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A vaccine is composed by forming attenuated or killed pathogens, fragments thereof or a produced antibody. After the vaccine, the body develops protection against the specific disease, so if enough people are vaccinated against the disease, the vaccine will reach a certain level and develop a herd immunity against it.
The first artificial immunization in the world was the vaccine of English surgeon Edward Jenner. He saw that dairy women and dairy farmers infected with smallpox did not catch human smallpox, which happened in 1796. Jenner used the term vaccine, meaning “vaccantion,” the cow’s Latin name is “Vacca,” hence it. However, there was no explanation as to why his method worked at that time, of course no one had seen the submicroscopic Podxvirus varioale virus. This type of vaccination was successful, but only gradually in the world since the last smallpox outbreak occurred in 1972 in Yugoslavia, where a teacher visiting Iraq after a pilgrimage to Mecca, that teacher was infected with the virus.
Smallpox was used to immunize in India or China in the early second century BC. In 1718, the Turks were similarly exposed to the secretions of mild patients to be immune, Mary Wortley Montagu reported. He himself used the same method on his children.
After the yellow fever epidemic in Philadelphia in 1793, the Philadelphia Lazaretto Quaratine Station opened in 1799. All ships that arrived in the city had to dock here and undergo detailed inspection, and infected passengers had to be quarantined. It was the first quarantine in the modern world history.
In 1820, the number of deaths caused by smallpox halved: from 18,447 to 7,858, then in 1855 Massachusetts became the first state to make vaccination compulsory.
Added vaccines were developed in the 20th century against diphtheria, measles, mumps, and rubella, among others. Most of the developments were led by Maurice Hillerman.
Types of immunization can be active, which have lived, attenuated pathogens, or inactivated, killed pathogens, or other specially administered antigens.
The body responds to the vaccine with an immune response. White blood cells (T and B lymphocytes) as well as macrophages take part in the cellular process. Interestingly, immunological memory develops during the process, so this means that the immune response will be faster and greater when met with a given antigen.
The passive immunization is an antibody already ready against a certain pathogen. Such protection can be given to those whose immune system is unable to respond to infection including a weakened immune system.
Attenuated vaccine that has live but attenuated pathogens, do not cause disease when they enter the body but multiply, thus mimicking their immunological effects by mimicking a process like a natural infection.
The third type may be passive immunization with an antibody, which is specific for the administration of IgG class antibodies. These vaccines are prepared from the blood serum of individuals with antibodies, and antibodies can be used for passive immunization. However, the method starts to work quickly, but supplies short-term protection because natural antibodies are broken down, and if there are no B cells to produce more antibodies, they simply disappear. The effect is transient with a mean half-life of 21 days.