Population Biology of Infectious Disease

Evolution of Drug Resistance
Genetic markers are powerful tools in tracing the evolutionary history of organisms. We exploit genetic tools to determine how drug resistant mutations originate and spread in different populations and how this is influenced by ecological factors such as transmission intensity and host immune factors.

Recent publications:

• McCollum AM, Mueller K, Villegas L, Udhayakumar V, Escalante A. 2007. "Common origin and fixation of Plasmodium falciparum dhfr and dhps mutations associated with sulphadoxine-pyrimethamine resistance in a low transmission area in South America." Antimicrobial Agents and Chemotherapy 51 (6): 2085-2091.
• McCollum AM, Poe A, Hamel M, Huber C, Zhou Z, Shi YP, Ouma P, Vulule J, Bloland P, Slutsker L, Barnwell JW, Udhayakumar V, Escalante AA. 2006. "Antifolate resistance in Plasmodium falciparum: multiple origins and identification of novel dhfr alleles." J. Infect. Dis. 194: 189-97.

Ecology of vector-borne & zoonotic diseases
The evolutions of organisms are influenced by ecological factors. For vector-borne and zoonotic diseases both the host and intermediary host will play significant role in shaping the evolutionary history of pathogen. Among host factors, both acquired immune factors and innate immune factors including the natural variation in the host genetic structure will be important determinants of selection and maintenance of evolutionary changes in the parasites. Our laboratory is investigating how the host genetic and immune factors influence parasite evolution.

Recent publications:

• Keen J, Serghides L, Ayi K, Patel SN, Ayisi J, van Eijk A, Steketee R, Udhayakumar V, and Kain KC. 2007. "HIV Impairs Opsonic Phagocytic Clearance of Pregnancy-Associated Malaria Parasites." PLOS Medicine, 4(5): e181.
• Ned R, Moore JM, Chaisavaneeyakorn S, and Udhayakumar V. 2005. "Modulation of immune responses during HIV-malaria coinfection in pregnancy." Trends Parasitol. 21(6):284-91.
• Aidoo M, Terlouw DJ, Kolczak MS, McElroy PD, ter Kuile F, Kariuki S, Nahlen BL, Lal A, and Udhayakumar V. 2002. "Protective effects of the sickle cell trait gene against malaria morbidity and mortality." Lancet 359: 1311-1312