PhD defence Achilleas Tsoumanis

Supervisors

• Prof. dr. Christopher Kenyon (ITM)

• Prof. dr. Niel Hens (University of Antwerp) 

Abstract

This thesis explores the impact of STI screening and treatment strategies on gonorrhea, chlamydia, and antimicrobial resistance among MSM in Belgium by integrating systematic review, empirical data analysis, and network modelling. It begins with a review of existing evidence on the effects of screening, identifying key gaps that motivate the need for improved modelling. A mathematical model is then developed to assess the impact of screening coverage on gonorrhoea prevalence. Limitations in key behavioural parameters are identified, such as partnership duration and homophily. These therefore necessitate empirical estimation. Using primary data, these parameters are refined to enhance model accuracy. The improved model is then applied to evaluate the effects of different gonorrhoea treatment strategies on antimicrobial-resistant gonorrhoea and chlamydia, as well as the impact of different screening strategies on STI prevalence. The findings highlight the importance of optimizing screening and treatment policies to balance infection control with resistance prevention, providing valuable insights for public health interventions.