No, it is not a reasonable gamble for Karen to skip the influenza vaccine this year.
There are many factors which can increase a person's risk of developing the influenza virus and some of these factors are age, health condition, weakened immune system, pregnancy, or chronic illnesses.
Karen is older and her age could act as a risk factor for influenza. In addition, each year there are different strains of the virus since the virus is constantly changing and evolving. Given this, a person who got the vaccine last year is still in danger of not having the antibodies which can protect from this year's strain.
Karen should get the influenza vaccine this year as well.
Viruses are similar because they move around freely.
Activation energy is the minimum quantity of energy that the reacting species must possess in order to undergo a specified reaction.
for example , striking a match on the side of a matchbox provides the activation energy, in the form of heat produced by friction.
I can help you if you show the word bank
