Problem: I agree with you that immunization is crucial in preventing infectious diseases and increasing life expectancy within a population because Infants or toddlers are vulnerable to infections they and they need to be vaccinated, in order to protect them from the dangerous diseases like measles, chickenpox, smallpox, etc. Vaccination prevents varieties of diseases, thereby reducing mortality rate within a population. Failure to vaccinate a child may expose him or her to so many infectious diseases. Also, the elderly with an underlying chronic health issues and pregnant women are also among the vulnerable population who needs to be vaccinated and protected from infectious diseases.