Dr. Omer has conducted studies in the United States, Guatemala, Kenya, Uganda, Ethiopia, India, Pakistan, Bangladesh, South Africa, and Australia. Dr Omer’s research portfolio includes epidemiology of respiratory viruses such as influenza, RSV, and - more recently - COVID-19; clinical trials to estimate efficacy of maternal and/or infant influenza, pertussis, polio, measles and pneumococcal vaccines; and trials to evaluate drug regimens to reduce mother-to-child transmission of HIV. Moreover, he has conducted several studies on interventions to increase immunization coverage and acceptance. Dr Omer’s work has been cited in global and country-specific policy recommendations and has informed clinical practice and health legislation in several countries. He has directly mentored over 100 junior faculty, clinical and research post-doctoral fellows, and PhD and other graduate students.Dr. Omer has published widely in peer reviewed journals including the New England Journal of Medicine, JAMA, Lancet, British Medical Journal, Pediatrics, American Journal of Public Health, Science, and Nature and is the author of op-eds for publications such as the New York Times, Politico, and the Washington Post.