Ottar Bjornstad, Ph.D.

Ottar Bjornstad, Ph.D.

  • Distinguished Professor of Entomology and Biology
  • J. Lloyd & Dorothy Foehr Huck Chair of Epidemiology
W-129 Millenium Science Building
University Park, PA 16802


  • B.A. Biology, University of Oslo, Norway 1991
  • M.S. Zoology, University of Oslo, 1993
  • Ph.D. Ecology, University of Oslo, 1997

Department Focus Areas

Disease Ecology and Biology
Ecological Applications

Research Interests

Population ecology and population dynamics with particular emphasis on mathematical and computational aspects

Research Activities and Interests

Bjørnstad conducts research at the intersection of ecology, mathematical biology and statistics to improve the understanding of outbreaks of agricultural and forest insect pests as well as important vector species. Additionally he works on the spatial and temporal spread of acute diseases such as measles, rubella, whooping cough, influenza, and now COVID-19. He  is also an adjunct professor in statistics and carry out research in statistical ecology and in methods for analyzing spatiotemporal data.

New Book

Epidemics: Models and data using R

Selected Publications

For a complete listing use

Lavine, J.O., Bjørnstad, O.N and Anitia, R. 2021. Immunological characteristics govern the transition of COVID-19 to endemicity. Science 371: 741-745.

Giles, J.R., zu Erbach-Schoenberg, E., Tatem, A.J., Gardner, L., Bjørnstad, O.N., Metcalf, C.J.E. and Wesolowski, A. 2020. The duration of travel impacts the spatial dynamics of infectious diseases. Proceedings of the National Academy of Sciences 117: 22572-22579

Bjørnstad, O.N, Shea, K., Krzywinski, M. and Altman, N. 2020. The SEIRS model for infectious disease dynamics. Nature methods 17: 867-868.

Tian, T., Liu, Y, Li, Y., Wu2, C.-H., Chen, B., Kraemer, M.U.G, Li, B., Cai, J., Xu, B., Yang, Q., Wang, B., Yan, P., Cui, Y., Song, Y., Zheng, P., Wang, Q., Bjornstad, O.N., Yang, R., Grenfell, B.T., Pybus, O.G, and Dye, C. 2020. An investigation of transmission control measures during the first 50 days of the COVID-19 epidemic in China. Science 368: 638-642.

Bjørnstad, O.N, Shea, K., Krzywinski, M. and Altman, N. 2020. Modeling infectious epidemics. Nature methods 17:455-456.

Li, R., Xu, L., Bjørnstad, O.N., Liu, K., Song, T., Chen, A., Xu, B., Liu, B. and Stenseth, N.C. 2019. Climate-driven variation in mosquito density predicts the spatio-temporal dynamics of dengue. Proceedings of the National Academy of Sciences USA 116: 3624-3629.

Dalziel, B.D., Kissler, S., Gog, J. Viboud, C., Bjørnstad, O.N., Metcalf, C.J.E., Grenfell, B.T. 2018. Urbanization and humidity shape the intensity of influenza epidemics in US cities. Science 362: 75-79. 

Tian, H., Hu, S., Cazelles, B., Chowell, G., Gao, L., Laine, M., Li, Y., Yang, H., Li, Y., Yang, Q., Tong, X., Huang, R., Bjornstad, O.N., Xiao, H., Stenseth, N.C. 2018. Urbanization prolongs hantavirus epidemics in cities. Proceedings of the National Academy of Sciences USA 115: 4707-4712.

Li, S-L., Bjørnstad, O.N., Ferrari, M., Mummah, R., Runge, M.C., Fonnesbeck, C., Tildesley, M.J, Probert, W.J.M. and Shea, K. 2017. Essential information: Uncertainty and optimal control of Ebola outbreaks. Proceedings of the National Academy of Science USA 114: 5659–5664.

Bjørnstad, O.N. and Viboud, C. 2016. Timing and periodicity of influenza epidemics. Proceedings of the National Academy of Science USA 113: 12899–12901.

Bhattacharyya, S., Gesteland, P.H., Korgenski, K., Bjørnstad, O.N. and Adler, F.R. 2015. Cross-immunity between strains explains the dynamical pattern of paramyxoviruses. Proceedings of the National Academy of Science USA

Bjornstad, O.N. 2015. Nonlinearity and chaos in ecological dynamics revisited. Proceedings of the National Academy of Science USA 112(20): 6252–6253

Nelson, W.A., Bjornstad, O.N. and Yamanaka, T. 2013. Recurrent insect outbreaks caused by temperature-driven changes in system stability. Science 341: 796-799.

Metcalf, C.J.E., Graham, A.L., Huijben, S., Barclay, V.C., Long, G.H., Grenfell, B.T., Read, A.F. and Bjørnstad, O.N. 2011. Partitioning regulatory mechanisms of within-host malaria dynamics using the effective propagation number. Science 333: 984-988.

Lavine, J., King, A.A. and Bjornstad, O.N. 2011. Natural immune boosting in pertussis dynamics and the potential for long-term vaccine failure. Proceedings of the National Academy of Science USA 108: 7259-7264.

Johnson, D.M., Liebhold, A.M., Tobin, P.C and Bjørnstad, O.N. 2006. Allee effects and pulsed invasion by the gypsy moth. Nature 444: 361-363.

Bjørnstad, O.N., Peltonen, M., Liebhold, A.M. & Baltensweiler, W. 2002. Waves of larch budmoth outbreaks in the European alps. Science 298: 1020-1023.

Bjørnstad, O.N. & Grenfell, B.T. 2001. Noisy clockwork: time series analysis of population fluctuations in animals. Science 293: 638-643.

Bjørnstad, O.N., Sait, S.M., Stenseth, N.C., Thompson, D.J. & Begon, M. 2001. Coupling and the impact of specialised enemies on the dimensionality of prey dynamics. Nature 401: 1001-1006.