Given a situation, please help me figure out the three following questions.

The government is able to distribute COVID-19 vaccines to all its citizens. However, it takes time, so some people might have to wait several weeks before getting their dose. In the meantime, the government is launching an advertising campaign around staying healthy, and improving one's immune system. In particular, it is worried about people with conditions such as diabetes, obesity, asthma or other cardiovascular problems. Assume that the vaccines are guaranteed and improving our immune system requires effort.

(1) Will the advertising campaign be effective?

(2)What is the potential problem called?

(3)Please discuss the efficiency of advertisements in relation to moral hazard.