How COVID-19 vaccines work
Vaccines help our immune system fight infections in the future. COVID-19 vaccines will protect us from the virus that causes COVID-19 without having to get the illness.
It typically takes a few weeks after the last dose in a series to become fully protected. On the days after taking the vaccine, you may have a sore arm, aches, fatigue or fever, but these are not harmful. These symptoms signal that your immune system is developing protection from the virus.
Benefits of getting vaccinated
COVID-19 vaccines are meant to prevent you from getting COVID-19 and from spreading it to others. The ability of COVID-19 vaccines to protect us from spreading the virus to others is not yet known, but is being studied carefully.
When is a Community Sufficiently Vaccinated?
Vaccinations benefit both the person being vaccinated and the community at large. A community is sufficiently vaccinated when it reaches herd immunity. Herd immunity is a term used to describe when enough people have protection—either from previous infection or vaccination—that it is unlikely a virus or bacteria can spread within the community even if some people don’t have any protection themselves.
The percentage of people who need to have protection to achieve herd immunity varies by disease. Experts don’t yet know what percentage of people would need to get vaccinated to achieve herd immunity to COVID-19. However, the World Health Organization and Johns Hopkins Center have suggested at least a 70% vaccine coverage rate to reach population immunity through vaccination.
Why travel is risky
When you travel, you spend more time outside your home and come into contact with people outside your household. You are near new people in airports, train stations, gas stations, grocery stores, restaurants, hotels, short-term rentals, sightseeing attractions, and retail stores.
These new people may be exposing you to COVID-19, or you may be unknowingly exposing them. People arriving in California from other states or Californians returning from other states or countries could also introduce new sources of infection (potentially including new strains of the coronavirus) to California. This contributes to community spread of the disease, which leads to more illness and death.
Hospitals in our state are critically low in available ICU beds, so it’s important that we do all we can to take fewer risks and not spread COVID-19.
Postponing travel and staying home is the best way to protect yourself and others from COVID-19.