Flu shots, otherwise known as flu vaccines or influenza vaccines, are vaccinations to help prevent some strains of influenza (the flu). They are annual vaccines, which means they must be given every year.
Flu shots help protect people from getting influenza. Influenza is a virus that can make people very sick. It also makes you more susceptible to getting other infections, called secondary infections. Most people who get the flu recover completely within a week or two; however, many thousands of people die from influenza and related complications every year.
Flu shots are different almost every year. Experts around the world work together to try to figure out which strains of influenza are most likely to circulate in the following year. Then they use those strains in the vaccine. Because flu viruses mutate quickly, the flu vaccines only offer protection for about six months. That’s why it’s important to get one every year.
Most people should get flu shots
The Centers for Disease Control (CDC) recommends that every person over the age of 6 months get an annual flu shot with few exceptions (like allergy or a history of severe adverse reaction to a flu vaccine).
Pregnant women should always get a flu shot. They are more susceptible to getting influenza, and if they do get sick, it can be dangerous to both them and their baby.
People who are at high risk for serious complications of the flu should be vaccinated if possible. This includes young children, people over the age of 65, pregnant women, residents of nursing homes and other long-term care facilities, people with health conditions, such as asthma, chronic lung disease, heart disease, liver and kidney disorders, diabetes, blood disorders, and people with weakened immune systems due to illness or medication.
People who care for infants less than 6 months of age should always get their flu shots to protect their children from exposure. The same is true for people who live with or come into close contact with those at high risk for serious complications of influenza.
People who should not get flu shots
There are some people who shouldn’t get a flu vaccine. For example, people with certain allergies and people who have had Guillain Barre syndrome (GBS) within six weeks of getting a flu vaccine may not be able to have flu shot. Babies under 6 months of age shouldn’t get it. And anyone with a fever over 101 degrees F should wait until they’re fever free before getting the vaccine.
But for the vast majority of people, the flu vaccine is safe and effective. If you’re worried, talk to your primary care doctor about any concerns you have about the vaccine before you get it. And if your doctor clears you, get your vaccine.
Reasons to get a flu shot
There are several reasons to get a flu shot. First, it helps protect you against the flu and complications of the flu. It can also offer you some protection if you are infected with a strain of the flu that wasn’t covered by the shot. Experts say having the flu shot is likely to reduce the severity of any flu strain you get even if it wasn’t one of the strains in the vaccine.
The flu shot also helps protect the people around you. If everyone who could get a flu shot did, serious illness and death from influenza would decrease dramatically. There are some people who are at high risk for getting very sick or even dying from the flu and its complications. Some of those people cannot get the flu shot. When others around them get the shot, it helps protect the vulnerable people. This is called herd immunity.
Influenza is a serious, potentially deadly disease. Every year, between 5 and 20 percent of people in the United States are diagnosed with the flu, and it likely affects many more of us. It can lead to serious complications.
More than 200,000 people in the U.S. are hospitalized every year due to the flu and its complications. Tens of thousands die. And it’s not always elderly people. Every year, children and young adults die from the flu too.
Flu season usually starts in late fall, peaks in the winter, and fades out by the spring. The height of flu season is usually in December or January.
Infectious disease experts have been warning of a flu pandemic for years. You may have heard of the 1918 flu that infected about 500 million people around the world and killed between 20 and 50 million people. Nearly 700,000 of those people were Americans. Think about how the population has grown since then. If we have another pandemic like that one, which experts believe we’re long overdue to have, the flu could kill millions of people. We have more effective medical care now than we did a century ago, and we have the flu vaccine. But a flu pandemic could still be devastating.
Preventing the flu
The best thing you can do to prevent the flu and to be part of a greater community prevention is to get the flu vaccine. It’s also important to do the following:
- If you’re sick, stay home. You will be contagious for at least a week, so stay home as long as you can to avoid infecting others. Remember, people die from the flu, so your decision to go to the grocery store or school or work when you’re sick could end up infecting someone who might die from the virus. If you must go out while you’re sick, stay as far away from people as possible, and consider wearing a surgical mask. No matter what, remember to cover your mouth and nose completely if you cough or sneeze. Just putting your elbow or hand near your mouth will not keep the flu virus from spreading. Your nose and mouth must both be completely covered. Use a tissue if you can, or consider pulling your shirt over your face if you cough or sneeze. Then clean your hands so you don’t spread the virus through whatever you touch.
- Practice good hand hygiene. Wash your hands before you eat or touch your face and after you cough or sneeze.
- Keep your surroundings clean. If someone in your house is sick, sanitize doorknobs, faucets, toilets, light switches, remote controls, cabinet doors, the refrigerator – anything the sick person may touch.
- Stay away from people who are sick if possible. If someone in your house is sick, think about keeping him or her isolated. If that’s not possible, consider a surgical mask to protect others in the home.
- Eat a healthy diet and exercise. If your overall health is good, you’re less likely to get sick.
- If someone in your house is infected, talk to your doctor about getting him or her a course of antiviral medication. Others in your household may want to take it preventively as well – especially if they are at high risk for complications of the flu.
When to get a flu shot
Get your influenza vaccine every year. The vaccine changes from year to year as the viruses circulating mutate, so it’s important to get a flu shot annually.
The best time to get a flu vaccine is in the fall before influenza starts spreading through the community. Because the vaccine takes weeks to be fully effective, you’re less likely to catch the flu if you get your vaccine early. Many doctor’s offices and pharmacies start giving the flu vaccine in early September each year.
The best time to get a flu shot is in September or early October. That said, it’s better late than never when it comes to flu vaccines. You can get your vaccine as long as the flu is circulating (even as late as May). It’s just not as likely to protect you from the height of flu season if you wait until the season is almost over to get your vaccine.
Getting the vaccine after a flu
If you get the flu before getting the vaccine, you may still want to get your flu shot. This is because there are multiple strains of the flu, so getting one only gives you immunity to that strain. You will still be vulnerable to other strains. If you get the flu shot, you will have protection against three or four strains.
Can the flu shot make me sick?
Influenza vaccines cannot give you the flu. They cannot make you sick with the flu, and they cannot give you any other strains of the flu. All flu shots are made with an inactivated form of influenza viruses. These viruses are not live, and they cannot make you sick. The shot works because your body recognizes the inactivated viruses in your body and begins to make antibodies against those viruses. Once you have antibodies to a specific virus, your body is able to fight off the virus if it enters your body.
Some people believe that the flu vaccines made them sick or gave them the flu, so they are hesitant to get the vaccine. While they may have gotten sick and they may have even gotten the flu after getting the vaccine, the vaccine did not make them sick. There are a few reasons people sometimes get sick after a flu vaccine:
- They got sick from a virus or bacterial infection not covered by the vaccine.
- They got the flu before their bodies had antibodies against the flu. Because it takes the body several weeks to develop immunity, it is possible to get the flu between the time you get the shot and the time you develop immunity.
- They got a strain of influenza that wasn’t covered by the flu shot.
- Their body didn’t develop complete immunity to the flu viruses in the vaccine, so they developed one of the strains of the flu covered by the vaccine.
Doctors believe that the flu vaccine offers protection from many strains of the flu, and it may even protect you if you come in contact with a strain of influenza virus that isn’t part of the vaccine. If you get a strain of the flu covered by the vaccine, you could still get sick, but you will likely have a much milder case, and you won’t be as likely to experience secondary infections and other serious complications of influenza.
The prevailing medical consensus is that the influenza vaccine does a good job of protecting people from influenza.
Risks of the flu shot
Flu shots are generally safe. You’ve probably heard rumors that vaccines can cause autism or that there is mercury in flu shots that’s dangerous or the flu shot can make people sick. Those things are not true. Here are the facts:
- Influenza vaccines cannot and do not cause autism. Just because people report that their children developed autism after a vaccine does not mean the vaccine caused it. There is no evidence that vaccines cause autism, and there is lots of evidence that they don’t.
- Single-dose flu vaccines do not contain any mercury. The concern about mercury is related to thimerosal, a type of preservative. Even multi-dose vaccines are safe. But if you are worried about your child being exposed to thimerosal, ask for a single-dose vaccine.
- Influenza vaccines do not give people the flu. People may be infected with the flu before they get the vaccine and may develop flu symptoms shortly after getting the vaccine. Or they may get the flu in the weeks after the vaccine is administered but before the body has had a chance to make enough antibodies for immunity. And people can get strains of influenza not covered by the shot. It’s those people who believe they got the flu from the shot or that the shot doesn’t work. They are misinformed. The flu shot can’t give you the flu, and the flu shot does work. Some years it doesn’t work as well as others, but it’s always better to get the shot than to forgo it.
- Influenza is a serious and potentially deadly virus. It’s also highly contagious. Many people believe it’s not a big deal if they get the flu, so they won’t bother with the vaccine. It’s true that most people recover fully from the flu in a week or two. But many people are hospitalized and die every year from the flu, including children. Children, elderly people, and people with weakened immune systems are especially at risk, but even otherwise healthy people can and do die from the flu. It is a big deal. It is dangerous. And it can kill you. The best way to protect yourself, your family, and other people in your community is to get the flu shot every year. The second best thing you can do is to stay home if you get sick so you don’t spread the virus to others.
Where to get a flu shot
Flu shots are available in many places. For example, you may be able to get a flu vaccine at:
- Your doctor’s office
- A pharmacy
- A flu clinic
- An urgent care center
- The hospital