UC Davis Health is vaccinating ages 5 and older

We're offering COVID-19 vaccines (first, second, and third doses) to anyone age 5 and older. Please use MyUCDavisHealth or California’s MyTurn.ca.gov to schedule your vaccine appointment.

UC Davis Health patients and non-patients can schedule appointments at our clinics in Auburn, Carmichael, Davis, Elk Grove, Folsom, Rancho Cordova, Rocklin, Roseville, and Sacramento.

The Omicron variant of COVID-19 is spreading more rapidly than other strains of the virus. This is causing an increase in cases and a high demand for testing. If you have been exposed to someone with COVID-19 or have COVID-19 symptoms and are waiting for a test or your results, stay home and isolate from others. Learn more about when you should get tested

You can also reach out to our experts using UC Davis Health’s convenient Telehealth Express Care for urgent needs or extended-hours video visits. Express care services are open Monday – Friday, 8 a.m. to 8 p.m. and Saturday – Sunday 9 a.m. to 6 p.m.

Read more: UC Davis Health infectious disease experts answer questions more about Omicron

What is the Omicron variant of COVID-19, and how is it different than other strains?

The Omicron variant has more mutations than any other variant that researchers have discovered. Many of the mutations are in the spike protein, which is what attaches to the cells and relates to how the virus is spread. For this reason, all vaccines being used are focused on targeting and developing an immune response to the spike proteins.

Are the COVID-19 vaccines effective in protecting against Omicron?

Since the Omicron variant is so new, health experts do not have a clear idea how effective the vaccines will be. There is a potential that COVID-19 vaccines might not be as effective with new variants. However, the more antibodies a person has, the more protected they will be. That’s why everyone is encouraged to get a COVID-19 booster shot once you're eligible. Preliminary evidence suggests that vaccines are less effective against Omicron compared with Delta. But vaccines still protect well against serious illness such as hospitalization.

Does the Omicron variant cause more severe illness than other strains of COVID-19?

Health experts have very little data about the illness that comes with Omicron. Initial reports suggest that it may cause milder illness compared to previous variants. However, these infections may be mostly in young and healthy people who are less likely to get severely sick. Researchers are hoping to learn more soon about Omicron and whether it can cause severe illness

Is the Omicron variant able to spread more easily than other COVID-19 strains?

According to the U.S. Centers for Disease Control and Prevention (CDC), Omicron likely spreads more easily than the original COVID-19 virus. It appears to be much more contagious compared to the Delta variant, as it's quickly become the dominant strain in the U.S. The CDC said it expects that people can spread Omicron even if they’re vaccinated or don’t have symptoms.

Learn more about the Delta variant and symptoms related to it

Should you do anything different for the Omicron variant?

You should continue to practice good health hygiene, get your COVID-19 vaccine, and continue to mask when you're around others outside your household.

What does the Omicron variant tell us about future COVID-19 strains?

The more people who are infected, the more likely we are to see new variants. The message from health experts remains that everyone should be vaccinated against COVID-19. Every time COVID-19 infects someone, there’s a chance for more mutations, which can allow the virus to keep spreading. Stay vigilant and get vaccinated if you haven’t already.

The Omicron variant has more mutations than any other variant that researchers have discovered. Many of the mutations are in the spike protein, which is what attaches to the cells and relates to how the virus is spread. For this reason, all vaccines being used are focused on targeting and developing an immune response to the spike proteins.

All of the variants, including Delta and Omicron, cause similar COVID-19 symptoms, including cough, fever and fatigue. There is some evidence that fewer people with Omicron lose their taste and smell. Omicron is also less likely to cause severe disease such as pneumonia that may require treatment in the hospital.

In fully vaccinated and/or boosted people, Omicron symptoms tend to be mild. In unvaccinated people, symptoms may be quite severe, possibly leading to hospitalization or even death.

See which COVID-19 symptoms you should watch for

Learn more about the Delta variant and symptoms related to it

According to the U.S. Centers for Disease Control and Prevention (CDC), Omicron likely spreads more easily than the original COVID-19 virus. It appears to be much more contagious compared to the Delta variant, as it’s quickly become the dominant strain in the U.S. The CDC said it expects that people can spread Omicron even if they’re vaccinated or don’t have symptoms.

Omicron is more likely to cause less severe illness compared to other variants. For example, preliminary data suggest that infection with Omicron results in hospitalization at about half the rate compared to infection with Delta. Given how infectious Omicron is, it’s important for everyone to take all precautions, including getting vaccinated and wearing a mask.

Since the Omicron variant is so new, health experts do not have a clear idea how effective the vaccines are in preventing illness. There's a potential that COVID-19 vaccines might not be as effective with new variants. However, the more antibodies a person has, the more protected they will be. That’s why everyone is encouraged to get a COVID-19 booster shot once you're eligible.

Preliminary evidence suggests that vaccines are less effective against Omicron compared with Delta. But vaccines still protect well against serious illness such as hospitalization.

Omicron is incredibly infectious. Everyone should be masking (covering both the mouth and nose) when indoors around anyone not in their household and outdoors when in crowded settings. Several studies, including one from UC Davis, indicate how effective masks can be in protecting yourself and others. It’s important to remember that you may be asymptomatic and not know you are infected but still able to spread COVID-19. Wearing a mask in these situations helps protect vulnerable people you could unknowingly infect.

It’s difficult to estimate the protection from cloth masks since they aren’t standardized. Some studies suggest cloth masks are about 50% effective, compared to 60-70% for surgical masks and 95% for N95s. There is strong evidence that properly worn N95 masks are the most protective in terms of blocking transmission.

Cloth masks alone are not very effective against the most transmissible variants like Delta and Omicron. If an N95 mask is not available, a surgical mask covered with a cloth mask can be very effective.

Yes. It’s important to know if you're infected with COVID-19 for three reasons:

  1. If your illness gets worse, you’ll want to know so you can take advantage of COVID-19 treatments.
  2. You need to know whether to isolate so you can reduce your chances of infecting others, especially those who are more vulnerable to severe COVID-19.
  3. You will want to notify anyone you were recently in contact with so they can monitor their symptoms and get tested if needed.

Most likely. Unfortunately, Omicron is so easily spread that even those who are fully vaccinated and boosted may get the illness. If you know you had contact with an infected person, particularly in a higher-risk situation (such as an indoor space for a longer period with others who weren’t masked), testing is advised. You should also quarantine, watch for COVID-19 symptoms, stay away from others in your home, and wear a mask. If you test positive, then you should isolate.

However, if you were in a situation where people were outside, masked and distanced, the risk of infection is much lower. Instead of testing right away, you could monitor for COVID-19 symptoms and get tested if any develop.

Learn more about the difference between quarantine and isolation

Although it can vary, people are generally contagious between 1-3 days before Omicron symptoms show.

The more people who are infected, the more likely we are to see new variants. The message from health experts remains that everyone should be vaccinated against COVID-19. Every time COVID-19 infects someone, there’s a chance for more mutations, which can allow the virus to keep spreading. Stay vigilant and get vaccinated if you haven’t already.

Learn how to schedule your COVID-19 vaccine at UC Davis Health