Cedric has a low fever and minor aches. yesterday, he went to the doctor for his booster shot and received the flu shot. which best explains why he has this reaction? a. cedric was given an antibiotic. b. cedric was too old for the vaccine. c. the weakened virus stimulated the immune response and resulted in the minor reaction. d. the vaccine contained antibodies that caused cedric to make more antibodies.

The right answer is C.

There is a much higher risk of severe complications from influenza than of vaccine-related adverse events.

Of these adverse effects, the most common (for 10-40% of people vaccinated) is redness or pain at the injection site. Other symptoms can also be observed in 5 to 10% of the vaccinated: fever, muscular pain or slight nausea.

These reactions are benign and disappear at the latest after a few days.