Dr. Mignonette Du Plessis

Mignonette Du Plessis is a South African microbiologist and genomic epidemiologist recognized for her work on invasive bacterial and viral pathogens. Affiliated with national public health and academic institutions in South Africa, her research integrates laboratory surveillance, molecular typing, and whole-genome sequencing to inform vaccine policy and outbreak response, particularly in low- and middle-income settings.

Her scholarship centers on Streptococcus pneumoniae, with influential contributions on serotype distribution after conjugate vaccine introduction, clonal dynamics, antimicrobial resistance, and capsule switching as a vaccine escape mechanism. Through large-scale genomic analyses of serotype 1 and emerging lineages such as multidrug-resistant 24F, she has advanced understanding of pneumococcal evolution, transmission, and serotype replacement in Africa and globally.

Du Plessis has also contributed to major collaborative studies on RSV burden, SARS-CoV-2 seroprevalence, influenza trends during the COVID-19 pandemic, diphtheria outbreaks, and meningococcal genomics. This body of work highlights expertise in respiratory pathogen surveillance, outbreak investigation, and translating genomic data into actionable public health strategies.