Types of Flu Shots

When you’re planning your flu shot, considering your options can be confusing. If you have any health conditions, you can ask your doctor if specific flu vaccines are better or worse for your condition. For most healthy adults, all of the options that are available for getting the flu shot are safe and effective. 

The flu shot is recommended every fall, in advance of flu season, for all people who are 6 months of age or older, with few exceptions. The vaccine can help prevent you from getting sick from the common strains of flu that you could be exposed to.

The flu vaccine provides you with controlled exposure to common forms of the flu virus or its components. This triggers your immune system to recognize and fight the virus if you later become exposed. 

Types of Flu Vaccines 

The flu vaccines for the 2022-2023 season are quadrivalent formulations, meaning that they protect you from four strains of the flu virus. The strains included in each year's flu vaccine are determined based on which strains are most likely to be circulating and making people sick.

There are different ways to get the flu vaccine:

• Injected with a needle into the arm muscle
• Nasal spray
• A jet injector using a high-pressure, narrow stream of liquid to penetrate the skin without a needle

Flu vaccines are produced in several different forms:

• Live attenuated (weakened) virus grown in an egg-based material
• Inactivated virus grown in an egg-based material or cell culture
• Vaccines manufactured with synthetic material that uses recombinant technology

Some forms of the vaccine are available in more than one way of delivery. Check with your healthcare provider to determine which vaccine is available to you.

There are different brands of flu vaccines, which you may see at your doctor’s office or pharmacy.

Special Considerations

There are a few special considerations to keep in mind before you get a flu vaccine. Speak with your doctor for more personalized advice if these apply to you.

Healthcare Workers

If you are a healthcare worker, getting the flu vaccine on time can protect you, your family, and your patients.

If you work among people who are sick, you could have a higher exposure to the viruses that cause the flu. Additionally, if you are in close or frequent contact with people who have a weak immune system, you could expose them to the virus, and they could become very sick.

Pregnancy

It is particularly important that you get a flu shot if you are pregnant as your immune system can predispose you to infections. Although the risk is very low, getting a severe case of the flu can lead to pregnancy complications. If you are pregnant or think that you might become pregnant during the upcoming flu season, it is recommended that you get a flu shot.

The inactivated flu vaccine is preferred during pregnancy. The nasal spray flu vaccine should be avoided during pregnancy.

Health Conditions or Weak Immune System

Patients who have a severe chronic illness or an impaired immune system are generally advised to get vaccinated. A chronic illness or a weak immune system increases the risk of becoming very sick from community-acquired flu viruses.

Certain medications or chronic illnesses may make you immunocompromised. For instance, you might be immunocompromised if you are taking medication to treat cancer or immunosuppressant drugs for a condition such as rheumatoid arthritis or lupus, or if you have an immune system disorder, such as HIV/AIDS.

Chronic illnesses that can make you susceptible to severe illness from the flu include diabetes, kidney disease, heart disease, asthma, and neurological conditions.

Inactivated forms of the flu shot are recommended for people with chronic illnesses or weak immune systems. Make sure to speak with your doctor to determine if you should avoid the nasal spray flu vaccine.

Precautions and Contraindications

For some people, getting a flu vaccine has to be done with extreme caution. If you have an egg allergy or if you have had a reaction or allergy to a previous flu vaccination, talk to your doctor before you get the vaccine. You might be advised to get only certain forms of the vaccine or to be observed for complications after you receive the vaccination.

Egg Allergies

Some people can develop an allergic reaction to vaccines that are grown with an egg-based process. While this type of reaction is rare, the allergy can affect people who are allergic to egg-based products.

There are two types of flu vaccines that are not egg-based. If you are allergic to eggs, talk to your doctor about what type of flu vaccine you should receive.

If your only symptom of an egg allergy is hives, you may be able to receive any form of the flu vaccine. If you had symptoms other than hives when exposed to eggs, your doctor may recommend you get vaccinated in a medical setting under the supervision of a medical professional who can recognize and treat any serious reaction.

The effects of a serious allergic reaction to a flu vaccine usually begin within a few minutes to a few hours after receiving the vaccine. Symptoms can include:

• Difficulty breathing
• Hives
• Pale skin
• Feeling weak
• Rapid heartbeat
• Dizziness

You should get urgent medical attention if you develop any signs of a serious allergic reaction.

Vaccine Allergy

If you have had an allergic reaction to a flu vaccine, you need to talk to your doctor about the symptoms you experienced before getting vaccinated. You might be advised to have a certain form of the vaccine.

If a previous flu vaccination resulted in a severe, life-threatening allergic reaction, getting a flu vaccination is not recommended.

Guillain-Barré Syndrome or CIDP

Guillain-Barré syndrome (GBS) and chronic inflammatory demyelinating polyneuropathy (CIDP) are rare conditions that cause severe weakness of the legs and the muscles that control your breathing. It is rare and is seen to occur after bacterial or viral infections (including influenza).

Some people who have these disorders can have flare-ups after the immune system is stimulated by an infection or a vaccine. If you have ever had these syndromes, talk to your doctor about your vaccine risks and how to stay safe from the flu.

The Centers for Disease Control and Prevention monitors for cases of GBS each flu season. They have not seen consistency of occurrence during different flu seasons. If there is an increased risk of GBS after flu vaccination in any year, it is tiny, amounting to an additional one or two cases per million doses of vaccine.

Side Effects

Many people do not have any side effects from the flu vaccine, however, some mild, and temporary effects may occur. These generally begin between six to 12 hours after getting the vaccine, and typically last for one to three days.

Common side effects include:

• Soreness, redness, and/or swelling on injection site
• Mild to moderate headache
• Fever
• Nausea
• Muscle aches
• Fatigue

These side effects are not the same as an allergic reaction. Side effects after the flu vaccine occur because the immune system is working in response to the vaccination.

Summary

The influenza vaccine can protect you from getting the flu and the risk of experiencing severe complications. There are different types of the flu vaccine that can be inhaled or injected, as well as those developed from live viruses, inactivated viruses, or synthetic viral components.

Most people can receive any type of flu vaccine. Your doctor can advise if you need to avoid one type due to an underlying condition or allergy.

A Word From Verywell

The flu is common, contagious, and can cause illness ranging from a few days of feeling run down to severe pneumonia. Getting a flu vaccination is an important aspect of staying healthy.