With autumn well underway, many are preparing for the upcoming holidays, as the days grow shorter and the air grows colder.  But while the holiday season may be upon us, another season has also arrived – flu season.

One of the most effective ways people can combat the flu is to get the flu shot, which protects against several different strains of the virus.  The Centers for Disease Control and Prevention recommends that all adults between the ages of 18 and 64 should be vaccinated for the flu each year.

However, fears and misconceptions surround the flu vaccine, and only a third of recommended adults receive the shot each year, which can leave many people vulnerable to the illness.  Those who are unprotected also run the risk of spreading influenza to those who are most susceptible – children and the elderly.

In an attempt to calm people’s apprehensions about getting vaccinated and educate others about the seriousness of the flu, actor Chris O’Donnell has teamed up with Sanofi Pasteur, the manufacturers of the flu vaccine, to promote vaccination this flu season.  One of the biggest motivators for O’Donnell is keeping his children free from illness.

“We have five little kids – ages 13 to 4.  They’re just bringing stuff home every day, it’s crazy,” O’Donnell told FoxNews.com.  “We have a strep throat right now, we have an ear infection.  So if you can knock out the flu for a year, that would be a good thing.”

Being a naturally squeamish person (he fainted at the birth of his first child), O’Donnell always hated getting vaccinated himself.  So when the “NCIS Los Angeles” star spoke with his doctor about flu shot options, he was excited to hear about the new FluZone Intradermal Vaccine.  Touting an ultra-thin microneedle 90 percent smaller than the typical vaccine, the shot only penetrates the skin’s surface, providing equally effective protection against the flu.

“It’s like a finger prick.  It’s preloaded, and it’s very fast,” Dr. Carlos Picone, vice-chair of the department of internal medicine at Sibley Memorial Hospital and a partner in private practice with Chevy Chase Pulmonary Associates in Washington, D.C, told FoxNews.com.  “You do not need to aspirate back.  When [needles] go into the muscle, frequently you need to make sure that the needle is in a blood vessel.  Here, it’s just bang, [and it’s done].  So it’s convenient.”

A recent telephone survey of 663 adults found that while 67 percent of adults are concerned about spreading the influenza virus to their loved ones, 61 percent of those surveyed remained unvaccinated.  Many reported that if the size of the needle were smaller, they would be more inclined to get the shot.

O’Donnell noted that many other misconceptions surround the flu shot.  For example, some believe that since the vaccine contains a variation of the flu, you can potentially contract the influenza from the vaccine.  According to Picone, it is impossible to get the flu from the shot.  He also noted that it is still possible to get the flu after getting the vaccine, because the vaccine is not 100 percent protective.

“The virus is a segmented virus and it will mutate, and it will rearrange,” Picone said. “That can happen anytime throughout the season…So as the shifts that the virus develops become more significant, the efficacy of the vaccine may decline.  So an efficacy of say 90 percent may go down to 50 percent.  But even if you develop disease, it won’t be as severe as if you had not been vaccinated.”

According to O’Donnell, another misconception people have is that getting the vaccine a year ago will continue to be protective.  However, like Picone said, the virus is constantly evolving.

“It’s a different strain every year,” O’Donnell said.  “They’re coming up with a different recipe every year because it’s a different strain of the virus.  So you really need to make sure you do it every year…And even if you don’t do it right now, you can still do it in the winter, in the spring, and it can still be effective.”

Given the significant number of people who suffer from the flu each year, both O’Donnell and Picone agree that it’s extremely important for people to have a better understanding of the flu vaccine and how beneficial it is for public health.

“A couple 100,000 people a year are hospitalized [for the flu].  Anywhere from 5 to 20,000 people die every year,” O’Donnell said.  “[These are] substantial numbers and it really can be dangerous for very young children and the elderly so it’s the responsibility for our group to kind of get out there and make sure that we go out and get our shots.”

“If you are a human being older than 6 months of age, you should be vaccinated,” Picone said.  “If more people get vaccinated in the community, then we can reach this so-called herd immunity.  But in order to have herd immunity, we need to reach penetration of 80 to 90 percent, and…we’re in the 30s.  We have a long way to go.”