Types of Flu Shots, Effectiveness, Side Effects & More

In the United States, the flu season is from October to May. Therefore, physicians often recommend that everyone, especially those most at risk for the flu, get the vaccine as early as October. As you know, the flu is a very contagious disease. These days, getting the flu vaccine is even more important due to the prevalence of COVID-19.

If you live in Las Vegas, you can go to the Southern Nevada Occupational Health Center to get the flu vaccine. Our specialists at this center will give you the most compatible type of vaccine based on your age, health condition, and history of allergies.

As you know, different flu vaccines are available in the pharmaceutical market. What is the difference between types of flu shots? Do they have an advantage over each other? Which vaccine should be given? Can people who are allergic to eggs get the vaccine? Join us to answer these questions in the next sections.

Types of Flu Shots

Influenza vaccines produce antibodies in the body within two weeks. These antibodies protect you from getting infected. Fortunately, there is more than one flu shot available in the United States, and no preference is defined for any influenza vaccine over another.

Influenza vaccines or flu vaccines fall into two general categories:

• Trivalent flu vaccines
• Quadrivalent flu vaccines

Types of Flu Shots: Trivalent

These vaccines protect you against three strains of the flu virus:

• influenza A (H1N1)
• influenza A (H3N2)
• an influenza B virus

These vaccines contain compounds that trigger a stronger immune response and are usually recommended for people 65 and older.

Types of Flu Shots: Quadrivalent

This vaccine protects you against four different flu viruses, including two influenza A viruses and two influenza B viruses. Influenza vaccines were produced as trivalent vaccines for many years, and their protection was effective against only three types of viruses. But quadrivalent vaccines provide broader protection against circulating flu viruses.

Quadrivalent vaccines do not cause the flu illness because they contain killed or attenuated viruses or are made using recombinant technology. Therefore, it can be said that these vaccines, like all influenza vaccines, are safe and are monitored annually in terms of safety and effectiveness.

• The standard-dose flu shot is produced using a virus grown in eggs and is approved for people six months and older.
• The quadrivalent cell-based influenza shot vaccine contains a virus grown in cell culture, which can only be given to people 4 years of age and older. In other words, these vaccines are considered egg-free.

• Recombinant quadrivalent influenza shot is an egg-free vaccine approved for people 18 years of age and older.
• Quadrivalent flu shot using an adjuvant also produces a stronger immune response and is prescribed for people 65 and older.
• Quadrivalent high-dose influenza vaccine is also for people over 65 years.
•  Live attenuated influenza vaccine is used intranasally, which is approved for people aged 2 to 49 years. The vaccine should not be used in pregnant women, people with weakened immune systems, and some other groups.

How to choose the right vaccine?

As you can see, there are several vaccines on the market. It can be said that these vaccines are not superior to each other. So if you have questions about choosing the right vaccine, you can talk to your doctor.

The three factors should be considered when choosing the type of flu vaccine:

• Person’s age
• Health condition
• Allergy to influenza vaccine and its components

Is the flu vaccine safe for people with egg allergy?

As you know, some types of flu shots contain small amounts of egg protein. If you are allergic to eggs, you may be hesitant to get the flu shot.

New research and achievements show that egg allergy is no longer a barrier to vaccination. People who are allergic to egg should be vaccinated in a medical setting, under the supervision of an experienced doctor who can identify and manage severe allergic reactions. In addition, two completely egg-free flu vaccine options are available:

• Quadrivalent recombinant vaccine
• Quadrivalent cell-based vaccine

How effective are the flu vaccines?

The CDC conducts annual studies to evaluate the effectiveness of types of flu shots. Research has shown that the effectiveness of influenza vaccines varies from year to year but generally reduces the risk of the disease by 40 to 60 percent during flu season when most circulating viruses are well-matched to the vaccine. In general, vaccines currently available provide better protection against influenza B and influenza A (H1N1) viruses.

Factors that determine how well the flu vaccine works are:

• Age and health status of the vaccine recipient
• Match between the flu viruses the vaccine designed against it

If the vaccine designed does not match with circulating influenza viruses, the vaccination will not work. In spite of a proper match between the circulating virus and the vaccine, the effectiveness of the vaccine is still influenced by other factors, such as the condition of the vaccine recipient.

Why do some people still get flu symptoms despite receiving the flu shot?

There are several reasons why people get flu symptoms despite being vaccinated:

• Keep in mind that the types of flu shots only protect you against the flu, not the common cold. Therefore, other viruses may be the cause of flu symptoms.
• As you know, two weeks after vaccination, antibodies are produced in the body. So you may have been exposed to the virus during the two-week period.
• You may have been exposed to a virus that is different from the virus the vaccine is designed to protect against.
• Finally, we must consider that types of flu shots vary in how well they work, and some individuals who get vaccinated still get sick.

Side effects of influenza vaccines

The side effects of the different types of flu shots are similar to those of other vaccines. Common side effects include:

• Soreness
• Redness or swelling in the injection site
• Headache
• Fever
• Nausea
• Muscle aches
• Fatigue
• Fainting (which rarely happens)

The good news is that the mentioned symptoms are often mild and go away on their own. Life-threatening allergic reactions to flu vaccines are very rare, and the new flu vaccines are designed to reduce the possibility of such reactions. However, if you have a history of severe allergic reactions, be sure to tell your doctor.

There is a small likelihood that the flu shot could be associated with Guillain-Barré syndrome; generally, less than 2 cases per million people vaccinated. This syndrome is a rare disorder in which the immune system attacks the nerves.

Let’s sum up

The flu vaccine is safe even for people ages six months. Fortunately, types of flu shots help your doctor determine the best option based on your health condition, age, and history of allergies.

If you have not yet received the vaccine, you can contact our consultants. We always improve our services based on the needs of our clients. Fortunately, all types of flu vaccines are available at this center. Our specialists will consider the most suitable vaccine for you based on your circumstances.