The human body is characterized by a characteristic feature, which consists in the struggle against external stimuli that somehow get inside the body. Such an irritant may be an infection or a vaccine, which the immunity will take as a potential threat. With this situation, there is such a process and such a phenomenon as seroconversion.
Definition of a concept
Seroconversion is a process and period that is characterized by the development of antibodies by the immune system to combat the potential threat that has entered the body from the outside. In most cases, this threat is the human immunodeficiency virus (HIV) or vaccines used to protect against varieties of viral hepatitis. Moreover, in the case of HIV, seroconversion is a sign of an infected organism, and in the case of vaccination, antibody production by immunity serves as a criterion for the effectiveness of the drug administered.
Seroconversion and HIV
The human immunodeficiency virus proceeds in several stages. First, a person is infected: through sexual contact, through the blood. The virus infects the first cells, and after a few hours they end up in the bloodstream. Through it, the disease later enters 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 febrile state: high body temperature, sweating, headaches and muscle pains, weakness. During seroconversion, the virus concentration reaches a maximum, which makes the patient a dangerous source of possible infection.
After the seroconversion stage, there are 3 periods: primary HIV infection, chronic infection, and after it the last stage occurs - AIDS. Separately, it is worth highlighting cases of late seroconversion. Usually, having become infected with HIV, the patient will find out 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 drug containing a weakened virus that infects a person in order to form immunity against a specific disease. A 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 development of antibodies to the antigen that has entered the body.
Before administering the vaccine, blood serum is taken from the patient for subsequent comparison with serum taken after vaccination - during the period of a possible immune response. In this case, seroconversion is a phenomenon established by titration of two serum samples using a series of serological reactions ( antigen reaction to antibodies that concentrate in blood serum). By titration, a quantitative increase in titer is determined, which is considered in the volume of two dilution steps (i.e. 1: 2, 1: 4, 1: 8, and so on). An increase in titer can be either 4 times or 16 times or more.
Without a seroconversion, it is impossible to determine how effective the vaccination was. Quite often, the method of determining seroconversion is used when a vaccine against hepatitis A and B, as well as from mononucleosis, is introduced into the patient's body.
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 during human infection and vaccination.
In some cases, an increase in antibody concentration in the body is associated with HIV infection. Moreover, the period of seroconversion itself usually occurs 2-3 months after the virus enters the bloodstream. However, the phenomenon of late seroconversion also occurs 20-12 months after infection.
The determination of seroconversion also helps in evaluating the effectiveness of the administered vaccine. An increase in the number of titers in the second blood serum compared with the first taken before vaccination helps physicians evaluate the body's response to the vaccine, and therefore its effectiveness.