Samuel Kariuki is the Eastern Africa Director of the Drugs for Neglected Diseases initiative (DNDi) since 2023. Additionally, he is a visiting Professor in Tropical Microbiology, Nuffield Department of Medicine, University of Oxford, and Honorary Fellow, Wellcome Trust Sanger Institute, Cambridge, the United Kingdom.

Over the last 20 years he has carried out research on epidemiologic characterization of enteric infections outbreaks, utilizing whole genome sequencing to better understand ecology, and transmission dynamics of bacteria and antimicrobial resistance. Some of the important pathogens of public health significance have included invasive Salmonella, E. coli, Shigella spp, Vibrio cholerae and Campylobacter spp., that are endemic in Kenya and the region. He led the initiative to develop the National Action Plan for reduction and control of Antimicrobial Resistance and sits on the National Antimicrobial Stewardship Advisory Committee that advises Ministries of Health and Agriculture on policy on prudent use of Antimicrobials in human and veterinary medicine.

In addition, he has published on the local epidemiology of antimicrobial resistance especially relating to the human-animal interface. He has co-authored 182 manuscripts in peer-reviewed journals and written chapters in 4 text books in related fields of Antimicrobial resistance and food safety. His data has contributed extensively to policy change in treatment and management of foodborne infections locally and have helped in the understanding of zoonotic infections epidemiology locally and globally. He was principal author of Situation Analysis: Antibiotic Use and Resistance in Kenya, under the Global Antibiotic Resistance Partnership (GARP) and currently a member of the WHO Strategic Advisory Group (SAG-AMR) on AMR.

He holds a Bachelor of Veterinary degree from the University of Nairobi, a Master of Science in Pharmacology & Toxicology from the same university, and a PhD in Tropical Medicine from the University of Liverpool, UK. In 2022, he was awarded Doctor of Science (Honoris causa) by the Liverpool School of Tropical Medicine in recognition of his research in the area of Genomics and Epidemiology of Enteric infections and Antimicrobial resistance.