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Dr. Richard S. Ostfeld

Disease Ecologist | PhD, University of California, Berkeley

disease ecology, Lyme disease, West Nile virus

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Richard Ostfeld studies the ecology of infectious diseases, including Lyme and other tick-borne diseases. By understanding the factors that influence tick abundance and infection, Ostfeld and his team can predict when and where exposure to tick-borne diseases will be high.

Ostfeld’s predictions are based on decades of research that places ticks and the pathogens they transmit in the context of forest food webs. Blacklegged ticks feed on many species of vertebrate hosts, but these hosts differ dramatically in their quality. Some host species kill many ticks but others are more permissive; some host species infect ticks with pathogens but others do not. Rodents such as white-footed mice and eastern chipmunks are high-quality hosts for ticks and for tick-borne pathogens, whereas most other mammals and birds are not. Understanding the ecological factors that affect the abundance of rodent versus nonrodent hosts enhances predictive power.

Changing climatic conditions can affect tick survival and reproduction. Ostfeld studies the effects of environmental variables on tick survival and behavior to predict where Lyme disease will spread as the climate warms.

Ostfeld has studied the relationship between land use and infectious disease for over 25 years. Development of forested areas can degrade or fragment wildlife habitat, causing species diversity to decline. Predators like foxes and bobcats, which feed on mice, are sensitive to fragmentation. The loss of predators can lead to more mice and fewer non-mouse hosts for ticks, increasing the abundance of Lyme-infected ticks and disease risk for humans. Similar relationships between habitat destruction, biodiversity loss, and increased pathogen transmission characterize many infectious diseases worldwide.

In addition to understanding and predicting risk of human exposure to tick-borne diseases, Ostfeld is interested in preventing illness. Together with Felicia Keesing, he is leading a major study of the efficacy of tick-control methods in residential neighborhoods. The team has found that strong reductions in tick abundance and tick infection can reduce disease incidence in outdoor pets but not in people, indicating that increased awareness that supports tick avoidance, detection, and removal will remain the primary method of Lyme disease prevention.

Keesing, Felicia, and Richard S. Ostfeld. (FEB) 2024. “The More, The Healthier: Tree Diversity Reduces Forest Pests And Pathogens”. Plos Biology 22 (2). doi:10.1371/journal.pbio.3002525.
Ostfeld, Richard S., Sahar Adish, Stacy Mowry, William Bremer, Shannon Duerr, Andrew S. Evans, Ilya R. Fischhoff, et al. 2024. “Effects Of Residential Acaricide Treatments On Patterns Of Pathogen Coinfection In Blacklegged Ticks”. Parasitology. Cambridge University Press (CUP), 1-7. doi:10.1017/s0031182024000349.
Keesing, Felicia, Emma Tilley, Stacy Mowry, Sahar Adish, William Bremer, Shannon Duerr, Andrew S. Evans, et al. 2023. “Spatial Variation In Risk For Tick-Borne Diseases In Residential Areas Of Dutchess County, New York”. Plos One 18 (11). Public Library of Science (PLoS): e0293820. doi:10.1371/journal.pone.0293820.
Ostfeld, Richard S., S Mowry, W Bremer, S Duerr, AS Evans, IR Fischhoff, AF Hinckley, et al. (MAR 1) 2023. “Impacts Over Time Of Neighborhood-Scale Interventions To Control Ticks And Tick-Borne Disease Incidence”. Vector-Borne And Zoonotic Diseases 23 (3): 89-105, . doi:10.1089/vbz.2022.0094.
Brunner, JL, Shannon L. LaDeau, M Killelea, E Valentine, M Schierer, and Richard S. Ostfeld. (2023 APR 26AD) 2023. “Off-Host Survival Of Blacklegged Ticks In Eastern North America: A Multistage, Multiyear, Multisite Study”. Ecological Monographs. doi:10.1002/ecm.1572.
Ostfeld, Richard S., and F Keesing. (MAY 13) 2023. “Does Experimental Reduction Of Blacklegged Tick (Ixodes Scapularis) Abundance Reduce Lyme Disease Incidence?”. Pathogens 12 (5). doi:10.3390/pathogens12050714.
Keesing, Felicia, Stacy Mowry, William Bremer, Shannon Duerr, Andrew S. Evans, Ilya R. Fischhoff, Alison F. Hinckley, et al. 2022. “Effects Of Tick-Control Interventions On Tick Abundance, Human Encounters With Ticks, And Incidence Of Tickborne Diseases In Residential Neighborhoods, New York, Usa”. Emerging Infectious Diseases 28 (5). Centers for Disease Control and Prevention (CDC): 957-966. doi:10.3201/eid2805.211146.
Ecke, Frauke, Barbara A. Han, Birger Hörnfeldt, Hussein Khalil, Magnus Magnusson, Navinder J. Singh, and Richard S. Ostfeld. 2022. “Population Fluctuations And Synanthropy Explain Transmission Risk In Rodent-Borne Zoonoses”. Nature Communications 13 (1). Springer Science and Business Media LLC. doi:10.1038/s41467-022-35273-7.
Mowry, Stacy, Jennifer Pendleton, Felicia Keesing, Marissa Teator, and Richard S. Ostfeld. 2022. “Estimates Of Wildlife Species Richness, Occupancy, And Habitat Preference In A Residential Landscape In New York State”. Urban Ecosystems. Springer Science and Business Media LLC. doi:10.1007/s11252-022-01318-4.
Vannier, Edouard, Luciana M Richer, Duy M Dinh, Dustin Brisson, Richard S. Ostfeld, and Maria Gomes-Solecki. 2022. “Deployment Of A Reservoir-Targeted Vaccine Against Borrelia Burgdorferi Reduces The Prevalence Of Babesia Microti Coinfection In Ixodes Scapularis Ticks”. The Journal Of Infectious Diseases, jiac462+. doi:10.1093/infdis/jiac462.
Heske, Edward J, Richard S. Ostfeld, Sergio Ticul Álvarez-Castañeda, Barry J Fox, and William F Laurance. 2022. “Obituary: Dr. William Z. Lidicker, Jr. (1932–2022)”. Journal Of Mammalogy, gyac109+. doi:10.1093/jmammal/gyac109.
Ostfeld, Richard S., and Felicia Keesing. 2022. “The Ecology Of Infectious Diseases: An Homage To Multi-Factor Perspectives”. Therya 13: 39-44, . doi:10.12933/therya-22-1183.
Kumar, D, LP Downs, A Adegoke, E Machtinger, Kelly M. Oggenfuss, Richard S. Ostfeld, M Embers, and S Karim. (FEB) 2022. “An Exploratory Study On The Microbiome Of Northern And Southern Populations Of Ixodes Scapularis Ticks Predicts Changes And Unique Bacterial Interactions”. Pathogens 11 (2). doi:10.3390/pathogens11020130.
Ostfeld, Richard S., Kathleen C. Weathers, David L. Strayer, and Gene E. Likens. 2021. “Ecology Of Lyme Disease”. In Fundamentals Of Ecosystem Science, 2ndnd ed.. London, UK: Academic Press.
Keesing, Felicia, D. J. McHenry, M. H. Hersh, and Richard S. Ostfeld. 2021. “Spatial And Temporal Patterns Of The Emerging Tick-Borne Pathogen Borrelia Miyamotoi In Blacklegged Ticks (Ixodes Scapularis) In New York”. Parasites & Vectors 14 (1). Springer Science and Business Media LLC. doi:10.1186/s13071-020-04569-2.
Keesing, Felicia, and Richard S. Ostfeld. 2021. “Impacts Of Biodiversity And Biodiversity Loss On Zoonotic Diseases”. Proceedings Of The National Academy Of Sciences 118 (17). Proceedings of the National Academy of Sciences: e2023540118. doi:10.1073/pnas.2023540118.
Vila, Montserrat, Alison M Dunn, Franz Essl, Elena Gomez-Diaz, Philip E Hulme, Jonathan M Jeschke, MartÍn A Nunez, et al. 2021. “Viewing Emerging Human Infectious Epidemics Through The Lens Of Invasion Biology”. Bioscience. Oxford University Press (OUP). doi:10.1093/biosci/biab047.
Heaney, Christopher D., Katherine A. Moon, Richard S. Ostfeld, Jonathan Pollak, Melissa N. Poulsen, Annemarie G. Hirsch, Joseph DeWalle, John N. Aucott, and Brian S. Schwartz. 2021. “Relations Of Peri-Residential Temperature And Humidity In Tick-Life-Cycle-Relevant Time Periods With Human Lyme Disease Risk In Pennsylvania, Usa”. Science Of The Total Environment 795. Elsevier BV: 148697. doi:10.1016/j.scitotenv.2021.148697.
Aristizabal-Henao, Juan J., Hannah Brown, Emily K. Griffin, Richard S. Ostfeld, Kelly M. Oggenfuss, Brandon M. Parker, Samantha M. Wisely, and John A. Bowden. 2021. “Ticks As Novel Sentinels To Monitor Environmental Levels Of Per- And Polyfluoroalkyl Substances (Pfas)”. Environmental Science: Processes & Impacts. Royal Society of Chemistry (RSC). doi:10.1039/d1em00209k.
Rubino, Francesca I., Kelly M. Oggenfuss, and Richard S. Ostfeld. 2021. “Effects Of Physical Impairments On Fitness Correlates Of The White-Footed Mouse, Peromyscus Leucopus”. Proceedings Of The Royal Society B: Biological Sciences 288 (1962). The Royal Society. doi:10.1098/rspb.2021.1942.



ecology of lyme disease

Lyme Disease: The Ecology of a Complex System
Oxford University Press, 2011

ostfeld book

Infectious Disease Ecology: Effects of Ecosystems on Disease and of Disease on Ecosystems
Princeton University Press, 2008