Ynes Rosa Ortega Associate Professor Center for Food Safety
Portrait of Ynes Rosa Ortega
Mailing Address Griffin, CAES Campus UGA-Melton Building, 350 Woodroof Drive, Griffin, GA 30223
Shipping Address Griffin, CAES Campus UGA-Melton Building, 350 Woodroof Drive, Griffin, GA 30223

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Portrait of Ynes Rosa Ortega


Dr. Ortega’s laboratory is focused on parasites that have been associated with food and water borne outbreaks. Because of current practices in the production and processing of food products, there is a need for studies aimed at the dynamics of disease transmission.

Detection assays that are sensitive and specific for human and animal pathogenic parasites in food products are being evaluated, as well as biological and environmental samples. We focus on the testing, development, and evaluation of methodologies for parasite inactivation in food products, and the study of risk factors associated with parasitic foodborne transmission.

Our goal is the development of safer produce and food products. The parasites currently being studied in this laboratory include Cryptosporidium parvum, Giardia lamblia, Cyclospora cayetanensis, Toxoplasma gondii, and Neospora. Since the U.S. imports a large amount of fresh produce and some of this has been implicated in foodborne outbreaks, it was necessary and logical to initiate a training program where scientists from different institutions could become familiar with these parasites. For this two strategies have been initiated: 1) a training program for international scientists  and 2) informing the scientific community of the importance of food parasitology as an integral part of food safety. Additionally epidemiological studies on diarrheal illness in children in Peru are being developed, particularly looking at risk factors and environmental conditions that favor the presence and survival of these parasites.

AESC 4960, Undergraduate Research. This course offers students the opportunity to participate in a research project while learning microbiological, immunological, and molecular techniques. The course is intended primarily for science majors.

FDST 4800, Special Problems in Food Sciences. This undergraduate course covers foodborne parasites, from the disease, basic biology, and mechanisms of transmission to the specific detection methods in hosts and environmental samples. The understanding of the epidemiology of these diseases and outbreak investigations is also addressed.

FYOS 1001, Foodborne Pathogens: Foods and Public Health. Fall 2016. Students will learn about microorganisms, with a focus on pathogenic organisms that cause illness in humans. We will talk about bacteria, viruses, and particularly parasites. We will also discuss the epidemiology, detection, and control of these pathogens. Students will be taught the basics of food microbiology and the diseases associated with them. At the conclusion of the class, students will have a better understanding of these microorganisms and their importance in food sciences, human and veterinary medicine, and public health.

Selected Publications

  • Ortega Y.R., Sheehy R.R., Cama V.A., Oishi K.K., and Sterling C.R. 1991. Restriction fragment length polymorphism analysis of Cryptosporidium parvum isolates of bovine and human origin. Journal of Protozoology. 38(6):40S-41S.
  • Ortega Y.R., Sterling C.R., Gilman R.H., Cama V.A., and Diaz F. 1993. Cyclospora species: A new protozoan parasite of humans. New England Journal of Medicine. 328:1308-1312.
  • Yang Y.M., Ortega Y.R., Sterling C.R., and Adam R.D. 1994. Giardia lamblia trophozoites contain multiple alleles of a variant-specific surface protein gene with 105 base pair tandem repeats. Molecular and Biochemical Parasitology. 68:267-276.
  • Ortega Y.R., Gilman R.H., and Sterling C.R. 1994. A new coccidian parasite (Apicomplexa: Eimeriidae) from humans. Journal of Parasitology. 80(4):625-629
  • Ortega Y.R., Roxas C.R., Gilman R.H., Miller N.J., Cabrera L., Taquiri C., and Sterling C.R. 1997. Isolation of Cryptosporidium parvum and Cyclospora cayetanensis from vegetables collected in markets of an endemic region in Peru. The American Journal of Tropical Medicine and Hygiene. 57(6):683-686.
  • Ortega Y.R. Nagle R., Gilman R.H., Watanabe J., Miyagui J., Quispe H., Kanagusuku P., Roxas C., and Sterling C.R. 1997. Pathological and clinical findings in patients with cyclosporiasis and a description of intracellular parasite life cycle stages. Journal of Infectious Diseases. 176(6):1584-1589.
  • Cama R.I., Parashar U.D., Taylor D.N., Hickey T., Figueroa D., Ortega Y.R., Romero S., Perez J., Sterling C.R., Gentsch J.R., Gilman R.H., and Glass R.I. 1999. Enteropathogens and other factors associated with severe disease in children with acute watery diarrhea in Lima, Peru. The Journal of Infectious Diseases. 119:1139-1144.
  • Cegielski J.P., Ortega Y.R, McKee S., Madden J.F., Gaido L., Schwartz D.A., Manji K., Jorgensen A.F., Miller S.E., Pulipaka U.P., Msengi A.E., Mwakyusa D.H., Sterling C.R., and Reller L.B. 1999. Cryptosporidium, Enterocytozoon and Cyclospora infections in pediatric and adult patients with diarrhea in Tanzania. Clinical Infectious Diseases. 28:314-321.
  • Adam R.D., Ortega Y.R., Gilman R.H., and Sterling C.R. 2000. ITS1 variability in Cyclospora cayetanensis. Journal of Clinical Microbiology. 38(6):2339-2343.
  • Bern C., Ortega Y.R., Checkley W., Roberts J.M., Lescano A.G., Cabrera L., Verastegui M., Black R.E., Sterling C.R., and Gilman R.H. 2002. Epidemiologic differences between cyclosporiasis and cryptosporidiosis in a cohort of Peruvian children. Emerging Infectious Diseases. 8(6):581-585.
  • Sathyanarayanan L. and Ortega Y.R. 2004. Effects of pesticides on sporulation of Cyclospora cayetanensis and viability Cryptosporidium parvum. Journal of Food Protection. 67(5):1044-49.
  • Saavedra, G.M. and Ortega Y.R. 2004. Seroprevalence of Toxoplasma gondii in swine and cattle from slaughter houses in Lima, Peru and Georgia, United States of America. J. Parasitol. 90(4):902-4.
  • Sathyanarayanan, L. and Ortega, Y. R. 2006. Effects of temperature and different food matrices on sporulation and viability of Cyclospora cayetanensis. Journal of Parasitology. 92: 218-222.
  • Cama V., Gilman, R. H., Vivar, A, Ticona, A., Ortega, Y., Bern C., and Xiao, L. 2006. Frequent mixed Cryptosporidium infections and HIV. Emerging Infectious Diseases. 12:1025-1028.
  • Ortega, Y.R. and Liao, J. 2006. Efficacy of microwave heating to inactivate Cyclospora cayetanensis and Cryptosporidium parvum oocysts. Journal of Food Protection. 68:1957-1960.
  • Feng, Y., Ortega, Y., He, G., Das, P., Zhang, X., Fayer, R., Gatei, W., Cama, V., and Xiao, L. 2007. The wide occurrence of Cryptosporidium bovis and the deer-like genotype in bovines. Veterinary Parasitology. 144:1-9.
  • Ortega, Y., Torres, P., and Mena, K. 2007. Determination of the prevalence of Neospora in dairy cattle using milk. Veterinary Parasitology. 144:353-5.
  • Ortega, Y.R., Torres, M.P., Van Excel, S., Moss, L. and Cama, V. 2007.Efficacy of disinfectants and sanitizers on viability of Encephalitozoon intestinalis. Journal of Food Protection. 70:681-684.
  • Cama V., Ross J., Crawford S., Kawai V., Chavez-Valdez R., Vargas D., Vivar A., Ticona E., Ñavincopa M., Williamson J., Ortega Y.R., Gilman R.H., Bern C., and Xiao L. 2007. Difference sin clinical manifestations among Cryptosporidium species and subtypes in HIV-infected persons. The Journal of Infectious Diseases. 196:684-691.
  • Xiao, L., Cama, V.A., Cabrera, L., Ortega, Y.R., Pearson, J., and Gilman, R.H. 2007.Possible transmission of Cryptosporidium canis between children and a dog in a household. Journal of Clinical Microbiology. 45:2014-2016.
  • Cooper, M.A., Sterling, C.R., Gilman, R.H., Cama, V.A., Ortega, Y.R., and Adam, R. 2010. Molecular analysis of household transmission of Giardia lamblia in a region of high endemicity in Peru. Journal of Infectious Diseases. 202: 1713-1721.
  • Ortega, Y.R., Torres, M.P., and Tatum, J.M. 2011. Efficacy of levulinic acid/SDS antibacterial against Encephalitozoon intestinalis, Cryptosporidium parvum, and E. coli O157:H7. Journal for Food Protection. 74(1): 140-144.
  • Robertson, L.J., Sprong, H., Ortega, Y.R. van der Giessen, J.W.B., and Fayer R. 2013. Impacts of globalization on foodborne parasites. Trends in Parasitology. 30:37-52.
  • Orozco-Mosqueda, G., Martínez-Loya, O., Ortega, Y. 2014. Cyclospora cayetanensis in a pediatric hospital in Morelia, México. Journal of the American Society for Tropical Medicine and Hygiene. 91(3):537-540.
  • Doyle, M.P., Erickson, M.C., Alali, W., Cannon, J., Deng, X., Ortega, Y., Smith, M.A., and Zhao, T. 2015. Food Industry’s Current and Future Role in Preventing Microbial Foodborne Illness within the United States. Clinical Infectious Diseases. 61(2)252-259.