(CNN) - The aches, the sneezing, the sore throat, the exhaustion -- flu season is here, and you want to be prepared.
Typically, the "season" starts in October, but there has already been flu-related deaths reported. Physicians say it's not too early to get a flu shot, and they are available at many pharmacies and doctor's offices around the country.
The US Centers for Disease Control and Prevention recommends that people get a flu vaccine by the end of October, if possible. Doctors say you definitely want to get one before Thanksgiving, when you are likely to see more people, travel and be exposed to more germs. It typically takes about two weeks to build up your immunity once you get the shot.
Last year's flu season
For the 2018-2019 US flu season, which started October 1, 2018, and ended May 4, preliminary numbers from the CDC estimate there were nearly 42.9 million cases of flu, up to 647,000 hospitalizations and up to 61,200 flu deaths.
It wasn't a typical flu season, experts said. The severity was moderate, the CDC reported, but it was record-breaker as the longest flu season in a decade.
"Last year was funny in a way," said Dr. William Schaffner, National Foundation for Infectious Diseases medical director and professor of preventive medicine at Vanderbilt University Medical Center. "We had an unprecedented event with one virus dominating the season early on, then it abated, then another strain came along, making this a double-barrel season that we hadn't seen before and also making it rather prolonged."
Predicting the flu this year
For this year, the "crystal ball is very cloudy," about how bad it will be, but flu season is "not good for anyone," Schaffner said -- especially for the very young, pregnant women, the elderly and people with chronic conditions. All are vulnerable to the worst effects of the flu.
"One sure thing about influenza is, where and how it will spread or what kind of season we will have, it is unpredictable," said Dr. Daniel B. Jernigan, the director of the influenza division at the National Center for Immunization and Respiratory Diseases, a division of the CDC. "The more we know, the more we know you can't figure it out very well."
Jernigan said the CDC has increased the number of viruses it tests for and it works with scientists from all around the world to track them. Using sophisticated artificial intelligence and modeling they can characterize where the virus is going and what kind of virus it will be to some extent. But it's not easy, since the virus changes every year as it moves through the population.
The virus also can change within a season as it moves from country to country. Looking at how bad a flu season was in Australia, which has winter when the United States has its summer, is not necessarily predictive of what the flu season will be like in the U.S., Jernigan said.
"This virus continues to be elusive," Jernigan said. "While we don't have a clear idea, we do know flu is going to be here and the best way to prevent it is to get a vaccine."
"We get on our soapbox and remind people that everyone older than 6 months needs to be vaccinated every year," said Schaffner.
Get your flu vaccine
It's not a perfect vaccine because there are a number of flu strains that circulate, but it does provide some protection. If you happen to get sick, the vaccine cuts down on how long your symptoms last and it should protect you from the major complications that come with the flu, such as pneumonia.
"What the vaccine does is shift the equation in our favor," said Schaffner.
This year, nasal spray is an option for some patients, including children who may not like getting a shot. In some years, the American Academy of Pediatrics recommended children stick with a shot, as some studies showed it was more effective. There is no such suggestion this year.
The time get the shot is now
Schaffner adds that if you have a chronic disease such as diabetes or asthma or heart disease, the flu shot should be a part of your regular care. In that case, you are the kind of patient that the flu makes very sick and you are at highest risk for hospitalization and death. The flu can also put you more at risk to have a heart attack or a stroke.
With some older people, doctors might recommend they get the vaccine in the middle or end of October, because their immunity could wane toward the end of the season. But Dr. David Cennimo, an infectious disease specialist and assistant professor in the department of medicine at Rutgers University, said he usually tells his patients to get it whenever they can.
"If they are really concerned about the potential for the vaccine to wane over six months, they may want to wait a few weeks but you really don't want to go beyond middle October or the end of October, because of the risk of exposure to flu in your area," said Cennimo.
What else can you do to avoid the flu?
There are ways to avoid the flu.
Repeatedly washing your hands can help protect you this flu season. Flu germs tend to linger and hand washing can cut down our exposure.
Avoid friends and family members that are sick.
And for the sake of those around you, stay home from work or school if you are sick. Rest will help you get better and staying home can protect people around you.
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