Final answer:
The nurses do not have to obtain orders from each patient's physician for flu vaccinations because it is recommended for everyone and is especially important for high-risk individuals.
Step-by-step explanation:
The reason the nurses do not have to obtain orders from each patient's physician for vaccinations each year is because the flu vaccination is recommended for everyone who is at least 6 months of age. The vaccine is especially important for people who are at high risk of developing serious complications if they get sick with the flu, such as those with certain medical conditions, pregnant women, and the elderly. Therefore, it is a standard practice to administer the flu vaccination without needing individual orders from each patient's physician.