is crucial for understanding infection transmission and intervention effectiveness.
• A significant limitation in existing models is the scarcity of reliable social and behavioral parameters.
• This data gap hinders the validity and interpretation of modeling study results.

Purpose of the Study:

• To develop a network model simulating sexual acts among men who have sex with men (MSM) in Belgium.
• To address the lack of empirical social network and behavioral data in scientific literature.
• To estimate key parameters for network specification in epidemiological models.

Main Methods:

• Utilized data from the European MSM Internet Survey 2017.
• Developed a network model for 10,000 MSM, simulating daily sex acts with different partner types (steady, casual, one-off).
• Employed model calibration to estimate partnership duration and homophily rates, matching cumulative partner distributions.

Main Results:

• Estimated average partnership durations: steady (1065–1409 days), assortative high-activity (4–6 days), assortative low-activity (251–299 days), and disassortative persistent casual (8–13 days).
• Durations varied across three different definitions of activity levels.
• Successfully provided a method to estimate crucial parameters for network specification.

Conclusions:

• The study successfully addresses the scarcity of high-quality social network and behavioral data in the literature.
• The developed network model and estimated parameters enhance the accuracy of infection transmission models.
• This research provides valuable insights for public health interventions targeting MSM populations.