Meet Our Team
We are a multidisciplinary group of scientists and veterinarians advancing human and wildlife health through field-based and academic work across East-Central Africa, Southeast Asia and California. Our work focuses on understanding disease dynamics between wildlife, people, and the environments they share.
The People Behind the Work
Learn more about our international and local team that drive our research.
Tierra Smiley Evans
Principal Investigator
Dr. Tierra Smiley Evans is an infectious disease epidemiologist and wildlife veterinarian who investigates how anthropogenic forest change and biodiversity loss alter the ecology and evolution of zoonotic viruses. Her research utilizes a transdisciplinary One Health approach to examine the mechanisms of human disease emergence at the forest edge, with a specific focus on how nonhuman primates facilitate spillover. A central component of her current work involves analyzing human and great ape immune responses within shared high-risk landscapes to identify biological mechanisms of disease resistance and resilience. She leads an international research program at UC Berkeley and serves as the Chief Veterinary and Scientific Officer for Gorilla Doctors, where she oversees the scientific strategy and veterinary care for endangered eastern gorillas in Uganda, Rwanda, and the DRC. Her background includes over 15 years of longitudinal field studies with remote communities, such as nomadic elephant loggers in Myanmar and the Batwa in Uganda. Her work has been recognized with honors including a Fulbright Fellowship and the NIH/Fogarty International Research Scientist Development Award.
Sonia Ghose
Postdoctoral Scholar and Laboratory Manager
Dr. Ghose’s path to the Smiley Lab is driven by her passion for understanding how microbiomes influence wildlife health and conservation. She earned her BA in Biology from Occidental College and her PhD in Population Biology from the University of California, Davis, where she trained in the National Institutes of Health’s Animal Models of Infectious Diseases Training Program. Prior to graduate school, she worked as a research intern at La Selva Biological Station in Costa Rica and as a molecular laboratory technician at the California Academy of Sciences. Her research interests include microbial ecology, host-microbiome interactions, infectious disease, and conservation biology. For her dissertation, she studied the skin-associated microbiome of the endangered Sierra Nevada yellow-legged frog threatened by the chytrid fungal pathogen Batrachochytrium dendrobatidis. Dr. Ghose joined the Smiley Lab as a postdoctoral scholar in June 2025. Her current research focuses on the gut microbiome of endangered eastern gorillas and how human impacts, disease, and clinical interventions influence microbial communities and antimicrobial resistance.
Reinaldo Mercado-Hernandez
Postdoctoral Scholar
Reinaldo is an immunologist whose research integrates epidemiology, biostatistics, and infectious disease. He earned his BS in Microbiology from Ana G. Méndez University in Carolina, Puerto Rico, where he began his multidisciplinary training studying how the immune system regulates organ regeneration in sea cucumbers. He then spent two years at the National Institute of Allergy and Infectious Diseases’ Rocky Mountain Laboratories in Hamilton, Montana, supporting preclinical vaccine studies for multiple viruses. He recently completed his PhD in Infectious Diseases and Immunity at the University of California, Berkeley, where he further developed his epidemiological, biostatistical, and computational skills. Using data and biological samples from a pediatric cohort, his dissertation examined the association between obesity and an increased risk of dengue virus infection and disease, as well as distinct antibody responses in children with obesity. As a postdoctoral scholar in the Smiley laboratory, Reinaldo investigates the epidemiological risk of wildlife exposure to sarbecoviruses, leads capacity building for the laboratory serology and tissue culture sections, and collaborates with partners in Rwanda to develop an eastern gorilla cell line.
Ian Pshea-Smith
Postdoctoral Scholar
Ian is a global health epidemiologist with training in medical geography and disease ecology. They are originally from the Great Lakes region of the USA, and completed a Bachelor’s degree in International Health at Bethel University (IN) and a MPH in Global Health Epidemiology at the University of Michigan before completing a doctoral degree in Medical Geography and Global Health at the University of Florida. They are interested in global health research, especially community-driven and applied public health. Ian’s dissertation work described the community ecology, distribution patterns, and population risk dynamics of mosquitoes and ticks in the countries of Haiti and Georgia. Ian joined the Smiley lab in 2026 focusing on a One Health arbovirus project in Uganda.
Maya Homsy King
PhD Student UC Berkeley
Maya grew up in Kampala, Uganda where she first became interested in One Health through an internship observing the Ebola virus outbreak response. To Maya, One Health is a way to use multidisciplinary science to develop mutually beneficial relationships between humans, animals and the environment we share. She received her bachelor's degree from University College Utrecht, and her Master's in Public Health from the University of California, Berkeley in 2023, where she did her capstone at Bwindi Impenetrable National Park in Uganda investigating employee health at wild great ape sites. This work furthered her interest in zoonotic disease transmission and community-driven research. She then worked for the Wildlife Conservation Society’s Arctic Beringia program, doing research on community-based surveillance for zoonotic diseases in rural Alaska, before coming back to UC Berkeley to pursue a PhD in Environmental Health Sciences. Her work now focuses on using the Spatial Monitoring and Reporting Tool (SMART) to integrate ranger-reported observations of gorilla health across Uganda, Rwanda and the DRC.
John Kayiwa
PhD Student UC Berkeley
John Timothy Kayiwa is a microbiology researcher with experience in public health surveillance and diagnostics, focusing on influenza, SARS-CoV-2, arboviruses (including yellow fever, dengue, West Nile, chikungunya, onyong nyong, and Zika), and viral hemorrhagic fevers. His work is grounded in a One Health framework, including research on bat viral ecology in Uganda and collaborative projects within the EEIDI/CREID Network investigating zoonotic spillover at the source in wildlife and indigenous rural communities. John has a strong laboratory background in serology, neutralization assays, molecular diagnostics (PCR and sequencing), cell and virus culture, and IFA microscopy, and has contributed to peer-reviewed publications. His work has been recognized with honors including the CDC and ATSDR Outbreak Response Team Award (2016) and the Heroes in Health Award – Allied Health Worker of the Year (2020). He is currently a PhD student in Infectious Diseases and Immunity at the UC Berkeley School of Public Health. His professional goals focus on disease prevention, outbreak control, surveillance, and population-level health improvement.
Julia Lippert
PhD Student UC Berkeley
Julia earned her bachelor’s degree from Seattle Pacific University and later obtained a Master of Public Health and Tropical Medicine from Tulane University. She spent nearly two years based in the Bwindi Impenetrable Forest in Uganda, where she managed the Bwindi mHealth project. Julia is currently a PhD student in the Integrative Biology Department at the University of California, Berkeley. Her doctoral work is guided by One Health principles and focuses on disease dynamics at the human-animal interface. She has a strong interest in public health communication and healthcare delivery, with a broader passion for applying One Health approaches to improve health outcomes across human and animal populations.
Tatiana Henry
PhD Student UC Davis
Dr. Tatiana Henry is a veterinarian with interests in emerging zoonotic infectious disease, wildlife conservation, and One Health. She received her DVM from the Cummings School of Veterinary Medicine at Tufts University, along with an International Veterinary Medicine Post-Graduate Certificate. As a veterinary student, she developed an interest in wildlife epidemiology through field research with free-ranging nonhuman primates in Peru. Following post-graduate clinical training in small animal, avian, and exotic animal medicine and surgery, Tatiana completed a Masters in Preventive Veterinary Medicine (MPVM) at UC Davis in 2024, where she conducted arbovirus serosurveillance research in nonhuman primates in collaboration with the One Health Institute and the CREID EpiCenter for Emerging Infectious Disease Intelligence. Her work in the Smiley Evans Lab, in partnership with Gorilla Doctors, focuses on risk assessment and wildlife surveillance for viral zoonoses of public health concern and pandemic potential in the Greater Virunga Landscape. She is passionate about detecting, modeling, and mitigating infectious disease risks at human-wildlife interfaces, with a particular interest in zoonoses circulating in nonhuman primates that threaten both wildlife and human health.
Jennifer Yu
PhD Student UC Davis
Dr. Yu obtained her DVM from UC Davis and an MS in conservation medicine from Tufts. She completed a post-graduate internship with the Smithsonian’s National Zoo & Conservation Biology Institute’s Global Health Program, where she contributed to international conservation and One Health projects and gained experience in research and project management. She also completed an internship with the Wildlife Center of Virginia, where she strengthened her clinical background in wildlife rehabilitation medicine. Dr. Yu is currently a PhD student in Epidemiology at UC Davis, applying epidemiologic modeling approaches to her study system: elephant endotheliotropic herpesvirus (EEHV). She also serves as a project manager for the Wildlife Health Information System — an electronic medical record database for wildlife populations — with the Veterinary Initiative for Endangered Wildlife (VIEW). Her research interests include identifying social and other risk factors for infectious disease transmission and using population-level approaches to support evidence-based medicine and wildlife management.
Varnika Dhandapani
Undergraduate Honors Student UC Berkeley
Varnika Dhandapani is an undergraduate student in the senior year completing her degree in Molecular Environmental Biology. She previously worked at UCSF as a research intern in the Program for Reproductive Health and the Environment conducting systematic reviews of studies analyzing the impact of environmental toxins such as BACs and ddACs on reproductive health, and then at the Robinson Lab assisting with cell cultures and RNA purification. Her research interests are in bacterial symbionts and zoonotic diseases. She joined the Smiley Evans Lab in 2025 to conduct research for her senior year thesis, studying the spread of antimicrobial resistance genes in gorilla gut microbiomes.
Rane Dragovich
Laboratory Assistant
Rane Dragovich completed her Bachelor of Science degree in Public Health - Global Health at the University of Washington, where she worked as a research technician in a molecular biology laboratory on developing rapid, accessible, and noninvasive techniques for Tuberculosis diagnosis. During this time, she discovered the One Health approach to scientific research, as well as continued to foster her interest in emerging zoonotic diseases. Rane went on to achieve her Masters of Public Health at the University of California, Berkeley focusing on Infectious Diseases and Vaccinology in May of 2025. Here, she has continued to work as a lab assistant in the Smiley lab, primarily managing the Gorilla Doctors Biobank and learning more about zoonotic disease surveillance and prevention.
David Wolking
Global Operations Manager
David joined the Smiley Lab in 2025 after years of collaboration with Dr. Smiley Evans and Gorilla Doctors, a partnership that began in 2009 as a founding member of the UC Davis One Health Institute. He managed the USAID PREDICT project for over a decade and later served as Technical Director for the USAID-funded One Health Workforce Next Generation project, while also contributing to the CEPI-funded Virus Intelligence & Strategic Threat Assessment (VISTA) initiative. In his current role with UC Berkeley and Gorilla Doctors, David supports project management, mentorship, monitoring and evaluation, and communications for major global initiatives, including the World Bank Pandemic Fund’s Greater Virunga Landscape project and a Wellcome Trust–funded dengue and Zika research collaboration. He holds an MS in International Development from UC Davis and works to build cross-university partnerships advancing One Health, public health, and conservation.
Alex Tremeau-Bravard
Senior Research Associate
Alexandre Tremeau-Bravard joined Gorilla Doctors as a laboratory specialist in 2023. Alex is responsible for supporting Gorilla Doctors laboratory activities in Rwanda, Uganda, and eastern DR Congo. Alex earned a Bachelor of Science in Biochemistry from the University of Burgundy in Dijon, France, and a master’s and PhD of Molecular and Cellular Biology from the University of Strasbourg, France. After a postdoctoral position at the University of California, Davis working on the mechanisms of transcription and DNA repair, he began his journey as a diagnostician after volunteering in an HIV clinic in Nigeria for a year helping the patients assess their HIV viral loads. Alex now serves as a Staff Research Associate in the One Health Institute Laboratory at the University of California, Davis supporting both local and international research projects, including travel across Africa to work on diagnostic of infectious diseases.
Benard Ssebide
PhD Student Makerere University
NEEDS REPLACED -- Alexandre Tremeau-Bravard joined Gorilla Doctors as a laboratory specialist in 2023. Alex is responsible for supporting Gorilla Doctors laboratory activities in Rwanda, Uganda, and eastern DR Congo. Alex earned a Bachelor of Science in Biochemistry from the University of Burgundy in Dijon, France, and a master’s and PhD of Molecular and Cellular Biology from the University of Strasbourg, France. After a postdoctoral position at the University of California, Davis working on the mechanisms of transcription and DNA repair, he began his journey as a diagnostician after volunteering in an HIV clinic in Nigeria for a year helping the patients assess their HIV viral loads. Alex now serves as a Staff Research Associate in the One Health Institute Laboratory at the University of California, Davis supporting both local and international research projects, including travel across Africa to work on diagnostic of infectious diseases.
Eddy Syaluha
PhD Student Makerere University
Dr. Eddy Syaluha is a National Geographic Explorer implementing non-invasive health monitoring of unhabituated, critically endangered Grauer’s gorillas across the Kahuzi-Biega, Maiko, Itombwe, and Tayna landscapes of eastern Democratic Republic of Congo. He serves as Head Veterinarian for Gorilla Doctors in the DRC and has been with the organization since 2004, when he began as a Field Veterinarian. Over his career, he has led and supported numerous eastern gorilla interventions and held primary responsibility for their medical care.
Dr. Syaluha earned his veterinary degree from the Catholic University of Graben in Butembo, DRC, in 2002, and completed a Master’s degree in Wildlife Health and Management at Makerere University in Uganda in 2019. His research examined diet selection strategies and exposure to hepatotoxic phytochemicals in Grauer’s gorillas in Mount Tshiabirimu Forest, Virunga National Park.
He is currently enrolled in a hybrid PhD program at Makerere University and the University of California, Berkeley, focusing on gut microbiome, diet, and stress profiles of habituated Grauer’s gorillas in the DRC.
Jean Claude Tumushime
PhD Student Makerere University
Jean Claude Tumushime is a wildlife health scientist focused on emerging infectious diseases at the human–wildlife interface. He trained as a veterinarian at the University of Rwanda, School of Veterinary Medicine. In 2014, he completed a year-long internship with Gorilla Doctors in Rwanda, concentrating on gorilla medicine, and joined the organization full-time in 2015. He served as a laboratory technician and field veterinarian for the USAID Emerging Pandemic Threats–PREDICT project, participating in wildlife surveillance involving bats, rodents, and non-human primates and the detection of novel viruses of public health concern.
He also contributed to establishing the first Gorilla Doctors wildlife laboratory in Rwanda and worked under the guidance of Drs. Tierra Smiley Evans and Alexandre Tremeau-Bravard to validate diagnostic assays for infectious diseases affecting mountain gorillas. Jean Claude holds an MSc in Wildlife Health and Management from Makerere University, Uganda, and is currently enrolled in a hybrid PhD program at Makerere University and the University of California, Berkeley. His doctoral research focuses on identifying and molecularly characterizing respiratory pathogens in mountain gorillas and assessing their transmission dynamics.
Nelson Bukamba
PhD Student Makerere University
Dr. Bukamba Nelson is dedicated to advancing wildlife health through a One Health approach, addressing challenges posed by emerging infectious and zoonotic diseases. His hands-on work with Gorilla Doctors spans multiple projects, including the Epicentre for Emerging Infectious Disease Intelligence (EEIDI), a collaboration with the UC Davis One Health Institute focused on studying the early stages of zoonotic disease emergence in southwest Uganda. In this role, he was actively involved in wildlife disease surveillance efforts.
Dr. Nelson holds a Master’s degree in Conservation Medicine from the University of Edinburgh, where he explored innovative methods for detecting Strongyloides species in mountain gorillas, baboons, and free-roaming dogs living near Bwindi Impenetrable National Park.
He is currently pursuing a hybrid PhD at Makerere University and the University of California, Berkeley with the Smiley Lab, investigating the epidemiology of Zika virus and examining how non-human primate epizootic cycles influence its spread across Uganda.
Nahabwe Haven
Master’s Student UC Berkeley Public Health Online
Nahabwe Haven is a public health specialist with over a decade of experience working in rural southwestern Uganda, including extensive work with Bwindi Community Hospital. He holds a Bachelor of Science in Community Health and a Master of Public Health, with a focus on community-based and One Health research. His work has included leading and supporting studies on infectious diseases, zoonotic spillover, modern contraception uptake, and health systems strengthening in rural and Indigenous communities, including the Batwa people. Haven has served as a Lead Researcher on multiple National Institutes of Health–funded projects, including the Epicenter for Emerging Infectious Disease Intelligence (EEIDI) and the Bwindi mHealth project through UC Davis.
Beginning in 2025, he joined The Pandemic Fund’s One Health initiative in the Greater Virunga Landscape, where he leads human zoonotic spillover surveillance in communities surrounding Bwindi Impenetrable National Park. He is currently pursuing graduate training in epidemiology and biostatistics at UC Berkeley.
Our Research Projects
The Smiley Lab explores how global forest change reshapes ecosystems and how those changes influence the emergence of infectious disease, with the goal of informing smarter conservation, prevention, and global health strategies.
