Editor's Note: At the recent 2025 Asia-Pacific AIDS & Co-Infections Conference (APACC 2025), Dr. Thomas Fitzpatrick from the University of Washington presented his study titled "Pay-It-Forward and Social Network Distribution to Increase Doxy-PEP Uptake among MSM in China." Infectious Disease Frontier conducted an exclusive interview where Dr. Fitzpatrick shared in-depth perspectives on the operational mechanisms, quality control protocols, sustainability frameworks, and localized implementation strategies of the Pay-It-Forward model.IDF: In your research conducted in China, how does the Pay-It-Forward mechanism alter the willingness to pay for Doxy-PEP among men who have sex with men (MSM)?
Dr. Fitzpatrick: I believe the Pay-It-Forward mechanism operates in several ways. First, it functionally reduces costs for individuals who might otherwise struggle to afford the out-of-pocket expenses associated with DoxyPEP. However, I contend that the primary reason Pay-It-Forward increases DoxyPEP uptake isn’t actually cost-related. When people participate in this model, they develop a sense of responsibility—knowing someone else has cared for them, they feel compelled to care for others. They also experience the warmth of generosity. Having been supported themselves, they begin to value their own well-being and that of others in their community. Another key benefit of the Pay-It-Forward model for DoxyPEP adoption is that DoxyPEP is unfamiliar to many men. If someone in their community supports and donates toward DoxyPEP, it builds trust in this new approach to protecting their health.
IDF: Compared to traditional delivery methods, what advantages does social network distribution offer? How does this model ensure the quality of medical services?
Dr. Fitzpatrick: I believe the primary advantage of social network distribution is reaching individuals who are not yet accessing services. While some community members already consult us as physicians or public health professionals—and thus have existing service connections—many still lack essential sexual healthcare despite its availability. We must therefore develop new strategies to engage those not seeking conventional care. Social network distribution achieves this by leveraging personal connections: reaching people through friends and sexual partners. This approach’s true value lies in its ability to deliver sexual health services beyond clinics and even community-based organizations, directly engaging those disconnected from care systems.
Regarding ensuring service quality: our co-creation methodology addresses this. During intervention design, we collaborated with researchers, clinicians, community members, and community-based organizations to develop educational materials. These co-created resources clearly explain DoxyPEP’s purpose and safe, effective usage protocols. Consequently, social network distribution delivers both DoxyPEP and these rigorously vetted materials.
IDF: After the initial free medication supply is exhausted, can this community-based mutual aid model sustain drug provision? And is this approach viable in the long term?
Dr. Fitzpatrick: The sustainability of Pay-It-Forward is a key consideration for us. While some view this model as a potential replacement for governmental or community financial support, that is not its intended purpose. Rather, Pay-It-Forward is designed to function synergistically with public funding: integrating government health subsidies, public health infrastructure, community resources, and donor contributions. It is unrealistic to expect this model to fully cover healthcare service costs independently. Instead, it serves as an effective mechanism for cost-sharing between local public health systems, government entities, and the community itself.
IDF: For countries/regions with no prior implementation of this model, what initial support would you recommend local health authorities, medical institutions, and community service centers provide to adopt this approach?
Dr. Fitzpatrick: The Pay-It-Forward model is not universally applicable. Its implementation requires careful adaptation to local community contexts and specific circumstances. Therefore, I strongly advise against directly replicating our Chinese implementation case studies without modification. Essential adjustments must always be made when introducing this intervention to different regions and populations.
To facilitate this process, we have collaborated with the World Health Organization (WHO) and other international bodies to develop evidence-based implementation guidelines, publicly accessible online. Interested practitioners may search for ‘Pay-It-Forward’ to locate these resources for contextual adaptation. Additionally, our team remains available for direct consultation to share implementation experiences.
- University of Washington – School of Medicine
- University of North Carolina (UNC) – South China STD Research Training Center
Thomas Fitzpatrick, MD, is a board-certified internal medicine physician and infectious diseases fellow specializing in improving healthcare for people who use substances. Dr. Fitzpatrick provides healthcare rooted in a harm reduction philosophy and approach. Dr. Fitzpatrick’s clinical expertise includes treating infections associated with drug use and helping people who use substances achieve their health goals.
