ABSTRACT
Today, vaccines are required by payers, public health policy makers, and regulators to comply with the increasing standards of evidence-based prevention. It has also become harder to gain confidence from the society which becomes more concerned with vaccines’ tolerability and safety.2,3
The World Health Organization (WHO) defines a vaccine as “a biological preparation intended to improve immunity toward a particular disease.” The concept is based on stimulating the body’s immune system versus an agent that is similar to the disease-causing pathogen or its components. The agent delivered by the vaccine is often either an attenuated or inactivated form of the pathogen or one of its components. The immune system will react by recognizing and destroying this agent while keeping a more or less sustainable memory of this reaction. This memory would make the elimination of the pathogen easier and more effective during future contact(s).4
