Katherine P. Lemon, MD, PhD

  • Associate Member of the Staff

    Assistant Professor of Pediatrics, Harvard Medical School 

  • forsyth.org:klemon:Email
  • Lab site
  • Publications

Bacteria live on us, “in” us, and on surfaces all around us. Katherine Lemon, a pediatric infectious disease specialist, is trying to figure out how the good bacteria in the nose and throat help keep the “bad” bacteria out or, at least, under control. In addition to her work in the lab at Forsyth, Lemon sees patients at Boston Children’s Hospital. 

“As a scientist, I am intrigued by why things happen and as a clinician, I want to help patients,” says Lemon. “I envision a future in which these two worlds are closely aligned and we sample the microbiome of every child during routine well-child visits early in life. Knowing how a child’s microbial communities develop may well be an invaluable tool for keeping children healthy for their lifetimes.”

Lemon’s research focuses on two bacteria commonly found in the healthy upper respiratory tract that are also among the most significant bacterial pathogens, Staphylococcus aureus and Streptococcus pneumoniae. The disease burden of these pathogens is particularly high in children. The emergence and spread of antibiotic resistant bacteria, such as community acquired-methicillin resistant S. aureus (CA-MRSA), accentuates the urgent need for new therapies to both treat and prevent these infections.  

Many people live with these bacteria and never get sick. Interestingly, some people do not carry either S. aureus or S. pneumoniae and are, therefore, at low risk for infection. This leads to the hypothesis that, among the constituents of nostril and throat microbiota, there are beneficial microbes that interfere with pathogen carriage. Such beneficial bacteria could be the basis for novel prophylactics/therapeutics. Working to understand the role and dynamics of human microbiota, Lemon’s long-term goal is to develop new, and sustainable, approaches to manage the composition of upper respiratory tract microbiota in order to prevent infections. 


Harvard University, AB, 1987, Near Eastern Languages & Civilizations
Massachusetts Institute of Technology, PhD, 2000, Biology
Harvard Medical School, MD, 2001