Our bodies have a way of fighting with foreign bodies, which causes us diseases. The immune system identifies when foreign bodies (immunogens/antigens) enter our systems and our bodies start to form defense molecules (antibodies) in order to protect us from harmful and deadly diseases. Mostly these foreign bodies are bacteria, viruses, or toxins. These agents enter our bodies through mouth, nose, eyes, skin etc. when the natural protecting substances like tears, saliva, and acidic gastric juice cannot kill them. Most of these pathogens are very effective, and natural immunity may not be adequate. Vaccination and immunization are related to this defense system. The two words are used indiscriminately, but they do have different meanings.
Vaccination is introducing immunogens in to the body to stimulate the immune system to build antibodies to fight infections. It is the most efficient and widely used immunization method. Small pox, measles, tetanus and polio are some very popular and effective vaccines used throughout the world. The word “vaccination” comes from Latin “vacca” meaning cows, because the first ever vaccine was made from a virus affecting cows. Vaccination is important because it gives the body a chance to produce antibodies and hold a memory so that when the actual infection occurs, the defense will be so strong to protect the body from its dangerous consequences. Some vaccines are also given after contracting the disease.
Most vaccines are given as injections, but some like polio and cholera are given orally. Depending on the type of vaccination four main classes are identified. Inactive vaccines are when they contain the killed bacteria or virus where the immunogen is either a protein capsid of the virus or the bacterial cell wall. The others are either giving attenuated, live virus or bacteria, viral particles, or giving an isolated compound like bacterial toxins.
Immunization is the process which increases immunity of the body towards pathogens. Immunization can be natural or artificial. Vaccination is one artificial immunization method. The three main elements, which do this, are antibodies, T cells, and B cells. Natural immunization is the process where a person gets an infection first and then by producing antibodies and other substances fight and survives the infection. Artificial immunization like vaccination is important because many pathogens are very harmful that the natural process is not intense and fast enough to survive the infections. Immunization can be either active or passive.
Active immunization is the introduction of an immunogenic substance to the body where the body produces antibodies to fight the infection. Active immunization can occur naturally when an infection happens or artificially when vaccines are given. Passive immunization is to introduce already prepared antibodies or other immune-elements directly to the body. Passive immunization occurs naturally when antibodies are passed from mother to the fetus or artificially when antibodies are given as injections.
What is the difference between Vaccination and Immunization?
• Vaccination is a type of immunization, but immunization is not necessarily vaccination alone.
• Vaccination is an artificial process, whereas immunization can be natural or artificial.