Health Conditions A-Z Infectious Diseases COVID-19 How Long After COVID Can I Get a Booster? An updated booster dose of the Moderna or Pfizer vaccine helps protect you against emerging variants of the COVID-19 virus. By Lambeth Hochwald Lambeth Hochwald Lambeth Hochwald is a believer that everyone has a story to tell. As a New York City-based journalist, she has been busily covering COVID-19 and its effects on everyone from college students and their parents to restaurant workers and ER doctors. Over the last few decades, she's written for the New York Post, CNN, Parade, WebMD, Millie, Reside, the Food Network, Delish, and Architectural Digest, always with the same mandate to be compassionate, hence the hashtag #compassionatejournalism that she includes in her email auto-signature. When she's not juggling assignments, she's helping to teach the next generation of journalists in her role as an adjunct professor of journalism at NYU's Arthur L. Carter Journalism Institute. health's editorial guidelines Updated on December 18, 2023 Medically reviewed by Kashif J. Piracha, MD Medically reviewed by Kashif J. Piracha, MD Kashif J. Piracha, MD, FACP, FASN, FNKF, is a practicing physician at Methodist Willowbrook Hospital. learn more Trending Videos Close this video player d3sign / Getty Images You might wonder how long after COVID you can get a booster. The Centers for Disease Control (CDC) advises waiting for a booster dose of the Moderna or Pfizer vaccine until after your isolation period ends. Everyone aged 5 years and older should get one dose of the updated Pfizer-BioNTech or Moderna COVID-19 vaccine. Read on to learn about how getting a booster provides added protection against the SARS-CoV-2 virus and its variants, such as Omicron. Why Do You Need a Booster After COVID? The National Institutes of Health (NIH) advises getting a booster to help protect you against evolving strains of the SARS-CoV-2 virus, even if you previously had COVID-19. "I always like to remind people what the word 'booster' means," Michael Bauer, MD, a pediatrician at Lake Forest Pediatric Associates, told Health. "It reminds your immune system to rev up again [to produce more antibodies]." SARS-CoV-2 has evolved to produce many different variants since the COVID-19 pandemic began. For example, the Omicron variant became predominant in November 2021. There are several Omicron subvariants, and experts say the virus will continue to evolve. Staying up-to-date with your COVID-19 vaccines, including booster doses, helps protect you against new subvariants. For example, the bivalent booster targets Omicron subvariants in addition to the original SARS-CoV-2. The CDC notes that people who previously had COVID-19 and do not receive a booster are likelier to become reinfected than others. How Long Does It Take for the COVID-19 Booster To Be Effective? How Long Should You Wait After Having COVID? The CDC advises waiting to get a booster until after your isolation period ends. You risk spreading COVID-19 to healthcare providers and others if you seek a booster while sick. The CDC urges you to isolate for at least five days if you test positive for COVID-19, with day 0 being when your symptoms begin. You may end your isolation period after five days if you do not have a fever for at least 24 hours without using a fever reducer or have no symptoms. Avoid others who may get very sick from COVID-19 and wear a high-quality mask until day 11. The CDC advises isolating for at least 10 days if you have moderate symptoms. Consult a healthcare provider about when to end your isolation period if you have severe symptoms or a weak immune system. When Is the Best Time To Get a Booster? The CDC says people who previously had COVID-19 should receive a booster within three months after infection for the best protection. Of note: As of 2023, you do not need to wait 90 days to receive a vaccine or booster if you had monoclonal antibody treatment. People are unlikely to get reinfected right away. A study published in 2021 noted that the risk of getting another COVID-19 infection within 90 days is exceedingly low. That's because people develop antibodies to help fight off the virus, said Dr. Bauer. "If you've been vaccinated and then get a COVID infection, that infection is actually serving a similar role to a booster," said Dr. Bauer. "In effect, you are getting a booster at that point by natural immunity." Consider getting a booster as soon as possible after a COVID-19 infection if you: Have a risk of severe illness from COVID-19Have a close contact or loved one with a high risk of severe illness from COVID-19Live in an area with a high COVID-19 hospital admission level What Are the Benefits of the Booster? In general, the CDC urges you to stay up-to-date on your COVID-19 vaccines, which reduce the risk of severe illness from COVID-19, hospitalization, and death. The NIH reports that staying up-to-date with your COVID-19 vaccines, including booster doses, helps protect you against emerging variants. Boosters are a "more reliable means of offering longer-term protection" than natural immunity, Jonathan Li, MD, an infectious disease specialist at Brigham and Women's Hospital, told Health. "We just don't know how well that recent infection is going to protect that individual against subsequent infection, whereas a booster is standardized," said Dr. Li. A study published in 2022 found that previous infection protected people 46.1% against the Omicron subvariant BA.2. That protection increased to 77.3% among people who had previous infection and three doses of the Pfizer-BioNTech vaccine. Who Should Get a Booster? Everyone older than 6 months may receive COVID-19 vaccines, including a booster dose. What kind and when you may receive a booster depends on your initial vaccination series and how long it's been since your last dose. Your age and health status may also play a role, as well. According to the CDC, here's how many booster doses you need to stay up-to-date: Children aged 6 months to 4 years: May need multiple booster doses, depending on how many and what kind (e.g., Moderna or Pfizer) they have received People aged 5 and older: One dose of the updated Pfizer-BioNTech or Moderna COVID-19 vaccine People with a weak immune system: Eligible for additional doses of updated COVID-19 vaccines Pregnancy and COVID-19 Booster Shots: What You Should Know A Quick Review The SARS-CoV-2 virus continues to evolve and produce new variants that may cause reinfection. It's essential to keep up-to-date with your COVID-19 vaccines and boosters, even if you previously tested positive. Vaccination helps protect you against severe illness, hospitalization, and death. According to the CDC, people who previously had COVID-19 and do not receive a vaccine or booster within 90 days after infection are more likely to get COVID-19 again than others. Consult a healthcare provider about receiving a booster dose if it's been three months since you've had COVID-19. FAQs Frequently Asked Questions 1. Am I still contagious after seven days of COVID? You are most likely contagious during the first five days after your symptoms begin with mild illness or 10 days with moderate or severe illness. Some evidence suggests the rapid antigen tests do not detect the SARS-CoV-2 virus after nine days. The CDC advises avoiding people who may get very sick from COVID-19 and wearing a high-quality mask until day 11. 2. Can I get a booster and flu shot at same time? The CDC says it's safe to get COVID-19 and flu vaccines at the same time. One vaccine will not affect how your body develops protection from the other. The possible side effects of vaccination, including headache and muscle pain, are the same whether you get both vaccines at the same time or not. Updated by Karen Pallarito Karen Pallarito Karen is a senior editor at Health, where she produces health condition “explainers” backed by current science. learn more Was this page helpful? Thanks for your feedback! Tell us why! Other Submit 12 Sources Health.com uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Centers for Disease Control and Prevention. Frequently asked questions about COVID-19 vaccination. National Institutes of Health. COVID-19 vaccines. National Institutes of Health. Booster vaccine targeting Omicron offers broader COVID-19 protection. Centers for Disease Control and Prevention. Variants of the virus. Centers for Disease Control and Prevention. Stay up to date with COVID-19 vaccines including boosters. Centers for Disease Control and Prevention. Isolation and precautions for people with COVID-19. Centers for Disease Control and Prevention. Getting your COVID-19 vaccine. Harvey RA, Rassen JA, Kabelac CA, et al. Association of SARS-CoV-2 seropositive antibody test with risk of future infection. JAMA Intern Med. 2021;181(5):672-679. doi:10.1001/jamainternmed.2021.0366 Altarawneh HN, Chemaitelly H, Ayoub HH, et al. Effects of previous infection and vaccination on symptomatic Omicron infections. N Engl J Med. 2022;387(1):21-34. doi:10.1056/NEJMoa2203965 Centers for Disease Control and Prevention. Frequently asked questions about COVID-19 vaccination. Cevik M, Tate M, Lloyd O, et al. SARS-CoV-2, SARS-CoV, and MERS-CoV viral load dynamics, duration of viral shedding, and infectiousness: A systematic review and meta-analysis. Lancet Microbe. 2021;2(1):e13-e22. doi:10.1016/S2666-5247(20)30172-5 Centers for Disease Control and Prevention. Possible side effects after getting a COVID-19 vaccine.