Joseph Lewnard PhD

Assistant Professor, Epidemiology

Postdoctoral, Harvard TH Chan School of Public Health (2018)

PhD, Epidemiology of Microbial Diseases, Yale University (2017)

BA (Hons.), Geography, Music, McGill University (2013)

Research Interests: 
  • Infectious diseases
  • Antimicrobial resistance
  • Public health surveillance
  • Mathematical modeling
  • Bayesian inference
Selected Publications: 

Lewnard JA, Grad YH. Vaccine waning and mumps re-emergence in the United States. Sci Transl Med 2018;

Lewnard JA, Tedijanto C, Cowling BJ, Lipsitch M. Measurement of vaccine direct effects under the test-negative design. Am J Epidemiol 2018;

Lewnard JA, Tähtinen PA, Laine MK, et al. Impact of antimicrobial treatment for acute otitis media on carriage dynamics of penicillin-susceptible and penicillin-nonsusceptible Streptococcus pneumoniae. J Infect Dis 2018;

Lewnard JA, Givon-Lavi N, Weinberger DM, Lipsitch M, Dagan R. Pan-serotype reduction in progression of Streptococcus pneumoniae to otitis media after rollout of pneumococcal conjugate vaccines. Clin Infect Dis 2017;

Lewnard JA, Townsend JP. Climatic and evolutionary drivers of phase shifts in the plague epidemics of colonial India. Proc Natl Acad Sci U S A 2016;


I study the transmission dynamics of infectious disease agents and the effectiveness of interventions such as vaccination. To these ends, I use mathematical and statistical modeling and collaborate closely with investigators leading field studies and disease surveillance. Much of my work centers around the impacts of pneumococcal conjugate vaccines on Streptococcus pneumoniae (an antigenically-diverse pathogen and leading cause of invasive disease, pneumonia, and upper respiratory infections), and lessons for future vaccines targeting limited subsets of pathogen strains. Other ongoing projects address the selection of antimicrobial resistance in pneumococcus, group A Streptococcus, and other commensal pathogens; the re-emergence of vaccine-preventable diseases such as mumps in recent years; and the transmission ecology and prevention of various neglected tropical diseases.

Profile Updated: August 31, 2018