Influenza vaccine (difference between quadrivalent and trivalent)

If you walk down the subway or down the street, you will hear a gurgling sound and many people are wearing masks. Even after the coronavirus pandemic, flu vaccination is still recommended.

Vaccination began in September of last year for children, pregnant women, and seniors over 65 years old, but healthy adults also need flu vaccination.

Let's look at the difference between trivalent and quadrivalent vaccines.

First, flu is an influenza virus, divided into types A and B, and there are several variants that are prevalent every year. There are three types of vaccines: trivalent and quadrivalent.

Type A flu is highly contagious and can generally affect many people, causing large-scale epidemics. In particular, if the type A flu variant becomes prevalent, it can cause serious situations if not treated sufficiently due to rapid onset of symptoms when infected.

On the other hand, type B flu is relatively less contagious than type A, and it is said that it shows mild symptoms in healthy adults.

Virus Type	Contagious	Symptoms
Type A influenza	High	High fever, cough, sore throat, muscle pain
Type B influenza	Low	Relatively mild symptoms

The trivalent vaccine is mainly provided to children, the elderly, and patients with chronic diseases, and can be administered to the general public at a low cost (KRW 10,000-20,000), but the quadrivalent vaccine has a relatively high preventive effect and is somewhat expensive (KRW 20,000-40,000).

Vaccine Type	Included Virus Types	Characteristics
Trivalent vaccine	2 types of type A virus, 1 types of type B virus	Basic preventive effect
Quadrivalent vaccine	2 types of type A virus, 2 types of type B virus	Expanded, higher preventive effect