Often times, viruses and bacteria change over time through a process called mutation, which produces new variants. Old vaccines do not always work against new variants. Additionally, no vaccine provides 100% protection. Vaccines can also lose their effectiveness over time. This decline in effectiveness is normal and does not mean the COVID-19 vaccines don’t work. Getting updated vaccine shots as they become available helps maintain the protection offered by vaccines by reminding the body how to fight off COVID-19 infection. They also teach the body what newly evolved variants of the COVID-19 vaccine look like. Updated vaccines used to be called booster shots, but that phrase is slowly being replaced with the name updated vaccines.

A new type of vaccine is currently being tested to prevent COVID-19 that involves a nasal spray, as opposed to a shot. Preliminary studies have shown promise for this type of vaccine. Research suggests this method is safe, effective, may be more tolerable and have fewer side effects than the traditional shot. However, more research is needed before this option becomes available to the public.