Vaccines take time to work. After getting a COVID-19 vaccine, it takes a while for the immune system to fully respond and provide protection from the virus. For the Moderna and Pfizer COVID-19 vaccines, it takes up to two weeks after the second shot to become appropriately protected.
Nearly 40 million people around the world are living with HIV, and experts believe about 20% do not know their status. In the U.S., more than 1 million people in the U.S. are living with HIV.