The human body is distinguished by a characteristic feature, which consists in the struggle against external stimuli, somehow got inside the body. Such an irritant can be an infection or a vaccine, which the immune system will take for a potential threat. In this state of affairs, such a process and such a phenomenon as seroconversion takes place.
Definition of concept
Seroconversion is a process and period that is characterized by the production of antibodies by the immune system to fight a potential threat that has entered the body from outside. In most cases, this threat is the human immunodeficiency virus (HIV) or vaccines used to protect against types of viral hepatitis. Moreover, in the case of HIV, seroconversion is a sign of an infected organism, and in the case of vaccination, the production of antibodies by immunity serves as a criterion for the effectiveness of the administered drug.
Seroconversion and HIV
The human immunodeficiency virus occurs in several stages. First, a person becomes infected: through sexual contact, through the blood. The virus infects the first cells, and after a few hours they are in the bloodstream. Through him diseaselater goes to the lymph nodes.
The virus begins to multiply actively. When its concentration increases to a certain volume, the immune system begins to produce antibodies against it - this is seroconversion. This stage of the disease is characterized by a feverish state: high body temperature, sweating, headaches and muscle pain, weakness. During the period of seroconversion, the concentration of the virus reaches a maximum, which makes the patient a dangerous source of possible infection.
After the stage of seroconversion, there are 3 periods: primary HIV infection, chronic infection, and after it comes the last stage - AIDS. Separately, it is worth highlighting cases of late seroconversion. Usually, having become infected with HIV, the patient learns about it in 2-3 months (or even faster). However, in medical practice, from time to time there are cases when the disease manifests itself only after 10-12 months.
Seroconversion and vaccination
A vaccine is a preparation containing a weakened virus that infects a person in order to form immunity against a specific disease. The drug introduced into the body can be perceived by the immune system as a threat. In this case, the phenomenon of seroconversion occurs, which consists in the production of antibodies to the antigen that has entered the body.
Before the vaccine is administered, the patient's blood serum is taken for subsequent comparison with serum taken after vaccination - during the period of possible immuneresponse. In this case, seroconversion is a phenomenon established by titration of two serum samples using a series of serological tests (antigen reaction to antibodies concentrated in the blood serum). By titration, a quantitative increase in titer is determined, considered in terms of two dilution steps (ie 1:2, 1:4, 1:8, and so on). The titer increase can be either 4 times or 16 times or more.
Without determining seroconversion, it is impossible to determine how effective the vaccination was. Quite often, the method of determining seroconversion is used when vaccinating a patient against hepatitis A and B, as well as against mononucleosis.
General conclusion
Seroconversion is not only a phenomenon, but also a period characterized by an increase in antibodies produced by the immune system against a potential threat. Antibodies are produced against antigens that occur both when a person is infected and when a person is vaccinated.
In some cases, an increase in the concentration of antibodies in the body is associated with HIV infection. Moreover, the seroconversion period itself usually occurs 2-3 months after the virus enters the bloodstream. However, the phenomenon of late seroconversion occurs 20-12 months after infection.
Determination of seroconversion also helps in assessing the effectiveness of the administered vaccine. An increase in the number of titers in the second blood serum compared to the first, taken before vaccination, helps doctors evaluate the body's response to the vaccine, andhence its effectiveness.
