Research in the Keesing Lab focuses on how ecological communities respond to changes in biological diversity, with a particular focus on how human risk of exposure to infectious diseases is affected by changes in the environment. We have studied how the loss of large mammals affects the ecology of African savannas, and how changes in the diversity and composition of ecological communities influence the transmission of pathogens, particularly tick-borne diseases in the eastern United States. Students in the lab are also involved with a number of other projects, including studies of the invasive plant garlic mustard (Alliaria petiolata), the non-target effects of the fungal pathogen Metarhizium anisopliae, and the distribution of mammals in response to land use in Dutchess County, New York. Current major projects in the lab are described briefly below.

Current projects

Reducing tick-borne disease incidence

We are in the final year of a large-scale project testing whether two promising tick-reduction treatments can, either individually or in combination, reduce the actual number of human cases of Lyme and other tick-borne diseases.  Collaborators: Rick Ostfeld, the CDC, the NYS Department of Health, and the Dutchess County Department of Health.

Modeling covid transmission at small colleges

With support from NSF, I have been working with a team of faculty and undergraduates in math and computer science to model transmission of covid-19 at small colleges. We published a pre-print of our work, including specific recommendations, in summer 2020, and are currently expanding that work for 2021.

Biodiversity and infectious diseases

With support from NSF's OPUS program, I am writing several review papers about the effects of biodiversity on infectious diseases. These papers explore the effects of biodiversity, and particularly biodiversity loss, on the emergence and transmission of zoonotic diseases, but also other diseases of animals and plants.

Wildlife and livestock in African savannas

With support from NSF, we have been studying ecological interactions between livestock and wildlife, particularly how the presence of each group affects the abundance of ticks in the landscape, and the well-being of local people. Collaborators: Brian Allan, Becky Chaplin-Kramer, Heather Tallis, Spencer Wood, Rick Ostfeld.

Other projects

I am a co-director of the Research Experience for Undergraduates (REU) program at the Cary Institute of Ecosystem Studies in Millbrook, New York. Working closely with a mentor scientist, students in this program define a research question and hypotheses, develop and implement the project, analyze their data, give an oral presentation in a formal symposium, and write a paper. In addition, students participate in enrichment activities to support the theme of the program -- translational ecology. Collaborators: Alan Berkowitz, Stuart Findlay, Shannon LaDeau, Aude Lochet

I am participating in a project, funded by NSF's EEID program, to study the assembly of viromes in mice and ticks. We hypothesize that a comparative analysis of mouse and tick viromes will elucidate the origins, interactions, and transmission dynamics of viruses, including those with the potential to emerge into human populations. Collaborators: Kurt Vandegrift, Rick Ostfeld, Peter Hudson, Barbara Han, Amit Kapoor, Laura Kramer.