Why is it hard to make a good flu vaccine? a) vaccines take months to make, so people have to guess which strains of flu are going to be active long in advance. b) the vaccine makers cannot hire the most qualified employees because there is so little profit in making vaccines. c) most people do not get flu shots because they like having an excuse to take a day off. d)the public is uninformed about the way vaccines work, and they do not engage in healthy habits.

A) Vaccines take months to make, so people have to guess which strains of flu are going to be active long in advance.

One of the reasons why it is challenging to deal with the flu virus is that it is particularly versatile. Therefore, it is difficult to predict which strains of flu are going to be active in advance. However, this does not mean that the flu vaccine is useless. People that are immunocompromised or that work with vulnerable populations (such as children and the elderly) particularly benefit from the vaccine, as it prevents them from spreading the virus to those in their care.

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