This post contains material from a story published in October 2019.

Flu season is ramping up in New Jersey, as activity is now widespread in all regions of the state.

Emergency room visits and admissions have surged in recent weeks, topping the three highest flu seasons ever recorded in the state at this point of the year, according to the latest data from the New Jersey Department of Health.

“There is definitely an uptick in influenza cases, and visits are up,” said Dr. Chris Freer, chairman of emergency medicine for Saint Barnabas and system director of RWJBarnabas Health Emergency Services.

Freer said from here on out, the season will only intensify. He estimates flu activity will remain high for at least the next six to eight weeks.

Here’s what you should know about this year’s flu and how to protect yourself:

What’s the dominant virus this year?

The predominant flu strain this year is influenza B. There are four different types of flu viruses: A, B, C and D. Each season, one strain ends up causing the bulk of illnesses.

How bad has the season been so far?

There were 1,455 cases of influenza B reported statewide, according to the state Health Department’s latest flu surveillance report. Two weeks earlier, just 422 cases were reported.

There’s also been one flu-related pediatric death so far this season.

Though influenza A strains — like H1N1 (swine flu) and H3N2 — are the only viruses known to cause flu pandemics, influenza B can still be severe, according to the Centers for Disease Control and Prevention.

Since the flu is unpredictable, it’s difficult to forecast how severe a given influenza season will be. Last year’s flu season was one of the deadliest in years. Only time will tell how this year will unfold.

What’s new with the vaccine this season?

The good news is the vaccine was manufactured to better match this season’s anticipated flu strains, which also include H1N1 (swine flu) and H3N2. The shots were also grown in cells instead of eggs (the primary way to manufacture vaccines in the past). Growing the vaccine in cells has “potential to offer better protection than traditional, egg-based flu vaccines as a result of being more similar to flu viruses in circulation,” according to the CDC. In the past, some strains, especially the H3N2 virus, mutated while incubating in the eggs.

Freer urged people to get vaccinated if they haven’t already and to practice proper hygeine, like washing hands.

What are the flu shot options this season?

• Standard dose: A shot administered into the muscle, usually with a needle.
• High-dose shots: For people 65 years and older.
• The nasal spray vaccine is also being offered.

How long does it take for the vaccine to work?

After receiving the vaccine, it takes roughly two weeks for your body to create the antibodies needed to protect against the flu.

Do some children require two doses of flu vaccine?

Some children 6 months through 8 years of age will need two doses of flu vaccine this season, according to the CDC. For more information on who should get a second dose, click here.

Who is most vulnerable to the flu?

Though the flu is typically not severe, it can be life-threatening. Young children and older adults are among the most vulnerable.

Most people should get a flu shot. However, the vaccine is not recommended for some people, including children younger than 6 months old and people with "severe, life-threatening allergies to flu vaccine or any of its ingredients," according to the CDC.

What are the symptoms of the flu?

According to the CDC, symptoms of the flu include:

• Fever, or feeling feverish/chills
• Cough
• Sore throat
• Runny or stuffy nose
• Muscle or body aches
• Headaches
• Fatigue (tiredness)
• Vomiting and diarrhea (however, this is most common in children, the CDC says).

How effective was last year’s flu shot?

Last year, the vaccines for influenza A or B strains were only 29% effective. For H1N1, it was around 44%. And for H3N2, the effectiveness was about 9%.

What are some common myths and misconceptions about the flu shot?

• Myth: The flu vaccine can give you the flu. (False. In extremely rare cases, however, some people can develop a life-threatening reaction, according to the CDC.)
• Myth: It’s better to get the flu than the flu vaccine. (False, unless you like getting the flu.)
• Myth: I don’t need a flu shot every year. (False. The flu vaccine will eventually wear off, which is why you should get one every year.)

Spencer Kent may be reached at skent@njadvancemedia.com. Follow him on Twitter @SpencerMKent. Find NJ.com on Facebook.

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