Immunity is the body's immunity and resistance to various infectious agents and foreign substances.Immunity provides a human barrier properties.There are two types of immunity: hereditary and acquired immunity.
Under hereditary immune person understands genetically assigned to a certain biological species immunity and, as the name implies, it is inherited.It is thanks to this kind of immunity a person can not get sick, for example, canine distemper.Ensure the functioning of the body's innate immunity performed a variety of cellular and non-cellular factors.For example, the skin and mucous membranes are the most effective barrier to microbes.Protecting the body is carried out as sweat, greasy, salivary glands, more precisely, they emit substances detrimental to the majority of pathogenic bacteria.In the normal intestinal microflora contains microorganisms that are natural enemies of a large number of pathogens.Infection control is carried out in the digestive tract by gastric juice(hydrochloric acid), enzymes and bile.
body has a very strong natural protection.But this protection has enemies, represented by micro-organisms, alien molecules and cells.They are very volatile, and in the course of their cultivation, they can be more aggressive and can break through the first flank of the defense.Moreover, all that violated the integrity of the barriers or normal secretion of the body, lowers the natural immunity.As these factors may make stress or hypothermia, medications, or a lack of vitamins, surgery or hormonal imbalance.And in all these cases, microorganisms can penetrate into the body more easily.If the infection is passed a natural barrier and got into the bloodstream of the body, it may be several variants of the antigen-body relationship, one of which - an infectious disease.And if you start to develop an infectious disease, it starts another link that is called acquired immunity rights.This link and continues to further the fight against infection.
as the main characteristics of the acquired immunity serves to develop specific antibodies against a particular antigen.Formation of adaptive immunity occurs during life.It is unique like a fingerprint and is a kind of "medical history of man", he is prone to changes depending on what diseases a person had been transferred to him and which are peculiar habits.Acquired immunity can be acquired natural and artificial, active or passive.If the appearance of immunity due to an illness, it is natural.Once the body has been directed attack pathogens he begins to make antibodies.Sometimes their body is protected from re-infection for several weeks and months.And sometimes it is protected for many years or a lifetime.
After the discovery of vaccination people become vaccinated against various diseases and the immune system, which was acquired after vaccination is called artificial.If a person entered the weakened pathogens that cause the body's immune response, it is artificially acquired active immunity.When introduced into the body ready antibodies, they entail the occurrence of passive immunity.Passive immunity of the body has an important advantage: it is able to protect the person who had contact with the patient as soon as possible.But there are drawbacks: passive immunity is short-lived and weaker than the active.
newborn baby newborn baby a passive immunity.He gets through the placenta antibodies directed against pathogens of the diseases that the mother was ill or that she was immunized.The weakening of the passive transplacental immunity begins to 3-6 months.Completely it is extinguished at the end of the first year of baby's life.But vskarmlivaya-feeding may increase its immunity.