First Year Fellows

Chelsea Modlin, MD

Medical School:  Geisel School of Medicine at Dartmouth
Chelsea was raised splitting her time between Norwich, VT and Frankfort, MI. She followed the cold weather to Carleton College in Northfield, MN for her undergraduate degree and earned her MD from the Geisel School of Medicine at Dartmouth in Hanover, NH. She then moved south to complete her residency in internal medicine at Emory University in Atlanta, GA. Chelsea’s research interests include the intersection of global health ethics and infectious diseases with a focus on community engagement, health equity in HIV/TB outcomes, research capacity in low-income settings, and the ethical considerations of international academic collaborations. When not at work she enjoys getting outdoors for a hike, sail, or bike ride and investigating the city for the best brunch spot.


Diana Zhong, MD

Medical School:  University of Pittsburgh School of Medicine
Diana grew up in Maryland, studied Biochemistry at the University of Maryland, and earned her MD at the University of Pittsburgh School of Medicine. She did her internship at Washington University in St. Louis then moved to Seattle to complete residency at the University of Washington. She worked as an academic hospitalist at the University of Washington for two years before moving back to Maryland for Infectious Diseases fellowship. Her background includes work with tumor immunology at the National Cancer Institute, as well as the gut microbiome. Her current academic interests include public health, vaccinology, and medical education. Outside of work, she enjoys drawing, designing, writing, cooking & eating, playing & creating games, travel, hiking, and spending time with loved ones including her corgi puppy, Marzipan.


Danica Rockney, MD

Medical School:  University of Wisconsin School of Medicine and Public Health
Danica was born and raised in Black River Falls, Wisconsin. She went to both undergrad and medical school at the University of Wisconsin-Madison and is a Badger through and through. She then moved to Atlanta, GA where she completed her internal medicine residency and chief residency at Emory University prior to moving to Baltimore. Her research interests are in medical education and clinically she is interested in HIV and underserved populations. When not in the hospital, she enjoys cooking, hiking, traveling, and cheering on all the Wisconsin sports teams.


Jerald Cherian, MD

Medical School:  State University of New York Downstate Medical Center
Jerald grew up in Yonkers, NY, a suburb of New York City.  For undergrad Jerald moved to Brooklyn as part of combined BA/MD program at CUNY Brooklyn College.  He subsequently obtained his MD from SUNY Downstate College of Medicine.  Jerald then moved down south to complete his residency training in Internal Medicine at Vanderbilt University Medical Center.  Jerald’s academic interests include transplant/oncology infectious diseases, as well as, informatics.  Outside of work, his interests include traveling, hiking, basketball, and baking.


Second Year Fellows

Styliani Karanika, MD

Medical School:  University of Athens
Stela grew up in Athens, Greece and studied medicine in the University of Athens. She served as a rural physician in south Crete for one year after her graduation and then worked as a resident in Athens for another year. Next, she joined MD Anderson Cancer Center at the University of Texas as a post-doctoral research fellow. There, she led projects on novel therapeutic approaches for metastatic prostate cancer focused mainly on the DNA damage response, activation of immune signaling and mechanisms of apoptosis in in-vitro and in-vivo models. She then moved to Brown University where she ran epidemiologic studies on C. difficile, MRSA and ESBL gram negative bacteria and was involved in clinical trials investigating novel diagnostic nanotechnology-based molecular assays for the diagnosis of bacteremia and candidemia. Following her research years, she completed her Internal Medicine Residency at Boston University Medical Center. Her current research focuses on novel therapeutic vaccination strategies for TB.  Mentors: Petros Karakousis, MD and Richard Markham, MD


Walid El-Nahal, MD

Medical School:  University of Virginia School of Medicine
Walid was born in Maryland, living in Bowie for the first eight years of his life. He then moved to Cairo, Egypt, where his family is originally from. After ten years there he moved back to the US to begin his undergraduate years at The University of Virginia, where he majored in chemical engineering. He spent twelve years there, completing his undergraduate degree, medical school, and residency at the UVA Health System’s Internal Medicine program. His clinical interests include both HIV and transplant, while his research interests lie in healthcare delivery and how differences in how care is delivered as well as differences in policy impact outcomes for patients with infectious diseases. He is currently working on a project to study the effect of the change from in-person visits to telemedicine during the pandemic on the care of people living with HIV.


Sonya Krishnan, MD

Medical School:  George Washington University
Sonya grew up in Minnesota and obtained her BA in Biology from Carleton College in Minnesota. After college she spent a two years at the NIH studying predictors of IRIS as well as inflammatory markers in Elite Controllers with Dr. Irini Sereti. She then completed her MD at George Washington University and subsequently moved to Baltimore for internal medicine residency at the JHH Osler Medical Training Program. For fellowship research she is working with Dr. Amita Gupta studying host biomarkers of HIV/TB and TB outcomes with particular interest in understanding inflammation pathways, their impacts, and potential therapies. During the 2020-2021 academic year she will also be pursing additional training via the Bloomberg School of Public Health’s Graduate Training Program In Clinical Investigation. Outside of work, she enjoys hiking with her husband and silky terrier as well as gardening.


L. Leigh Smith, MD

Medical School:  Howard University
Leigh grew up in Southern California and received her undergraduate degree from Brown University.  She then moved to DC and received her medical degree from Howard University College of Medicine and ultimately completed residence at Jackson Memorial/University of Miami in Miami, FL.  She spent the last year working as an academic hospitalist where she grew up in California at Loma Linda University Medical Center.  Her clinical interests include outbreak response, disaster & emergency preparedness as well as emerging infectious disease.  She enjoys hiking, running and trying new foods.


Third Year Fellows

Sara Karaba, MD PhD

Medical School: University of Maryland
Sara grew up in Maryland, and obtained her BS in Microbiology from the University of Maryland. She then continued her education at Northwestern University where she was part of the Medical Scientist Training Program, earning her MD and PhD. Her PhD research focused on type II protein secretion and recreated proteases in Stenotrophomonas maltophilia. She then moved to Baltimore and completed internal medicine residency in the Osler Medical Training Program at the Johns Hopkins Hospital. Current research interests include hospital epidemiology and antimicrobial stewardship, with a focus on multidrug-resistant Gram-negative bacteria.  Mentors:  Sara Cosgrove, MD and Pranita Tamma, MD


Saman Nematollahi, MD

Medical School: University of Arizona College of Medicine
Saman grew up in Tucson, Arizona. He completed his undergraduate study at the University of Arizona with dual degrees in Physiology and Spanish Literature. He spent some time after undergrad working in a neuroscience lab before starting medical school at the University of Arizona. He then moved to NYC where he completed residency at Columbia University. He is currently obtaining a Master of Education in the Health Professions at Johns Hopkins. His clinical interests include management of immunocompromised hosts and fungal infections, and his research interests include medical education and fungal infections. His current research project involves a multi-center Twitter-based curriculum on identification of risk factors of invasive fungal infections and test characteristics of serum beta-d-glucan and galactomannan. He loves to play soccer with his wife and son.  Mentor: Michael Melia, MD and Robin Avery, MD


Jessica Queen, MD, PhD

Medical School: Northwestern University
Jessica grew up in Maryland in southern Anne Arundel County. She obtained her BS in Biochemistry at Simmons College in Boston. After college, she spent a year conducting research at the NIH through the post-baccalaureate I.R.T.A program. She then pursued her MD/PhD at Northwestern University in Chicago, where she conducted her thesis research in the lab of Dr. Karla Satchell on the interplay of secreted toxins of Vibrio cholerae with the innate immune system. She then completed her residency in Internal Medicine at Weill Cornell – New York Presbyterian Hospital. Her academic interests include bacterial pathogenesis, host-pathogen interactions, and mentorship of underrepresented communities in medicine and science. Her postdoctoral research in the Sears lab centers on the pathogenicity and carcinogenic potential of Fusobacterium nucleatum in the colon.  Mentors: Cynthia Sears, MD


Nicole Skinner, MD, PhD

Medical School: University of Minnesota Medical School
Nicole grew up in northern Virginia, just outside of Washington, DC. After obtaining her BA in neuroscience from the University of Virginia, she became interested in immunology and spent a year as an NIH post-baccalaureate fellow working on graft-versus-host disease. She then moved to Minneapolis/St. Paul and entered the University of Minnesota MD/PhD program, earning her PhD in immunology studying CD8+ T cell responses to DNA vaccines. Following the MD/PhD program, she completed her Internal Medicine residency at Beth Israel Deaconess Medical Center in Boston. Her current research interests involve characterization of adaptive immune responses to infection in humans.  Mentors:  Justin Bailey, MD, PhD and Stuart Ray, MD

Fourth Year Fellows

Elisa Ignatius, MD, MSc

Medical School:  Emory University School of Medicine
Elisa grew up in Washington, DC and obtained her BA in History from Columbia University. She then worked for an NGO in Rwanda before starting medical school at Emory University. During medical school, she also earned a Master’s of Science in the Control of Infectious Diseases from the London School of Hygiene and Tropical Medicine. Her thesis research focused on Extensively Drug Resistant (XDR) TB in South Africa, working with Dr. Keertan Dheda. She then returned to Atlanta to finish medical school and remained at Emory for her Internal Medicine residency. After residency, she worked as a co-investigator with Dr. Carlos del Rio on two HIV prevention clinical trials. Her research interests include the clinical pharmacology of TB diagnostics and therapeutics as well as care delivery systems.  Mentors: Kelly Dooley, MD, MPH, PhD ,


Andrew Karaba, MD, PhD

Medical School:  Northwestern University
Andrew grew up in Clarendon Hills, IL just outside of Chicago. He earned a BA from Northwestern University in Evanston, IL where he was in the Integrated Science Program and studied biology and chemistry. After college, he continued his education at Northwestern in the Medical Scientist Training Program where he obtained an MD and PhD. His PhD research centered on Herpes simplex virus pathogenesis in the laboratory of Richard Longnecker, PhD. He then moved to Baltimore, MD where he completed internal medicine residency in the Osler Medical Training Program. Andrew is in the ABIM research pathway. His current research focuses on the innate immune response to viral infections.  Mentor: Andrea Cox, MD, PhD


William Werbel, MD

Medical School:  University of Michigan School of Medicine
Bill grew up in the New York suburbs, staying on the East Coast for college at Harvard, where he studied evolutionary biology and biomechanics. He then moved to the Midwest for medical school at the University of Michigan before beginning residency at Northwestern where he also served as chief medical resident. His academic interests include risk stratification and prevention of opportunistic infections in the immune compromised host, with a focus on transplant and oncology patients. He is enrolled in the Graduate Training Program in Clinical Investigation and is engaged in research with Dr. Christine Durand and the Epidemiologic Research Group in Organ Transplantation. Current research efforts include characterizing infection outcomes in HIV+ transplant patients. Personal interests outside of medicine include distance running and music composition.  Mentor: Christine Durand, MD