According to the Centers for Disease Control and Prevention, on average 5 to 20 percent of the population in the U.S. gets the flu each year. More than 200,000 people are hospitalized from seasonal flu-related complications, and anywhere from a few thousand to 50,000 people die each year from flu.

The best way to prevent getting the flu, says the CDC, is by getting a seasonal flu vaccination each year. But do the benefits of getting the flu shot far outweigh the risks? Can potential lethal illnesses manifest years later in life, a direct result from getting yearly flu shots?

The truth about getting the flu vaccine is difficult to ascertain, with opinions about its safety differing widely depending on which medical professional you ask.

The flu shot does not give you the flu, most of the time

One thing both proponents and opponents of the flu shot agree on is that there are a few different types of flu vaccines, and sometimes, adverse side effects do occur from the shot.

Currently, there are four types of flu vaccines on the market:

  • A standard flu shot
  • A high-dose flu shot for those 65 and older
  • An intradermal-administered shot for those who are needle-phobic
  • A nasal spray
Contrary to what many people believe, the first three vaccines listed above do not contain the live flu virus.

“The vaccine is taken from two of the hundreds of different proteins that compose an influenza virus,” says the Mayo Clinic and Infectious Disease Society of America's Dr. Greg Poland. “Taking merely two surface proteins off the virus does not mean it’s live; there’s no organism there … it’s not possible to cause infection or disease with it … the flu shot does not give you the flu,” adds Poland.

As for the nasal spray, which does contain live flu viruses, Dr. Dan Harper, who is against vaccinations of all kinds, is especially leery of this methodology.

“You have 100 million viruses sprayed up the nose, along with other things like MSG (monosodium glutamate) and sugar, which causes inflammation. And since the virus also contains egg [proteins], you run the risk of introducing an avian retrovirus, which can cause encephalitis in humans.

“And so here you are spraying this up into your nose, just a few millimeters from the brain with MSG traveling across the blood-brain barrier, causing potential damage to neurotransmitters,” says Harper, who is based Solana Beach, Calif.

Does the government conclude that flu shots are 100 percent safe and effective?

No, but close to it, though adverse side effects have been documented in peer-reviewed medical journals. For example, a study in Human and Experimental Toxicology reported that there were 590 fetal-loss reports per 1 million pregnant women vaccinated (or 1 per 1,695) during the 2009-2010 flu season (generally regarded as October-March, though flu symptoms can occur any time of the year). The adverse events were tracked by the appropriately named Vaccine Adverse Event Reporting System, or VAERS, database.

In a review of vaccines conducted by researchers at the Institute of Biosecurity at St. Louis University, the co-authors concluded, “Vaccination remains a critical intervention during pandemics, but current production technology requires several months to develop sufficient vaccine to meet anticipated worldwide need…. Vaccines for use … during an epidemic are in development but … logistical obstacles to timely distribution exist [though] intensive research is underway to identify a universal vaccine.”

The Institutes of Medicine released a consensus report last year, which concluded that despite 135 vaccine adverse events in the study, few health problems are caused by or clearly associated with vaccines, including the flu shot.

According to most peer-reviewed research, the chances of encountering problems are statistically minimal; however, possible adverse effects from flu vaccine documented in medical literature include:

  • Febrile seizure
  • Narcolepsy
  • Asthma
  • Guillain-Barré syndrome
Humane reasons to get the flu shot
Some medical professionals, such as Dr. Elizabeth Baorto, division director of Pediatric Infectious Disease at Goryeb Children’s Hospital in Morristown, N.J., strongly believe that with rare exception — such as someone with an egg allergy — everybody 6 months and older should get a flu shot every year.

“Protecting oneself is an altruistic act. By getting vaccinated, you not only protect yourself, but you protect those around you as well,” says Baorto. “We are fortunate that we have a cheap and effective way of protecting ourselves with the flu vaccine.”

Will the flu shot protect you from a superbug pandemic outburst?

Not according to the aforementioned ardent vaccine opponent Harper (who is on the board of the nonprofit, Price-Pottenger Nutrition Foundation), who himself contracted polio in 1952, was paralyzed for seven years, and has seven children, none of whom have ever been vaccinated.

Harper thinks the flu vaccine lacks efficacy because the CDC has to guess which strain of influenza will be dominant in a particular year and it doesn't always guess correctly.

“[The CDC] only choose three to five strains of influenza A out of 250-plus strains, and they take only two or three influenza B strains out of 75-100 that are out there at any one time. If they don’t guess the right one, you’re going to get sick. You’re putting your faith in the CDC’s ability to guess the one that might be a pandemic.”

So, is it in your best interest to get the flu vaccine, regardless if a superbug is headed our way?

Poland unequivocally thinks so. “Which risk would you take?” he asks: “One in a million of a side effect or a one in 10,000 risk being hospitalized or dying. Flu-related illnesses cost the U.S. $90 billion a year, or almost one percent of GDP,” adds Poland.

But in contrast, Harper believes the risks of the flu shot far outweigh any benefit.

He claims that formaldehyde is an ingredient in the common flu shot and is a known carcinogen. “Another ingredient in the flu shot, thimerosal, contains mercury, which is known to impair neurological and immune systems. There are detergents, antibiotics, chemicals and allergens like polysorbate-80 that causes infertility,” adds Harper, along with other ingredients he deems unsafe for human consumption.

Indeed, the CDC does list some of these ingredients on its website. But the CDC claims, that at least in the case of thimerosal, “There is no evidence of harm caused by the small amounts of thimerosal in flu vaccine.”

Still, Harper is not convinced: “Someone who gets vaccinated could say, ‘Well the flu didn’t kill me.’ But when you’re sitting there with Alzheimer’s, ALS, MS or you’re watching your kid develop seizures or become autistic you’re going to kick yourself in the butt for allowing your child or you yourself receiving it. It’s frightening to me the stuff they put in the vaccine. These diseases, at least in part, are because of vaccines,” concludes Harper.

Do you think the flu vaccine is safe? Join the conversation in the comment section below.

Judd Handler is a health writer in Encinitas, Calif., and the author of "Living Healthy: 10 Steps."

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