Flu specialists have stepped up their reminders about flu vaccines after fresh numbers showed the U.S. had its deadliest flu season in decades, with 80,000 people dead and a record number of hospitalizations.

Just about everyone is advised to get an influenza vaccine, and people need a fresh one every year.

Flu is a major killer. This past flu season showed just how bad it can get: the Centers for Disease Control and Prevention says flu killed 80,000 people in 2017-2018, including 180 children, and put 900,000 into the hospital.

Here's some guidance about flu vaccines:

Do I really need one?

The unequivocal answer is yes. Every major medical organization recommends getting a flu vaccine every year. Even if the vaccine doesn't completely prevent infection, it can make it less serious. “That old thing, ‘I got the flu shot and I still got the flu’? Well you know what? You didn’t die,” U.S. Surgeon General Dr. Jerome Adams said at a news conference in September.

According to the latest CDC numbers, fewer than half of Americans, about 47 percent, got a flu vaccine last year. The CDC recommends that people get a flu vaccine by the end of October.

I never get the flu, so why do I need the shot?

Influenza causes a range of symptoms and it doesn't knock everyone flat. People can have mild influenza and still function, going to work or school. But those people are spreading the virus to those who are more vulnerable. "Those 80,000 people who died from flu last year? Guess what? They got it from someone," Adams said.

Many of the people who die from flu every year, including young children, were perfectly healthy before they became infected. Plus, this could be the year you do get infected and miss two weeks of work, or worse, end up in the hospital.

Pregnant women, especially, need a flu shot. It can protect their babies when they are first born and pregnant women are especially susceptible to severe flu symptoms, in part because their immune systems are suppressed and in part because the growing fetus presses against the lungs. Flu in pregnancy can also cause miscarriages.

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Why not just wait until flu is circulating?

It takes about two weeks for the body to respond fully to a flu vaccine and develop immunity. Flu moves fast and could be spreading by the time people even think about getting vaccinated. Young children who are getting their first immunization need two doses, delivered at least four weeks apart.

What about FluMist?

The needle-free vaccine is back on the U.S. market this fall, re-formulated in the hope of making it more effective. It's a good option for needle-phobes, but pediatricians say kids should get a shot if possible and not the FluMist nasal spray.

FluMist is made using a "live" vaccine, so it's not approved for very young children, people over 50 or pregnant women.

When is too early to get a flu vaccine?

There's growing evidence that the efficacy of flu vaccines wears off after a few months, so that's a valid question. But there is no good answer yet. The CDC and other flu experts say it's best to get vaccinated by the end of October because that protects people before influenza starts spreading. The flu season usually peaks in January and February in the U.S. but flu is unpredictable and an early season could mean high activity by November.

Which vaccine should I get?

Americans have about a dozen different influenza vaccines to choose from, produced by seven different manufacturers. There’s a high-dose vaccine for elderly people and formulations approved for children and babies.

“CDC does not recommend one flu vaccine over another. The most important thing is for all people 6 months and older to get a flu vaccine every year,” the CDC says.

Most people don’t even know which vaccine they are getting, as clinics, pharmacies and doctors usually make their own arrangements with suppliers. But it's possible to ask.

One big hospital system, the University of Pittsburgh Medical Center, is providing egg-free vaccines this year: Flucelvax and Flublok. That’s because there is some evidence these two formulations may work better than the older vaccines grown in eggs.

There's a vaccine delivered using a jet injector instead of a needle, but the intradermal vaccine, which used a very short needle, will not be on the market this year.

Why is the flu vaccine so bad?

Most influenza vaccines are made using old technology that involves the use of eggs. There are several problems with using eggs to make vaccines, one of which is a mutation the current H3N2 flu virus gets when it is grown in eggs. It makes the virus harder for the human immune system to recognize and fight it.

The result is a flu vaccine that doesn’t offer much protection against that strain, although it protects a little better against H1N1 and influenza B strains.

One of the newer vaccines, Flublok, uses genetic material from the most common circulating flu viruses and combines it with an insect virus called a baculovirus grown in caterpillar cells. Another one, Flucelvax, is grown in canine kidney cells. Manufacturers hoped these processes would make them both quicker to manufacture and more effective.

What about flu drugs?

The CDC says vaccines are the best way to prevent flu but there are several drugs on the market that can treat it. Tamiflu is recommended for children and people who have a high risk of complications from flu, but patients must take multiple doses over several days. Relenza is less commonly used, but it and peramivir are more useful for hospitalized patients who may be unable to take pills.

There’s a chance a new one may hit the market before the end of the coming flu season. The Food and Drug Administration has agreed to fast-track consideration of baloxavir, which takes a new approach to treating flu. It also appears to helps control flu symptoms after one dose.