Over 4 billion doses of COVID-19 vaccines have been administered globally, but the virus continues to spread even in countries with very high rates of vaccination such as Israel.

Sufficiently widespread vaccination (and natural antibodies from infection) could eventually succeed in eradicating the virus; alternatively it might become an endemic virus like other coronaviruses. Future mutations might require the development of new types of booster doses. Animal reservoirs complicate the picture even more, as full vaccination in humans might not be sufficient to drive it to extinction.