Infectious Diseases


Region: Africa and North, Central, and South America

These studies investigate the link between biodiversity and immunological disease. Coevolution is thought to maintain geneticdiversity in pathogen and host populations, and to contribute to the complexity of the immune system. Indeed, high levels of genetic variation have been found in the major histocompatibility complex (MHC), a highly polymorphic gene system associated with immunity in a variety of vertebrates. High levels of heterozygosity at MHC loci can be associated with higher levels of parasite and disease resistance. Empirical evidence for an association between MHC variation and pathogen prevalence is needed across a wide range of ecological and demographic conditions. This study will attempt to correlate the extent of genetic diversity in MHC loci with parasite prevalence in free living, natural populations of rainforest birds that vary in population size and degree of geographic isolation.

Current Projects

UCLA/NIH Avian Influenza Project. CTR was awarded a four-year project from the National Institutes of Health/National Institute of Allergy and Infectious Diseases (NIH/NIAID) entitled “Effects of Avian Migration and Anthropogenic Change on the Distribution and Transmission Risks of Avian Influenza.” Click here for more information.

Avian Malaria, Mosquitoes, and Birds in Cameroon
(click here to download PDF)

Related Publications

2014 Fuller TL, Havers F, Xu C, Fang L, Cao W, Shu Y, Widdowson M, Smith TB. Identifying areas with a high risk of human infection with the avian influenza (H7N9) virus in East Asia. Journal of Infection 69:174-181. doi:10.1016/j.jinf.2014.03.006
2014 Harrigan RJ, Sedan R, Chasar AC, Chaves J, Nguyen JT, Whitaker A, Smith TB. New host and lineage diversity of avian haemosporidia in the Northern Andes. Evolutionary Applications. doi:10.1111/eva.12176
2014 Larison B, Njabo KY, Chasar A, Fuller T, Harrigan RJ, Smith TB. Spillover of pH1N1 to swine in Cameroon: an investigation of risk factors. BMC Veternary Research 10:55. doi:10.1186/1746-6148-10-55
2014 Sheta BM, Fuller TL, Larison B, Njabo KY, Ahmed AS, Chasar A, Aziz SA, Khidr AA, Elbokl MM, Habbak LZ, Smith TB. Putative human and avian risk factors for avian influenza virus infections in backyard poultry in Egypt. Veterinary Microbiology 168:208-213. doi:10.1016/j.vetmic.2013.11.010
2014 Harrigan R, Thomassen H, Buermann W, Smith TB. A continental risk assessment of West Nile virus under climate change. Global Change Biology doi:10.1111/gcb.12534
2013 Fuller, T.L., M. Gilbert, V. Margin, J. Cappelle, P. Hosseini, K.Y. Njabo, Z.A. Aziz, X. Xiao, P. Daszak, T.B. Smith. Predicting hotspots for influenza virus reassortment. Emerging Infectious Diseases 19:581-588. PDF
2013 Njabo, K.Y., T.B. Smith, E. Yohannes. Feeding habits of culicine mosquitos in the Cameroon lowland forests based on Stable Isotopes and blood meal analyses. Journal of Parasitology and Vector Biology 5:6-12. PDF
2012 Shafir, S.C., T. Fuller, T.B. Smith, A.W. Rimoin. A national study of individuals who handle migratory birds for evidence of avian and swine influenza virus infections. Journal of Clinical Virology 54(4): 364-7. PDF
2011 Njabo, K.Y., A. J. Cornel, C. Bonneaud, E. Toffelmier, R. N. M. Sehgal, G. Valkiunas, A. F. Russell, and T. B. Smith. Nonspecific patterns of vector, host and avian malaria parasite associations in a Central African rainforest. Molecular Ecology 20: 1049-1061. PDF
2011 Sehgal, R. N. M., W. Buermann, R. J. Harrigan, C. Bonneaud,  C. Loiseau, A. Chasar, I. Sepil, G. Valkiunas, T. Iezhova, S. Saatchi, and T. B. Smith. Spatially explicit predictions of blood parasites in a widelydistributed African rainforest bird. Proceedings of the Royal Society B. 278: 1025-1033. PDF
2010 Harrigan, R. J., H. A. Thomassen, W. Buermann, R. F. Cummings, M. E. Kahn, and T. B. Smith. Economic conditions predict prevalence of West Nile virus. PLoS ONE 5: e15437.
doi:10.1371/journal.pone.0015437. PDF
2010 Fuller, T., S. Saatchi, E. E. Curd, E. Toffelmier, H. Thomassen, W. Buermann, D. F. DeSante, M. P. Nott, J. F. Saracco, C. J. Ralph, J. D. Alexander, J. P. Pollinger, and T. B. Smith. Mapping the risk of avian influenza in wild birds in the U.S. BMC Infectious Diseases 10: 187. doi:10.1186/1471-2334-10-187 PDF
2010 Loiseau, C., T. A. Iezhova, G. Valkiunas, A. Chasar, A. Hutchinson, W. Buermann, T. B. Smith, and R. N. M. Sehgal. Spatial variation of haemosporidian parasite infection in African rainforest bird species. Journal of Parasitology 96: 21-29. doi: 10.1645/GE-2123.1 PDF
2009 Njabo, K. Y., A. J. Cornel, R. N. M. Sehgal, C. Loiseau, W. Buermann, R.  J. Harrigan, J. Pollinger, G. Valkiūnas, and T. B. Smith. Coquillettidia (Culicidae, Diptera) mosquitoes as new natural vectors of avian malaria in Africa. Malaria Journal 8: 193. doi:10.1186/1475-2875-8-193. PDF
2009 Chasar, A., C. Loiseau, G, Valkiūnas, T. Iezhova, T. B. Smith, and R. N. M. Sehgal. Prevalence and diversity patterns of avian blood parasites in degraded African rainforest habitats. Molecular Ecology 18:  4121-4133. PDF
2009 Bonneaud, C, I. Sepil, B. Milá, W. Buermann, J. Pollinger, R. N. M. Sehgal, G. Valki?nas, T. A. Iezhova, S. Saatchi, and T. B. Smith. The prevalence of avian Plasmodium is higher in undisturbed tropical forests of Cameroon. Journal of Tropical Ecology 25: 439-447. PDF
2009 Valkiūnas G., T. A. Iezhova, C. Loiseau, A. Chasar, T. B. Smith, and R. N. M. Sehgal. New malaria parasites of the subgenus Novyella in African rainforest birds, with remarks on their high prevalence, classification and diagnostics. Parasitology Research 104: 1061-1077. PDF
2008 Valkiūnas G., T. A. Iezhova, C. Loiseau, A. Chasar, T. B. Smith, and R. N. M. Sehgal. New species of haemosporidian parasites (Haemosporida) from African rainforest birds, with remarks on their classification. Parasitology Research 103: 1213-1228. PDF
2005 Jones, H.I., R.N.M. Sehgal and T.B. Smith. Leucocytozoon (Apicomplexa: Leucocytozoide) from West African Birds, with descriptions of two species. Journal of Parasitology 29: 397-401. PDF
2005 Valkiunas, G., R. N. M. Sehgal, T. A. Ieezhova, and T. B. Smith. Further observations on the blood parasites of birds in Uganda. Journal of Wildlife Diseases 41: 580-587. PDF
2005 Sehgal, R. N. M., H. I. Jones, and T. B. Smith. Molecular evidence for host specificity of parasitic nematode microfilariae in some African rainforest birds. Molecular Ecology 14: 3977-3988. PDF
2005 Sehgal, R. N. M., H. I. Jones, and T. B. Smith. Blood parasites of some West African rainforest birds. Journal of Veterinary Medical Science 67: 295-301. PDF
2002 Richard, F.A., R. N. M. Sehgal, H. I. Jones, and T. B. Smith. A Comparative Analysis of PCR-based Detection Methods for Avian Malaria, Journal of Parasitology 88: 819-822. PDF
2001 Sehgal, R. N. M., H. I. Jones and T. B. Smith. Host specificity and prevalence of Trypanosoma in the African avifauna: a molecular approach. Molecular Ecology. 10: 2319-2327. PDF

CTR Bird

Center for Tropical Research | UCLA Institute of the Environment and Sustainability
La Kretz Hall, Suite 300 | 619 Charles E. Young Dr. East | Los Angeles, CA 90095-1496

The Center for Tropical Research, located on the third floor of La Kretz Hall, is part of the Institute of the Environment and Sustainability at the University of California, Los Angeles. For general inquiries, contact Christa Gomez, CTR Office Manager, at 310-206-6234, or by email at Visitors are always welcome.

Back to Top