Advertiser Disclosure

Advertiser Disclosure: The credit card and banking offers that appear on this site are from credit card companies and banks from which receives compensation. This compensation may impact how and where products appear on this site, including, for example, the order in which they appear on category pages. does not include all banks, credit card companies or all available credit card offers, although best efforts are made to include a comprehensive list of offers regardless of compensation. Advertiser partners include American Express, Chase, U.S. Bank, and Barclaycard, among others.

  • Date


Dig Deeper


Become a Money Crasher!
Join our community.

Should I Get a Flu Shot? – Vaccine Effectiveness, Side Effects & Types

According to the Centers for Disease Control (CDC), during the 2019 – 2020 flu season, 39 to 56 million people in the United States fell ill. Of these people, 410,000 to 740,000 were hospitalized and 24,000 to 62,000 died.

This year, with the COVID-19 pandemic still sweeping the globe and increased fears about a second wave this fall and winter, Mark Thompson, an epidemiologist in the Influenza Division at the Centers for Disease Control and Prevention, tells NPR it’s even more critical to get a flu shot. In an interview with The Hill, William Schaffner, medical director for the National Foundation for Infectious Diseases, says that getting a flu shot can significantly help mitigate the impact of COVID-19 infections on the health care system.

If more people get the flu vaccine this year, fewer people will need hospital care. In turn, there will be more doctors, nurses, and hospital beds to treat COVID-19 patients, which currently has no vaccine and, according to Johns Hopkins Medicine, likely has a higher mortality rate.

Another complication is that, according to the CDC, the flu and COVID-19, the disease caused by the new novel coronavirus, share many of the same symptoms, including fever and chills, body aches, cough, fever, and headache. Steven Pergam is a medical doctor and associate professor in the vaccine and infectious disease division at the Fred Hutchinson Cancer Research Center in Seattle. In the NPR interview, he says that as influenza begins making its way through the country, people with flu-like symptoms might head to emergency rooms for treatment or testing. It stands to reason all these additional patients might further strain the health care system and frontline workers.

There are plenty of ways to fight the flu naturally, and our current habits of frequent hand-washing, social distancing, and wearing masks will hopefully help limit the spread of influenza. However, a flu shot is the best way to give your family an added layer of protection against the influenza virus.

Brief History of the Flu Shot

Every year, the influenza virus makes its way around the world with varying levels of severity.

What may have been the first recorded influenza pandemic occurred in 1510, when the virus ravaged Africa and Europe. By far, the worst influenza pandemic was the Spanish flu outbreak in 1918, which lasted through 1920. Worldwide, 500 million people got sick, and up to 50 million people died from that strain alone. There was no vaccine.

The modern version of the flu vaccine was developed in the 1940s by University of Michigan medical researchers Thomas Francis Jr. and Jonas Salk, who discovered that manufacturers could mass-produce the vaccine using fertilized chicken eggs, a process still used today.

Challenges With Today’s Influenza Vaccine

Thanks to doctors’ and scientists’ continued research, we now have a widely available flu vaccine that saves countless lives every year. However, creating a new vaccine each season is incredibly complicated. And it’s certainly not foolproof.

According to the CDC, there are more than 100 national influenza centers in over 100 countries conducting constant surveillance of the virus. These centers collect virus samples from patients and send them to five World Health Organization (WHO) Collaborating Centers for Reference and Research on Influenza.

After extensive analysis of this data, twice each year, doctors and scientists with the WHO predict which strains will be most prevalent. They then make recommendations on which viral strains to include in the upcoming flu vaccine based on which ones are widely circulating and which strains might manifest later in the year. It takes six months to produce large quantities of the flu vaccine, so private-sector manufacturers get to work immediately growing these specific strains.

One challenge is that some viral strains don’t begin circulating until later into the season, which means they don’t surface in time to make it into that year’s vaccine. Another challenge is that some influenza strains, such as H3N2, don’t grow well in chicken eggs. That makes it difficult to include them in the vaccine in years when they’re widely circulating.

Strains can also mutate after vaccine production is underway, making the flu shot less effective.

How the Flu Vaccine Works

According to the CDC, manufacturers prepare the vaccine by infecting a fertilized hen’s egg with four viral strains. The Children’s Hospital of Philadelphia states that in most (but not all) vaccines, manufacturers add low levels of formaldehyde to inactivate the virus.

The United States Food and Drug Administration (FDA) considers the level of formaldehyde in the influenza vaccine to be very safe for both young children and adults. According to the CDC, the trace amounts of formaldehyde in the vaccine are lower than what’s naturally produced in the human body.

According to the National Institutes of Health, when the inactivated virus enters your system, your body produces antibodies within two weeks. Antibodies are proteins produced by the immune system. Their function is to recognize foreign pathogens, like the influenza virus, and destroy them. Once the virus is destroyed, antibodies will continue to circulate in the blood, ready to destroy any new invasions of that specific virus.

The Immunization Action Coalition states that antibodies produced from the flu vaccine only last around six months.

The problem is that the influenza virus can mutate and adapt rapidly. If you’re exposed, there’s always the chance the virus will mutate enough that your body’s antibodies are no longer effective against it.

According to University of Chicago Medicine, the antibodies produced when you get the flu vaccine latch on to distinct parts of the virus and destroy it. However, when the virus mutates, the site the antibodies are trained to latch on to might no longer be crucial to destroying the virus. That’s why some people still get the flu even after they’ve had a flu shot. And it’s why researchers have to develop a new vaccine every year.

Flu Vaccine Myths

There is a considerable amount of misinformation about the flu shot and vaccines in general. Learning the truth about the risks and benefits can help you make an informed decision.

1. False: A Flu Shot Can Give You the Flu

According to a 2015 study published in the journal Vaccine, 43% of Americans believe the flu shot can give you the flu.

The CDC unequivocally states that getting a flu shot will not make you sick with the flu. The flu shot contains the dead influenza virus, making it impossible for the vaccine to make you ill. The Immunization Action Coalition reports that less than 1% of people who receive the injectable flu vaccine come down with flu-like symptoms like fever and muscle aches. These symptoms are not the same as having the flu.

According to University of California San Francisco Health, these flu-like symptoms are often the result of an unrelated upper-respiratory illness present when you were vaccinated. You can also experience symptoms if you were already infected with the flu virus when you got vaccinated.

However, the CDC states that if you receive a weakened live virus inoculation like the nasal spray there’s a chance you could experience side effects such as runny nose, headache, cough, and sore throat. These flu-like symptoms can make some people think the nasal spray vaccine caused the flu.

2. False: Vaccines Cause Autism

Some parents are concerned that vaccines can cause autism in children. A 2017 article published in Dialogues in Clinical Neuroscience analyzed the research and history surrounding this myth, which began in the late 1990s, when Andrew Wakefield, a U.K. physician, published a study in The Lancet linking autism to the measles, mumps, and rubella vaccine. However, later investigation found that Wakefield’s original study was severely flawed due to scientific misconduct, conflict of interests, and outright falsehoods. The Lancet retracted the study, and the British Medical Association disciplined Wakefield. However, the myth that vaccinations cause autism has persisted and even spread since that time, despite dozens of studies disproving Wakefield’s claims.

The CDC maintains that there is no link between the flu vaccine and autism. And a 2013 study published in the Journal of Pediatrics found that vaccinations presented no increased risk in participating children.

3. Mostly False: Flu Shots Expose You to Mercury

Much of the controversy surrounding the flu shot has to do with the chemical used to preserve the vaccine, thimerosal. According to the CDC, thimerosal is a mercury-containing compound that helps prevent the growth of dangerous bacteria and fungus.

In the past, doctors drew multiple doses of the vaccine from a single vial. Thimerosal helped prevent contamination each time a doctor inserted a needle to draw out the vaccine.

However, in 1999, thimerosal was removed from almost all flu vaccines, and most vaccines transitioned to single-use vials. Today, no recommended single-use childhood vaccines contain thimerosal, and no recommended single-use children’s flu vaccine contains thimerosal (or the amount is close to zero). However, some flu vaccines in multidose vials might contain the chemical. According to the FDA, there are also thimerosal-free flu vaccines for adults and adolescents. If you’re concerned about mercury, consult your physician before vaccination.

Little Toddler Girl Getting Flu Shot

Types of Flu Vaccines

According to the CDC, flu season runs from October through March, but December and February have the highest number of infections, and infections can last as late as May. The CDC recommends you get a flu shot as soon as it’s available in your area.

There are two primary ways to administer the flu vaccine: a shot and a nasal spray.

Flu Shot

The flu shot is given with a syringe, usually in the arm, using the inactivated virus. The CDC recommends people aged 6 months or older, pregnant women, and seniors get a flu shot, while the nasal spray vaccine is approved for nonpregnant individuals aged 2 through 49.

Some groups have a higher chance of experiencing flu-related complications, and it’s especially important these people get vaccinated. Higher-risk groups include:

  • Pregnant women
  • Older adults
  • Children
  • People with chronic medical conditions, including diabetes, HIV or AIDS, asthma, cancer, chronic obstructive pulmonary disease, cystic fibrosis, kidney or liver disease, or obesity

People who should not get a flu shot include:

  • Children younger than 6 months of age
  • People with severe, life-threatening allergies to the flu vaccine or any of its ingredients, which might include any of its components, including gelatin and antibiotics

People aged 65 and older and those with weakened immune systems can get a high-dose flu shot, which might offer more protection against the flu.

Most people with a mild egg allergy can get a flu shot. However, those with a severe allergy should speak with their doctor and only get vaccinated in a setting where a doctor is present to monitor and treat severe allergic reactions. The CDC notes that there are two egg-free versions of the flu vaccine: Flublok Quadrivalent and Flucelvax Quadrivalent.

Nasal Spray

The nasal spray vaccine, also called the live attenuated influenza vaccine, is approved by the CDC for nonpregnant people and those aged 2 to 49 years. The nasal spray contains a live, weakened form of the virus.

Certain groups should not get the nasal spray vaccine. These groups include:

  • Children younger than 2
  • Children aged 2 to 4 who have asthma or a history of wheezing within the past 12 months
  • Children aged 2 to 17 who are receiving aspirin or salicylate-containing medications
  • Adults aged 50 and older
  • Pregnant people
  • People with a history of severe allergic reaction to the vaccine
  • Those with a weakened immune system
  • Those who have taken influenza antiviral drugs within the past 48 hours
  • People who care for those with severely weakened immune systems

The following groups should carefully consider using the nasal vaccine due to health concerns:

  • Children over age 5 with asthma
  • Those with underlying health conditions such as heart disease, lung disease, kidney disease, kidney or liver disorders, neurological or neuromuscular disorders, or metabolic disorders
  • Those who developed Guillain-Barre syndrome within six weeks of a previous flu vaccine

Some people believe getting the flu is no worse than getting the common cold. It’s critical you realize that complications from this disease can happen to anyone at any age, whether they’re healthy or have severe underlying health conditions. That’s especially true with children. The nonprofit organization Families Fighting Flu tries to put a face to the statistics with a page of heart-rending stories told by parents and family members who lost their previously healthy children to the influenza virus.

Pros of the Flu Vaccine

There are many benefits to getting a flu vaccine, some medical and others financial.

1. You Might Not Get Sick With the Flu

During the 2017 – 2018 flu season, the CDC estimates the flu vaccine prevented an estimated 6.2 million influenza illnesses, 3.2 million influenza medical visits, 91,000 hospitalizations, and 5,700 deaths.

When you get a flu vaccine, there’s no guarantee you won’t get the flu. However, you have a much higher chance of avoiding illness. The CDC estimates the vaccine reduces your likelihood of illness by 40% to 60%.

2. Symptoms Will Be Less Severe

Even if you get the flu, the vaccine can prevent some of the more severe symptoms.

A 2017 meta-analysis published in the Journal of Infections found that the influenza vaccine prevents related hospitalizations by 41%.

The vaccine can also help reduce the chance you’ll need ICU-level care if you do fall ill and need to be hospitalized.  A 2018 CDC study found that the flu vaccine reduced the risk of ICU hospitalizations by 82%. Vaccinated patients hospitalized with influenza symptoms also spent four fewer days in the hospital than those who did not get the vaccine. A 2018 study published in the journal Vaccine found that vaccinated adults who had to be hospitalized with the flu were 59% less likely to be transferred to the ICU.

The reduced severity of symptoms is also prevalent in children. A 2014 study published in the Journal of Infectious Diseases found that fully vaccinated children were 74% less likely to be admitted to the pediatric intensive care unit with severe symptoms.

3. You Can Save Money

The flu vaccine is very affordable compared to the cost of most other vaccines. Prices vary nationally and fluctuate slightly each year. You’ll pay more if you don’t have insurance. In 2019, reported pricing for the flu shot from $19.99 at Costco (no membership required) to $40.99 at Walgreens. If you have insurance, the flu shot is free in most cases thanks to mandates from the Affordable Care Act.

The nasal flu vaccine is a bit more expensive. lists prices for the Flumist vaccine that range from $29.99 at Costco to $34.50 at Walgreens.

If you’re weighing the upfront cost or the time and inconvenience of going to a clinic or pharmacy to get vaccinated, consider how much you might spend if you fall ill with the flu.

  • Doctor’s Visits. Prices for an uninsured doctor’s visit vary widely nationwide. According to a 2016 study published in the journal Health Affairs, an average office visit costs $146, while the Health Care Cost Institute put this average at $106 in 2016. And according to Chicago-based outplacement firm Challenger, Gray & Christmas statistics cited by the University of Utah Health, in the year the data was collected, the average person spent $130 treating the flu.
  • Hospital Stays. Costs can quickly turn astronomical if you develop complications from the virus and go to the hospital, especially if you’re uninsured. A 2019 analysis of data from 2006 through 2016 by The Healthcare Cost and Utilization Project estimates you’ll spend around $17,300.
  • Medication. Many people purchase over-the-counter medications to help ease flu symptoms. Popular medicines like Dayquil and Nyquil cost between $8 and $16 per bottle. Other treatments, such as VapoRub, cost around $5 each. Additional purchases, such as humidifiers to help ease congestion, Epsom salts to relieve muscle aches, or facial tissue will cost even more.
  • Lost Productivity. You also need to factor in the time lost at work or school. A 2007 study published in The BMJ estimates that seasonal influenza costs the U.S. economy $90 billion each year, with 44 million working days lost each year. The Challenger, Gray & Christmas statistics show employees without paid time off (PTO) lose an average of $92 a day when they call in sick, and the employers of those who have PTO lose $135 per day. But the 2012 Vaccine study shows it may cost more if your child gets sick. It found that parents who had to bring their children to the emergency room missed 19 hours of work, costing $383, while parents who treated their children at home missed 11 hours of work, costing $222. Parents with children hospitalized from the flu missed 73 hours of work, costing $1,456.

4. Might Lower Risk for Other Diseases

According to UTHealth News, Albert Amran, a fourth-year medical student with McGovern Medical School at The University of Texas Health Science Center at Houston, presented his research at the 2020 Alzheimer’s Association International Conference. Amran found an association between the flu vaccine and a lowered risk of Alzheimer’s disease later in life.

Amran and his team looked at more than 310,000 patient records and discovered that patients who received at least one flu vaccine in their lifetime were 17% less likely to develop Alzheimer’s. Amran’s research team also found that more frequent vaccines and getting the vaccination younger in life further lowered the risk of developing Alzheimer’s.

Cons of the Influenza Vaccine

There are some potential downsides to getting the influenza vaccine.

1. Side Effects

You can experience some side effects from the flu vaccine. According to the CDC, some typical side effects include:

  • Sore arm or redness around the vaccination site
  • Low-grade fever
  • Headache
  • Muscle aches
  • Nausea

Common side effects with the nasal spray vaccine include:

  • Chills or fever
  • Aches
  • Runny nose or nasal congestion
  • Fatigue
  • Headache
  • Wheezing
  • Vomiting or diarrhea
  • Sore throat

2. Developing Guillain-Barre Syndrome

In 1976, the CDC linked the flu vaccination with Guillain-Barre syndrome (GBS). This disorder causes the immune system to mistakenly attack the body’s own nervous system. The Mayo Clinic lists the following symptoms:

  • Prickling or pins-and-needles sensations in the fingers, toes, ankles or wrists
  • Weakness in the legs that can spread upward in your body
  • Rapid heart rate
  • Double vision
  • Inability to walk steadily or climb stairs
  • Difficulty making some facial movements
  • Low or high blood pressure
  • Severe pain in some areas of the body
  • Difficulty breathing
  • Inability to control bladder or bowels

Although there is no known cure, most people recover from GBS. Some are left with lasting nerve damage.

Although there haven’t been any subsequent links between GBS and the flu vaccine since then, the CDC estimates that 1 to 2 people out of every 1 million vaccinated could develop GBS, which is extremely rare.

Where to Get a Flu Shot

There are several ways to find a flu vaccine in your area.

  • Call 211 or 311. Starting Sept. 1, 2020, NPR reports that you can call 211 or 311, depending on where you live, to get information on flu clinics and free or low-cost options for a vaccine.
  • Visit Your Health Department. Nationwide, local health departments will be offering flu vaccines to residents. You can find your nearest health department’s location through the National Association of County and City Health Officials.
  • Use Vaccine Finder. Vaccine Finder is a free online tool that helps you find specific vaccines in your area. The website allows you to search for specific vaccine types, such as the nasal spray or egg-free versions of the flu vaccine.

Final Word

If you decide to get the flu shot, the best time to get it is in the fall before the live strains hit the population hard. It takes two weeks after vaccination for your body to build up the antibodies it needs to fight off the live strains. The CDC recommends you get vaccinated by the end of October, before influenza cases begin to escalate. However, even if it’s later in the year, a flu vaccine still offers protection and possibly lessens the severity of symptoms if you fall ill.

Will you get a flu shot this year? What factors influence your decision?

Heather Levin
Heather Levin is a writer with over 15 years experience covering personal finance, natural health, parenting, and green living. She lives in the mountains of Western North Carolina with her husband and two young sons, where they're often wandering on frequent picnics to find feathers and wildflowers.

What Do You Want To Do
With Your Money?