Mat Southwell is Managing and Technical Director of Coact Technical Support. Coact is a community-led training and consultancy company that supports harm reduction, drug treatment, and community mobilisation with people who use drugs in international development settings. Mat has supported client literacy and choice in Unitaid study.

Dr Karin Hatzold, MD, MPH, is a public health physician and PSI’s Global Infectious Diseases Lead, based in Cape Town, South Africa. She has more than 25 years of experience leading the development, evaluation and scale-up of innovations in infectious disease diagnostics, prevention and treatment across sub-Saharan Africa. Dr Hatzold is currently the Principal Investigator for Unitaid-funded implementation research evaluating the acceptability, feasibility and effectiveness of low-dead-space syringes (LDSS) and long-acting depot buprenorphine (LADB) within harm reduction programmes in South Africa and Nigeria. This work focuses on generating evidence to inform differentiated, person-centred approaches to opioid dependence treatment and HIV and viral hepatitis prevention and care. She previously led the STAR Initiative, one of the largest global programmes advancing HIV self-testing, and subsequently expanded this work to hepatitis C and COVID-19 self-testing. Evidence generated through these programmes contributed to WHO normative guidance and the adoption and scale-up of self-testing policies and programmes in more than 150 countries. In her current global role, Dr Hatzold also leads work on the introduction and scale-up of long-acting HIV prevention, integrated point-of-care diagnostics, differentiated service delivery, and digital and AI-enabled approaches across Africa. Her work focuses on translating research and technological innovation into policy, sustainable delivery models and large-scale public health impact.

Mat Southwell is Managing and Technical Director of Coact Technical Support. Coact is a community-led training and consultancy company that supports harm reduction, drug treatment, and community mobilisation with people who use drugs in international development settings. Mat has supported client literacy and choice in Unitaid study.