Research topics

• Molecular Epidemiology
• Intestinal immune response 

Lines of research

• Molecular Epidemiology of enteropathogens, uropathogens and mycobacteria in patients and environmental samples.


• Identification of Biomarkers that will allow us to distinguish between patients that have viral and bacterial diarrhoea. As well as to identify biomarkers of diarrhoea severity, before this outcome in order to send these patients to the emergency room for proper preventive treatment.


• Development of molecular diagnostic methods for human pathogens


• Murine models of infection with different enterobacteria.


• Intestinal immune response against diarrheagenic Escherichia coli.


• Molecular Epidemiology of patients with Diabetes Mellitus type 2 and acute myocardial infarction.

Brief description of the work in my laboratory

1. Large epidemiological studies of pathogens associated with diarrhoea illness and urinary tract infections in patients requiring hospitalization and community acquired infection.


2. Molecular epidemiological studies of pathogens isolated from street-vended food and beverages


3. Development of molecular diagnostic methods for human pathogens using techniques of molecular biology that should be specific, sensitive, quick and of low cost. In order to implement then in the national health services.


4. Evaluation of the immune response induced in vivo and in situ antes after la infection with a bacteria that cause diarrhoea in humans and a murine enteropathogen using wild type knock out mice, by ELISA, immunohistochemistry and RT-PCR techniques


5. Evaluation of the immune response induced on human intestinal cell lines against the different Escherichia coli diarrheagenic groups by FACS.


6. Determination, evaluation y comparison of the presence of single nucleotide polymorphisms and haplotypes fro different genes in control subjects and patients with Diabetes Mellitus type 2 and acute myocardial infarction.

Description of recent work

We have done several molecular epidemiological studies using the molecular diagnostic methods that we have developed. That have allows to establish the prevalence of different diarrheagenic E. coli groups (DEC) and also of Norovirus in patients with acute diarrhoea requiring hospitalization in several regions of our country. This has allow us to demonstrate that DECs are the main agents causing bacterial acute diarrhoea in children under five year of age, requiring hospitalization, in Mexico. We have also demonstrated that Norovirus is an important agent of diarrhoea illness in children of this age group. On the other hand, we have also established that DECs are the main agents causing bacterial acute diarrhoea in slums of Mexico City. My laboratory have also collaborated in establishing that the prevalence of Salmonella as an agent causing acute diarrhoea in children requiring hospitalization has diminished in Yucatán, whereas Shigella severe cases in this children has increased.

We have shown that DECS are the most frequent pathogens identified among street-vended food and beverages, as well as in salads sold in local restaurants.

We have developed a murine model of infection with enterotoxigenic Escherichia coli isolated from humans and with Citrobacter rodentium, using this model we have initiated the characterization of the immune response induced in vivo and in situ against these bacteria in wild type and  CD40 ligand KO mice.

We have also done molecular epidemiological studies of uropathogenic E. coli in both patients with acute infection and recurrent infection.

Until know we have characterized the distribution and prevalence of three SNPs of CD14, interleukin 6 and Leptin genes, in patients with Diabetes Mellitus type 2 and acute myocardial infarction

1. Patzi-Vargas S, Zaidi M, Bernal-Reynaga R, León-Cen M, Michel A, Estrada-Garcia T. Persistent Bloody Diarrhoea Without Fever Associated with Diffusely Adherent Escherichia coli in a Young Child. J Med Microbiol. 2013 Sep 11. doi: 10.1099/jmm.0.062349-0. [Epub ahead of print]


2. Bernal-Reynaga R, Thompson-Bonilla R, Lopez-Saucedo C, Pech-Armenta M, Estrada-Parra S, Estrada-Garcia T. C57-CD40 ligand deficient mice: a potential model for enterotoxigenic Escherichia coli (H10407) colonization. Vet Immunol Immunopathol. 2013 Mar 15;152(1-2):50-6.doi:10.1016/j.vetimm.2012.09.025. PMID: 23098671.


3. Zaidi MB, Estrada-García T, Campos FD, Chim R, Arjona F, Leon M, Michell A, Chaussabel D. Incidence, clinical presentation, and antimicrobial resistance trends in Salmonella and Shigella infections from children in Yucatan, Mexico. Front Microbiol. 2013 Oct 1;4:288. doi: 10.3389/fmicb.2013.00288.


4. Estrada-Garcia T, Navarro-Garcia F. Enteroaggregative Escherichia coli pathotype: a genetically heterogeneous emerging foodborne enteropathogen. FEMS Immunol Med Microbiol. 2012 Dec;66(3):281-98. doi: 10.1111/j.1574-695X.2012.01008.x. Review. PMID: 22775224.


5. López-Hernández D, Meaney-Martínez A, Sánchez-Hernández OE, Rodríguez-Arellano E, Beltrán-Lagunes L, Estrada-García T. Diagnostic criteria for hypoalphalipoproteinemia and the threshold associated with cardiovascular protection in a Mexican Mestizo population. Med Clin (Barc). 2012 May 12;138(13):551-6. doi: 10.1016/j.medcli.2011.09.037. Spanish. 


6. Zaidi MB, McDermott PF, Campos FD, Chim R, Leon M, Vazquez G, Figueroa G, Lopez E, Contreras J, Estrada-Garcia T. Antimicrobial-resistant Campylobacter in the food chain in Mexico. Foodborne Pathog Dis. 2012 Sep;9(9):841-7. doi: 10.1089/fpd.2012.1127. Epub 2012 Aug 7.


7. Castro-Rosas J, Cerna-Cortés JF, Méndez-Reyes E, Lopez-Hernandez D, Gómez-Aldapa CA, Estrada-Garcia T. Presence of faecal coliforms, Escherichia coli and diarrheagenic E. coli pathotypes in ready-to-eat salads, from an area where crops are irrigated with untreated sewage water. Int J Food Microbiol. 2012 May 15;156(2):176-80. doi: 10.1016/j.ijfoodmicro.2012.03.025. PMID: 2250762PMID: 22401724 [PubMed - indexed for MEDLINE]


8. Cerna-Cortes JF, Vega-Negrete W, Ortega-Villegas MA, Zaidi MB, Estrada-Garcia T. Consumption of street-vended beverage a potential exposure risk for non-O157 enterohemorrhagic Escherichia coli infection: the importance of testing for virulence loci. Clin Infect Dis. 2012 Jan 1;54(1):154-5. doi:10.1093/cid/cir778. 


9. Fernandez-Rendon E, Cerna-Cortes JF, Ramirez-Medina MA, Helguera-Repetto AC, Rivera-Gutierrez S, Estrada-Garcia T, Gonzalez-Y-Merchand JA. Mycobacterium mucogenicum and other non-tuberculous mycobacteria in potable water of a trauma hospital: a potential source for human infection. J Hosp Infect. 2012 Jan;80(1):74-6. doi: 10.1016/j.jhin.2011.10.003.

1. Long KZ, Santos JI, Rosado JL, Estrada-García T, Haas M, Al Mamun A, Dupont HL, Nanthakumar NN. Vitamin A supplementation modifies the association between mucosal innate and adaptive immune responses and resolution of enteric pathogen infections. Am J Clin Nutr; 2011 93(3):578-85. Epub 2011 Jan 19.


2. Lozano-Nuevo JJ, Estrada-García T, Vargas-Robles H, Escalante-Acosta BA, Rubio-Guerra AF. Correlation between circulating adhesion molecules and resistin levels in hypertensive type-2 diabetic patients. Inflamm Allergy Drug Targets; 2011;10(1):27-31.


3. Gutiérrez-Escolano AL, Velázquez FR, Escobar-Herrera J, López Saucedo C, Torres J, Estrada-García T. Human caliciviruses detected in Mexican children admitted to hospital during 1998-2000, with severe acute gastroenteritis not due to other enteropathogens. J Medi Virol 2010 82:632-637.


4. Lopez-Saucedo C, Cerna JF, Estrada-García T. Non–O157 Shiga Toxin–Producing Escherichia coli is the Most Prevalent Diarrheagenic E. coli Pathotype in Street-Vended Taco Dressings in Mexico City. Clin Infec Dis 2010; 50:450-451.


5. Long KZ, Rosado JL, Santos JI, Haas M, Al Mamun A, DuPont HL, Nanthakumar NN, Estrada-García T. Associations between mucosal innate and adaptive immune responses and resolution of diarrheal pathogen infections. Infect Immun. 2010 Mar;78(3):1221-8.


6. Cerna-Cortés JF, Estrada-García T, González-y-Merchand JA. Isolation of Mycobacterium mucogenicum from street-vended chili Sauces: a potential source of human infection. J Food Protection 2009; 72:182-184.


7. Estrada-García T, Lopez-Saucedo C, Thompson-Bonilla R, Abonce M, Lopez-Hernandez D, Santos JI, Rosado JL, DuPont H L, Long KZ. Association Diarrheagenic Escherichia coli Pathotypes association with Infection and Diarrhea among Mexican Children: Atypical Enteropathogenic E. coli is Associated with Acute Diarrhea. J Clin Microbiol 2009; 47:93-98


8. Pérez-Martínez I, Ponce-De-León A, Bobadilla M, Villegas-Sepulveda N, Pérez-García M, Sifuentes-Osornio J, González-y-Merchand JA, Estrada-García T. A novel identification scheme for: genus Mycobacterium, M. tuberculosis Complex and seven mycobacteria species of human clinical impact. Eur J Clin Microbiol Infec Dis 2008; 27:451-459


9. Zaidi M B, Calva J J, Estrada-García M T, Leon V, Vazquez G, Figueroa G, Lopez E, Contreras J, Abbott J, Zhao S, McDermott P, Tollefson. Integrated food chain surveillance system for Salmonella in Mexico: a model for developing countries” Integrated Food Chain Surveillance System for Salmonella spp. in México. Emerg Infect Dis 2008; 14:429-435


10. Long KZ, Santos JI, Rosado JL, Lopez-Saucedo C, Thompson-Bonilla R, Abonce M, DuPont HL, Hertzmark E, Estrada-García T. Impact of Vitamin A on selected gastrointestinal pathogen infections and associated diarrheal episodes among children in Mexico City, Mexico. J Infect Dis 2006;194:1217-25.


11. Rodriguez-Pastrana AF, Lopez-Saucedo C, Salazar-Exaire D, Estrada-Garcia T.
    Patient’s UPEC isolates fim+/pap- only correlated with low UTI whereas pyelonephritis isolates were fim+/pap+. Kidney Int. 2007 72(10):1289. PubMed PMID: 17972910


12. Pacheco-Gil L, Ochoa TJ, Flores-Romo L, DuPont HL, Estrada-García T. Enteroinvasive Escherichia coli severe dysentery complicated by rotavirus gastroenteritis. J Infection 2006; 53:e211-e213.


13. Estrada-Garcia T, JF Cerna JF, L Pacheco-Gil L, F R Velazquez, T Ochoa, J Torres HL DuPont. Drug resistance Escherichia coli Mexico. Emer Infect Dis 2005; 11:1306-1308.


14. Flores-Langarica A, Meza-Perez S, Calderon-Amador J, Estrada-García T, Mac Pherson G, Lebecque S, Saeland S, Steinman R M, Flores-Romo L. Network of dendritic cells within the muscular layer of the mouse intestine. PNAS 2005;102:19039-19044.


15. Estrada-García T, Lopez-Saucedo C, Arevalo C, Flores-Romo L, Luna O, and Perez-Martinez I. Street-vended seafood: a risk for foodborne diseases in Mexico. Lancet Infect Dis 2005;5:69-70.


16. Lopez-Saucedo C, Cerna JF, Villegas-Sepúlveda N, Thompson R, Velásquez FR, Torres J, Tarr PI, Estrada-García T. Single multiplex polymerase chain reaction to detect diverse loci associated with diarrheagenic Escherichia coli. Emer Infect. Dis 2003; 9:127-131


17. Estrada-García T, Cerna JF, Thompson MR, López-Saucedo C. Feacal contamination and enterotoxigenic Escherichia coli in street-vended chili sauces in Mexico and its public health relevance. Epidemiol. Infect. 2002; 129:223-226

• Beyanora Research Institute, Seattle, Washington, US
• University of Texas, Houston, Texas, US
• University of Queensland, Herston, Queensland, Australia
• Health ministry of the state of Yucatan and Tabasco
• Instituto de Seguridad y Servicios Social de los trabajadores del Estado (ISSSTE), DF
• National school of Biological Sciences-IPN

• Dr. Herbert DuPont St. Luke’s Episcopal Hospital, Baylor College of Medicine Houston y School of Public Health, University of Texas, Houston
• Dr. Kurt Long, School of Population Health, University of Queensland, Herston, Dr. Kurt Long, School of Population Health, University of Queensland, Herston, Queensland, Australia
• Dra. Mussaret Zaidi, Hospital O’ Horán, Secretaria de Salud del Estado de Yucatán
• Dra. Leova Pacheco, Hospital del Niño, Secretaria de Salud del Estado de Tabasco

Adscription of alumini

• Jorge Francisco Cerna Cortés, Research Associate, ENCB, IPN, DF, Mexico
• Laura Leticia Flores Ibarra, Research Assistant, University of California, San Francisco, US
• Osvaldo Sanchez, Faculty of Medicine, Universidad Metropolitana, Mexico
• Alejandra Meaney Martínez, BioRad, ISSSTE, DF, Mexico
• José Juan Lozano Nuevo, Hospital Ticomán, SS. DF, Mexico
• Martha Eunice Rodríguez Arellano, ISSSTE, DF, Mexico