Both of the vaccines currently approved for use in the U.S., Moderna and Pfizer, now require two doses — but what happens if you are unable to receive the second dose as scheduled? When patients are unable to adhere to their prescribed vaccination schedule, this is a medication adherence issue. As with many medication adherence problems, this can have dangerous health consequences: giving the virus time and space to mutate. Additionally, Dr. Bob Bollinger, infectious disease expert and emocha’s Medical Director states, “People who receive only one shot or a delayed second shot may not be as well-protected from COVID-19. It is also possible that receiving only one shot or delaying the second could mean a shorter duration of protection.” Moreover, there is insufficient research regarding COVID-19 vaccine efficacy when patients only receive the initial dose. Doctors recommend getting both doses as scheduled, in addition to other public health strategies such as masking and sanitization until we reach herd immunity.