Why Is This Important
When the immune system first encounters a vaccine, it activates 2 important types of white blood cells.
First up are the plasma B cells, which primarily focus on making antibodies against the pathogen .
Unfortunately, this cell type is short-lived. Your body might be swimming in antibodies within just a few weeks. But without the second shot there is usually a rapid decline in antibodies against the pathogen.
Then there are the T cells, each of which identifies a particular pathogen to kill it.
Some of these memory T cells linger in the body for decades until they meet their target. This means immunity from vaccines or infections can sometimes last a lifetime. But you usually won’t have many of this cell type until there is a second exposure to that pathogen, which happens through the booster dose.
On second exposure to the same vaccine, the body can respond by creating a stronger immune response to fight the virus if required.
It is not yet known how long the COVID-19 vaccine protection will last. Clinical trials are currently happening to find out if we will need annual or longer booster doses to ensure long term immunity.
With new COVID-19 vaccine developments every day, its normal to have questions or concerns, and possibly feel hesitant about getting a vaccine. That’s why we’re providing accurate, evidence-based answers to questions about COVID-19 vaccines.
How Well The Vaccine Works
- Based on evidence from clinical trials in people ages 16 years and older, the Pfizer-BioNTech vaccine was 95% effective at preventing laboratory-confirmed infection with the virus that causes COVID-19 in people who received two doses and had no evidence of being previously infected.
- In clinical trials, the Pfizer-BioNTech vaccine had > 90% efficacy in preventing laboratory-confirmed COVID-19 infection in children ages 515 years, and the immune response in children ages 515 years was at least as strong as the immune response in people ages 1625 years.
- In clinical trials, the vaccine also had > 90% efficacy in preventing COVID-19 among people of diverse age, sex, race, and ethnicity categories and among people with underlying medical conditions.
- Evidence shows mRNA COVID-19 vaccines offer similar protection in real-world conditions as they have in clinical trial settingsreducing the risk of COVID-19, including severe illness, by 90% or more among people who are fully vaccinated.
- CDC will continue to provide updates as we learn more.
How Mrna Vaccines Work
To trigger an immune response, many vaccines put a weakened or inactivated germ into our bodies. Not mRNA vaccines. Instead, mRNA vaccines use mRNA created in a laboratory to teach our cells how to make a proteinor even just a piece of a proteinthat triggers an immune response inside our bodies. That immune response, which produces antibodies, is what protects us from getting infected if the real virus enters our bodies.
Recommended Reading: How Long Cvs Rapid Test
Why Do I Need To Get A Covid
A super appears on a pink background: COVID-19 vaccine questions
Cut to a new super on a white background with a pink border: Why do I need to get a COVID-19 booster dose? I already had 2 doses of a COVID-19 vaccine.
Cut to a doctor sitting at a desk, then a super appears:
- Dr. Shelly McNeil
The doctor answers the question.
Dr. Shelly McNeil: Vaccines have helped to protect us against COVID-19. Over time, antibody levels produced by the body in response to the primary vaccine series decrease. We can improve our protection against serious illness by getting a vaccine booster.
COVID vaccine boosters increase antibody levels and improve our bodys immune response, which gives us better protection against serious illness. Thats why its important to get your COVID vaccine booster as soon as you are eligible.
COVID-19 vaccine boosters are safe and effective. Theyve been reviewed and approved for use by Health Canada and will continue to be monitored for safety and effectiveness as long as theyre in use.
Getting a COVID-19 vaccine booster as soon as youre eligible, along with following other public health measures, is the best way to continue to protect yourself against serious illness and hospitalization due to COVID-19.
Contact your local public health office to find out when and where you can get your COVID-19 booster.
Cut to a white screen with a pink border: Got questions?
Cut to a new white screen with a pink border:
- University of Calgary
Experts Recommend All Eligible Take The Booster Dose As The Covid Virus Has Mutated Significantly Since Last Year
On April 10, India launched precautionary Covid vaccine doses for individuals in the 18 to 59 age group. In the first few hours that day, 9,500 doses were administered to eligible beneficiaries who had turned up to boost their immunity against Covid-19. It has been 11 months since I got my dose and I have been really worried about being susceptible to Covid again. I was glad to take the shot as I have elderly parents, said Alok Mehta, 45, a Delhi-based chartered accountant.
All those who took their second Covid shot nine months ago are eligible to take the third precautionary dose. Given that the virus has mutated significantly, experts recommend getting the immunity booster. Antibody levels fall after some time. Getting a booster will certainly help ensure a stronger immune response to Covid. Moreover, as Covid protocols are being scaled down in many states, the booster is a sensible option to ensure as little transmission of the virus as possible, says Dr Sushila Kataria, senior director of internal medicine at Medanta, Gurugram. Dr Kataria was one of the first to treat Covid patients in Haryana back in 2020. The disease has become milder but this doesnt mean its impact on health is negligible. Those eligible must get vaccinated for their sake and that of the community, she adds.
You May Like: Cvs Rapid Testing Price
Cdc Knew About Illicit Doses
It turns out the CDC knew the whole time that people were breaking the rules, according to a senior physician there.
We were aware of the phenomenon, the CDC doctor said. We actually monitor it for those states that share their vaccine registry with us, we could see that people were engaging in this practice.
And of course, CDC scientists read the Hopkins studies. In fact, the CDC doctor said the governments okay for extra doses relied to a great extent on the Hopkins data on people who broke the rules and got unauthorized shots something Segev, who led the Hopkins study calls a strange irony.
The CDC physician was asked what he told immune-compromised friends last year who wanted to know if they should get unauthorized doses.
As a federal official, I cannot officially endorse that, the doctor answered. But as a human being, I understand that. If its going to allow you to take care of something personal and youre ok with it ethically and there are no medical contraindications, I would endorse it.
The doctor asked not to be identified based on longstanding norms about government employees speaking to the media.
But he wonders why there werent separate clinical trials done early on with immune-compromised participants.
That wasnt done, and it put everyone in a bind, he said.
About Author: Lisa Coon
Lisa Coon is a Writing Coordinator for OSF HealthCare, where she has worked since August 2016. A Peoria native, she is a graduate of Bradley University with a degree in journalism. Previously, she worked as a reporter and editor at several newspapers in Iowa and Illinois.She lives in Groveland with her husband and son. In her free time she likes to cook, bake and read. She freely admits that reality TV is a weakness, and she lives by the quote, The beach is good for the soul.
You May Like: Cvs Antigen Test Cost
Can I Do Anything Ahead Of Time To Reduce Any Side Effects From The Vaccine
You should wait until after being vaccinated to see how you feel. If you do experience side effects, it is OK to take an over-the-counter drug to lower a fever, reduce chills, or relieve a headache or body aches. Its important that you do not take these drugs before getting your vaccine as there are theoretical concerns that some pain relieving drugs may interfere with the immune response to the vaccine. It is also unclear if taking medication ahead of time actually works to reduce post-vaccine symptoms.
Is It Still Possible To Get Covid
The COVID-19 vaccines are among the most effective vaccines in history. They are as effective if not more than vaccines for polio, chicken pox, measles and the flu.
The chances of getting sick after vaccination are minimal. Studies show even if you develop COVID-19 after being vaccinated, you are unlikely to get severely ill. Flu vaccines are less effective than the COVID vaccines, but they can protect you from more severe flu illness and hospitalization. The COVID-19 vaccines are even more powerful.
Learn more about the COVID-19 vaccines »
Don’t Miss: Cvs Nasal Swab Test
Ingredients That Are Not Used In Covid
The above table lists ALL ingredients in the Pfizer-BioNTech COVID-19 vaccine. There are NO ingredients in this vaccine beyond what is listed in the table. The Pfizer-BioNTech COVID-19 vaccine has:
- No preservatives like thimerosal or mercury or any other preservatives.
- No antibiotics like sulfonamide or any other antibiotics.
- No medicines or therapeutics like ivermectin or any other medications.
- No tissues like aborted fetal cells, gelatin, or any materials from any animal.
- No food proteins like eggs or egg products, gluten, peanuts, tree nuts, nut products, or any nut byproducts .
- No metals like iron, nickel, cobalt, titanium, rare earth alloys, or any manufactured products like microelectronics, electrodes, carbon nanotubes or other nanostructures, or nanowire semiconductors.
- No latex. The vial stoppers used to hold the vaccine also do not contain latex.
Why Mrna Vaccines Need Two Doses To Best Work And What Delays Might Mean
Editors Note: Dr. William Petri, a chaired professor of infectious diseases and international health at the University of Virginia and vice chair for research in the Department of Medicine, wrote this piece for The Conversation. His lab is studying the effects of COVID-19 on the immune system and seeking new treatments.
With the U.S. facing vaccination delays because of worker shortages and distribution problems, federal health officials now say its OK to push back the second dose of the two-part vaccine by as much as six weeks.
As an infectious disease doctor, Ive been fielding a lot of questions from my patients as well as my friends and family about whether the COVID-19 vaccine will still work if people are late receiving their second dose.
Why You Need Two Doses 3-4 Weeks Apart
Two doses, separated by three to four weeks, is the tried-and-true approach to generate an effective immune response through vaccination not just for COVID, but for hepatitis A and B and other diseases as well.
The first dose primes the immune system and introduces the body to the germ of interest. This allows the immune system to prepare its defense. The second dose, or booster, provides the opportunity for the immune system to ramp up the quality and quantity of the antibodies used to fight the virus.
In the case of the Pfizer and Moderna COVID-19 vaccines, the second dose increases the protection afforded by the vaccine from 60% to approximately 95%.
Recommended Reading: Cvs Pcr Test Cost
Who On Booster Doses
In September, The World Health Organisation had called for a moratorium on booster vaccination for healthy adults until the end of 2021 to counter the persisting and profound inequity in global vaccine access.
The WHO prioritises Global COVID-19 Vaccination by mid-2022 and has stated Vaccine effectiveness data for a booster dose are being published from an increasing number of countries, but remain limited in follow-up time. All studies demonstrate an improvement in protection against infection milder disease as well as severe disease and death.
Crossing State Lines To Get Unauthorized Vaccine Shots
Weitzen said he didnt have to lie to get his third dose last May. He made an appointment, showed up at a pharmacy near his home in New Jersey, rolled up his sleeve, and was given the injection.
Others, however, say it wasnt quite so straightforward.
Phil Canuto, a kidney transplant recipient who lives in Ohio, got his third shot on August 15, two days after the CDC recommended them for immune-compromised people.
A blood test a few weeks later showed he still had only minimal antibody levels against the virus. Over the next few months, as the Delta variant raged across the country, Canuto grew more fearful that he would contract Covid-19.
I felt basically unprotected, he said.
In October, the CDC updated its guidelines to say the immune-compromised could start getting fourth doses. But the agency recommended a six-month interval between third and fourth doses and only two months since Canutos third dose.
I was obviously worried and not quite sure what to do. Ohio has a pretty good database, so if Id gone in Ohio, they would have picked up that he was getting a fourth shot earlier than allowed under CDC guidelines.
So, two days after Thanksgiving, while visiting family in Pennsylvania, Canuto went to a pharmacy and said he was there to get his first shot.
After his first three shots, Canuto had felt fine. But the day after his fourth shot, he developed a fever, chills and a headache.
You May Like: Does Cvs Rapid Test Cost Money
Ndtv: Why Is Booster Dose Important At A Time When We Have Removed Mask Mandates From Several States
Dr Sarin: This is for your protection. Vaccines are for the protection of you and those around you. If you see around NCR and Haryana, we have observed a slight rise in the fresh cases in last week, and the positivity rate is 1.2 per cent which had come down to about 0.1 per cent, so keeping that in mind, I think it is wise to get the vaccine, precautionary dose and wear a mask for your own and your familys safety. People are not following any of the COVID protocols now, but I feel if we get another wave, it will be very difficult yet again. So the least we could do on our part is these two things for at least 6 months to a year more. People are hesitant about the third dose, but it is fairly proven from global data that the immunity gained from 2 doses, does come down after 9 months so there is no harm in boosting your antibodies with another jab. I am really happy with this policy decision.
Adverse Outcomes Exceedingly Rare
A Morbidity and Mortality Weekly Report study by National Institutes of Health and Centers for Disease Control and Prevention researchers involved 1,228,644 American adults who completed their primary COVID-19 vaccination regimen from December 2020 to October 2021. The period was marked by the emergence of the more transmissible Delta variant.
The researchers used data from 465 healthcare facilities in the Premier Healthcare Database Special COVID-19 Release to evaluate the frequency of and risk factors for severe COVID-19 after two doses of the mRNA COVID-19 vaccines from Pfizer/BioNTech or Moderna or one dose of the Johnson & Johnson vaccine 14 or more days before illness onset. Of all vaccinees, 72.8% received Pfizer, 20% were given Moderna, 6.5% received J& J, and 0.8% received an unspecified vaccine.
Severe COVID-19 was defined as hospitalization for acute respiratory failure, the need for noninvasive ventilation, intensive care unit admission , or death .
Adverse COVID-19 outcomes were rare, at 0.015%, and the death rate was 0.003%. Of the 128,664 people who completed primary COVID-19 vaccination during the study period, 2,246 were infected, and 189 experienced a poor outcome, including 36 deaths .
Among infected patients, 24 survived and were admitted to an ICU, and 129 survived and were diagnosed with acute respiratory failure or needed noninvasive ventilation but were not admitted to an ICU.
Don’t Miss: How Much Is Pcr Test At Cvs
What Are Indias Precautionary Doses
- As per Ministry of Health and Family Welfare ‘s guidelines, beneficiaries above 18 years who have received two doses, are eligible to receive another dose of COVID-19 vaccine.
- The prioritisation and sequencing of this precaution dose would be based on the completion of 9 months, or 39 weeks, from the date of administration of the second dose.
- Co-WIN system will send SMS to such beneficiaries for availing the precaution dose when the dose becomes due.
- The details of administration of the precaution dose will be suitably reflected in the vaccination certificates.
- Private vaccination centres can charge up to a maximum of Rs 150 as service charge for vaccination, over and above the cost of the vaccine.
- Precaution dose will be of same vaccine which has been used for administration of first and second dose.