Why study pathogen kinetics?

Pathogen kinetics—how pathogen load changes in the body over the course of an infection—can reveal crucial insights into the biology and epidemiology of infectious diseases.

Pathogen kinetics are the key link between the microbiological and the epidemiological scales. By measuring pathogen kinetics, we can peer into the dynamics of pathogen replication and the immune response – and simultaneously learn about the timing and intensity of infectiousness. By studying pathogen kinetics across diverse pathogen and host populations, we can answer fundamental questions that are essential for a robust outbreak response.

Key Applications of Pathogen Kinetics

Epidemiology

The shape of a pathogen kinetics curve can inform key epidemiological parameters, including the incubation period and generation interval. These values are critical for creating models that predict the pathogen's spread. Pathogen kinetics can also reveal how infectiousness varies across individuals, both in timing and intensity.

Clinical medicine

Many therapeutics must be administered within a narrow window to be maximally effective. Pathogen kinetics can help inform when treatment should be given, and how this timing relates to symptoms or pathogen load. Pathogen kinetics can also play a key role in vaccine and therpauetics trials, revealing how they impact the duration of infection and infectiousness.

Public health

Pathogen kinetics can help inform the design of non-pharmaceutical interventions, like screening and isolation countermeasures. They can also supplement standard case reporting by providing evidence on whether an epidemic is growing or decaying.

The Need for a Centralized Commons

Historically, our understanding of pathogen kinetics has been limited to retrospective analyses, convenience samples, and bespoke, one-off models. Data has been fragmented across institutions, published in inconsistent formats (or not at all), and collected with varying metadata, making large-scale comparison nearly impossible.

The COVID-19 pandemic highlighted the power of pathogen kinetics surveillance but also exposed the urgent need for a unified approach. The Open Pathogen Kinetics Commons (OPKC) is our response to this challenge.

By building a living library of standardized data, we can enable the development of open-source modeling tools, improve study designs, and create a global resource that strengthens our response to both ongoing and future outbreaks.

For more information, see the forthcoming article Integrating viral kinetics into routine outbreak surveillance: challenges, opportunities, and lessons from COVID-19 (Hay, Larremore, Aatresh, and Kissler, 2025).