Vaccine FAQs, Answered By Mayo Clinic

A volunteer receives an injection in  a COVID-19 vaccine trial developed at the University of Oxford in Britain in conjunction with the pharmaceutical company AstraZeneca. (Siphiwe Sibeko/Pool via AP)

Are vaccines safe, effective, and necessary? Answers to common questions from Mayo Clinic doctors | 

Nov 30, 2020

Concerns from those who are hesitant about vaccines often fall into these categories:

  • Can I trust the source of the recommendation?
  • Is the vaccine effective?
  • Is the vaccine safe?
  • Is the vaccine needed?
  • Are there reasonable alternatives?

November 30, 2020

...article continued below
- Advertisement -

Mayo Clinic – Hesitance toward vaccines is common, says Dr. Robert M. Jacobson, medical director of Primary Care Immunization Program at Mayo Clinic.

He says health care providers should expect questions about the COVID-19 vaccine when it becomes available.

Mayo Clinic relies on the Advisory Committee on Immunization Practices (ACIP), an independent authority that meets three times a year to decide which vaccines are recommended. The committee is a trusted source, Dr. Jacobson says.

It is independent of Congress, the Food and Drug Administration and the National Institutes of Health, and it uses an evidence-based system that addresses questions of effectiveness and safety, as well as need and reasonable alternatives.

The committee also works with organizations such as the American Academy of Pediatrics, American Academy of Family Physicians, the American College of Physicians, and the American College of Obstetricians and Gynecologists to ensure there is broad agreement with its recommendations.

...article continued below
- Advertisement -

“We will be looking at the scientific evidence. We will be able to address the issues of effectiveness, safety, need, and reasonable alternatives, to provide trusted information for our patients and staff.” – Robert Jacobson, M.D.

Effectiveness is determined by using randomized, controlled trials to discern which outcomes are coincidences and which are caused by the vaccine.

The trials require tens of thousands of volunteers who are randomized into two groups, one that receives a placebo and one that receives the vaccine. Both groups of volunteers are studied to see whether they develop the infection.

The researchers don’t know which group volunteers are in because identities are masked until the outcomes are collected.

Safety also is tested by the randomized, controlled trials. The trials track bad outcomes, such as reactivity (fever or injection-site soreness), illnesses, hospitalizations and deaths.

Recommended vaccines must meet a higher safety standard than prescription medicines, Dr. Jacobson says, because they are preventive and given to otherwise healthy people. And the safety results are more precise. Many more people (from 10 to 100 times as many) are tested in these trials.

The necessity of the vaccine is measured by epidemiology studies that examine large population groups to determine risk of the disease.

There are some vaccines the Food and Drug Administration licenses as effective and safe, but they are not needed. The risk for the disease prevented by these vaccines is too low to justify their use.

Alternatives are considered, as well. Again, the Advisory Committee on Immunization Practices does not recommend some vaccines found to be effective and safe by the FDA.

In these cases, it is because an alternative to the vaccine is a better choice.

The committee recommends only vaccines that meet all four requirements — effectiveness, safety, need and lack of reasonable alternatives.

And Mayo Clinic recommends for its patients what the Advisory Committee on Immunization Practices recommends

Information in this post was accurate at the time of its posting. Due to the fluid nature of the COVID-19 pandemic, scientific understanding, along with guidelines and recommendations, may have changed since the original publication date.

For more information and all your COVID-19 coverage, go to the Mayo Clinic News Network and mayoclinic.org.

This article is written by Mayo Clinic Staff. Find more health and medical information on mayoclinic.org.


AstraZeneca Botches Covid Vaccine Trial

Fauci: Get Ready For Your Vaccine

Pediatricians Fear Risks To Kids From Rising Vaccine Hesitancy

ALSO ON HEADLINE HEALTH TODAY: Cop Who Lit GF’s Crotch Still Jailed | China’s Deadly Cover-Up Of COVID-19 | When Alzheimer’s Patients Get Lost

- Advertisement -


Pa. Voters to Decide Whether Governor Can Keep Nanny-State Powers

Republican lawmakers across the country have tried to roll back the emergency powers that governors wielded during the COVID-19 pandemic, as they ordered businesses shut, mask-wearing in public and students home for distance learning. Pennsylvania‘s Legislature is now taking its case to the ballot.

Hopes for Herd Immunity Fade As Virus Nears Endemic Status

If the virus continues to run rampant through much of the world, it is well on its way to becoming endemic, an ever-present threat.

Risk Of Dying From Covid-19 40 Times The Risk Of Vaccine Blood Clot

CNN – The risk of dying from Covid-19 is 40 times the risk of developing a rare blood clotting condition after getting the Johnson & Johnson vaccine.

The Real Reason ‘Ellen’ Got Canceled

"The toxic company culture, coupled with increased production protocols and costs, created the perfect storm for this completely disjointed show."

GOP Sens. Turn Up Heat On Fauci, CDC

ABC NEWS – Centers for Disease Control and Prevention Director Dr. Rochelle Walensky was forced to defend her agency's guidance and even its integrity...

Schools Ditch “Communist” Mask Rules

As a lengthy, bitter fight over mask requirements for students neared its conclusion, the chairperson of a Florida school board announced that she would agree to lift a mandate that had been in place since September even though she preferred leaving it in place until the end of the academic year. Parents hurled insults in response ...

Scientist Keeps Repeating Known COVID Falsehoods

An American scientist claims that Covid-19 vaccines pose safety concerns, including sterilization and changes to DNA, in remarks shared on social media. But experts and public health bodies say there is no evidence that mRNA shots are causing reproductive problems, and are not modifying the genes of recipients.

Black Men Dying At Alarming Rate From Drug Overdoses

Overdose deaths in Massachusetts are rising again, with the most drastic increase in deaths occurring among Black non-Hispanic men in the state.

Florida Teacher Gets 15 Years In Hidden-Cam Case

TAMPA, Fla. – A 52-year-old teacher was sentenced to 15 years in prison for secretly recording videos of students as they changed clothes in...

Is Vaccine Disrupting Women’s Periods?

From heavy flow to even bleeding during menopause - women say they're experiencing different cycles after getting vaccinated.
- Advertisement -