Simmie earned a bachelor's degree in general biology (pre-medicine) from the University of Liberia, and a recent graduate of the Xiangya School of Public Health, Central South University, China with a master's degree (Hons) in public health and health management. Simmie aspires to ultimately create a global health nonprofit to help build stronger, sustainable, equitable, and high-quality health systems for the world's poorest regions, thereby protecting impoverished, marginalized, and underserved people from sickness and death.

Prior to graduate school, Simmie worked for InsightSTEM, the Government of Liberia, and local nonprofit organizations on a variety of programs that promote health and education. In various roles, he was able to collaborate with doctors, health professionals, and patients in developing programs that made significant contributions to the health of citizens through active health management and delivery of health care services. The experiences stimulate an interest to learn more and do more for the health of the poor and vulnerable populations.

As a graduate student, Simmie has assisted with planning, strategic, and technical support of various projects and programs around health systems management, health planning, and efforts to increase patients' access to vaccines and HIV and tuberculosis (TB) testing in low- and middle-income regions of China and Africa. Being a graduate research assistant, he managed diagnostic development and lab capacity building projects for the epidemic- and pandemic-prone diseases at the Health Management Center, Central South University. Simmie has worked as a principal investigator on a retrospective cohort study to examine the quality of life and psychological impact of the Ebola virus disease survivors in Liberia and had proposed for grant funding to provide psychosocial support for these survivors.

Simmie joined the Hunan Tuberculosis Control Institute/ Hunan Chest Hospital to help accelerate the investigation on latent infection of Mycobacterium tuberculosis in the general population of Hunan, supporting laboratory capacity and health systems strengthening. Here, he was awarded the Distinguished International Scholar Award.

His passion lies in promoting access to health care for the most vulnerable populations on a large scale. His primary focus addresses the health of people living in developing countries. In these populations, health concerns include not only infectious and tropical diseases (such as HIV/AIDS, TB, sexually transmitted diseases, and malaria) but also chronic and non-infectious diseases. The approaches to these problems, however, need to be innovative in solving unique challenges for populations, hence the importance of navigating the implementation of new health care delivery systems, technological innovations, research and budget reform, and growing emphasis on preventive care.