My research on the ecology of pathogens is concerned with the study of how interactions with the environment affects the biology of pathogens — in terms of their survival and proliferation in the different ecosystems of the human body (or other hosts), in terms of dispersal routes, in terms of competition for available niches between strains and species, and in terms of invasive ability in various settings. Understanding pathogen ecology is instrumental for gaining insight into the role of the environment as a dissemination route and reservoir of pathogens, as well as how and where pathogen evolution is likely to take place. These processes firmly link pathogen ecology to the study of environmental antibiotic resistance.

This far, my work within this field has mostly been concerned with pathogen dispersal through sewage treatment processes, and how the spatial distribution of Helicobacter pylori and other bacteria in the human stomach affects gastric cancer development. I have also been awarded a four-year grant from FORMAS to study invasion processes in microbial communities. I am, however, also interested in how pathogen dispersal and evolution can be modeled and how concepts from metacommunity theory can be applied to better understand infectious diseases.

Open questions of interest

  1. What are the genetic factors that influence invasion success and resistance to invasion by other species?
  2. What is the role of other bacterial species than Helicobacter pylori in gastric cancer development?
  3. Do different H. pylori strains compete for available niches in the human stomach, or is there a strong founder effect?
  4. What are the implications of spatial distribution of human infections?
  5. What are the dispersal barriers for pathogens, and how do these influence human health?
  6. How do dormant species contribute to infection, disease spread and the “rare biosphere”?

Key publications

  • Thorell K, Bengtsson-Palme J, Liu OH, Gonzales RVP, Nookaew I, Rabeneck L, Paszat L, Graham DY, Nielsen J, Lundin SB, Sjöling Å: In vivo analysis of the viable microbiota and Helicobacter pylori transcriptome in gastric infection and early stages of carcinogenesis. Infection and Immunity, accepted manuscript (2017). doi: 10.1128/IAI.00031-17 [Paper link]
  • Bengtsson-Palme J: Antibiotic resistance in the food supply chain: Where can sequencing and metagenomics aid risk assessment? Current Opinion in Food Science, 14, 66–71 (2017). doi: 10.1016/j.cofs.2017.01.010 [Paper link]