Testing for human immunodeficiency virus indicates whether the patient is infected. When conducting a study in the blood serum, they look for antibodies to HIV. With the penetration of the retrovirus into the body by the immune system, antibodies and antigen proteins begin to be produced. For healthy, not infected people, the presence of such antibodies in the blood serum is uncharacteristic. However, they can appear in newborn babies whose mother is infected with the immunodeficiency virus. In such children, antibodies that can cross the hematoplacental barrier from mother to child may persist until the age of one and a half years.
Disease characteristics
HIV infection is a pathological condition, which is a disease whose causative agent develops in the human body for a long time. At the moment, there are no effective means of combating the disease. In addition to the inability to cure the disease after infection, at the moment you can only prevent infection by conducting preventive measures. After the pathogen enters the bloodstream, the rapid destruction of immune defense cells - leukocytes - begins. Infection is characterized by the rapid spread and decrease in the body's defense against external influences. Microorganisms are able to penetrate into the body cavity through cell membranes and empty spaces of intercellular fluid, interfering with the performance of its functions. As a result of this, the human body almost completely loses its barrier function over time, which completely eliminates the possibility of victory over an infectious disease. The process of infection and a decrease in immunity is very long. The virus is able to destroy the human body for more than ten years. At the same time, antibodies to HIV groups 1 and 2 appear in his blood.
Transmission ways
The source of infection is a person. However, higher primates may also be carriers of the disease. A particularly high number of microorganisms lives in moist environments: blood, semen and serous secretion of the uterus. Therefore, the transmission of the disease is diverse.
The human immunodeficiency virus is most often transmitted sexually, especially if personal protective equipment is not used. In this case, the microorganism penetrates into the body of a healthy person through cracks and scratches in the mucous membranes of the genitals. In addition to AIDS, unprotected sex leads to various STDs (sexually transmitted diseases).
Infection is possible with direct contact with the patient’s blood. So, the transfer is possible using personal hygiene products: razors and scissors, medical instruments, syringes. In addition, transmission can occur when injecting drugs into a vein or in beauty salons when using non-sterile instruments.
Possible transmission from a mother with an HIV-infected child to a child. Moreover, during gestation, transmission is unlikely due to the hematoplacental barrier. Infection most often occurs at the time of birth.
Disease development
The course of the disease is long. Depending on the number of microorganisms in the human body and the affected T-lymphocytes, signs may not be detected for a long period. Even if the immune system releases antibodies to HIV, then the symptoms of the disease most often also do not appear. In fact, the development of the disease is divided into such periods.
- The incubation period is a period of time that begins with the time of infection and ends when antibodies and antigens against HIV appear in the blood serum.
- The second period is characterized by primary symptoms. It begins after the appearance of HIV antigens and is characterized by a very high rate of virus reproduction in serum. The number of particles responding to infection is greatly increasing. During this period, a pathological condition can be diagnosed. In most patients, the symptoms of the disease do not appear. However, hyperthermia, an increase in the size of the lymph nodes, severe pain in different parts of the head, and muscle weakness may occur. Possible pain during movement and general malaise.
- The third period is characterized by the absence of symptoms. The course is very long. During this period, huge damage to the body is gradually caused, the activity of T-group lymphocytes decreases. The number of pathogenic microorganisms in the body cavities and blood serum increases significantly. The period is also characterized by the appearance of manifestations of concomitant sexually transmitted diseases. Neoplasms of various nature may occur.
- The last stage of the disease is acquired immunodeficiency syndrome. This period is accompanied by a significant number of secondary sexually transmitted diseases, the diagnosis of which is not difficult. Over time, the remaining systems of the body begin to be affected: respiratory, nervous, humoral. This is fatal.
What if antibodies are detected?
After the diagnosis, when detecting antibodies and antigens to the human immunodeficiency virus, it is necessary to monitor the general state of human health. It is necessary to regularly carry out diagnostic measures aimed at establishing concomitant diseases. At the moment, pharmacologists have not found drugs against the immunodeficiency virus, therefore it is necessary to maintain the state of the human immune system at a sufficient level. In this case, it is necessary to be examined for diseases that are sexually transmitted, the manifestations of which are very clearly expressed against the background of the body's immune depression.
Indications for diagnostic measures
Screening for immunodeficiency virus infection can be done in several different ways. However, to clarify the diagnosis, you may need to go through several studies in stages. Usually the first study is an enzyme-linked immunosorbent assay for serum content. A study is underway to detect exoenzymes that are secreted by the virus. In case of an uncertain result or in case of inaccuracy after receiving the results, the patient may be referred for additional examination. HIV antibody tests are required in the following situations:
- During pregnancy planning.
- During pregnancy.
- After sexual contact with a little-known partner.
- When the patient has an unreasonable fever.
- If the weight of the subject fell sharply.
- With inflammatory processes of the lymph nodes in several areas of the body.
- In preparation for surgery.
Regarding children or newborns whose mother is infected, the diagnosis that is carried out for them is not accurate. The absence of antibodies in children cannot accurately prove the absence of infection. Therefore, you will need to regularly conduct diagnostic measures during the growth period.
AIDS indicator diseases
Given the reduced immune response to other diseases by the World Health Organization, some diseases have been identified as AIDS marker or AIDS indicator. Diseases are divided into two groups. The first includes pathologies that appear only in severe immunodeficiency (the level of T-lymphocytes in the blood is not higher than 200). The second group includes diseases that can occur without high immunodeficiency syndrome.
The first group includes:
- Fungal diseases of internal organs: candidiasis, cryptococcosis.
- Infections caused by the herpes simplex virus, with the appearance of ulcers that do not heal for a long time.
- Kaposi's sarcoma in adults and young patients
- Lymphoma of the brain in patients under 60 years of age.
- Toxoplasmosis GM in children.
- Pneumocystis pneumonia.
The second group includes:
- Infections provoked by bacterial microbes in children under 13 years of age with their frequent appearance.
- Coccidiosis associated with mycosis.
- Mycoses.
- Salmonella septicemia.
Antibodies to HIV 1 and HIV 2
This phenomenon may occur after infection. When HIV antibodies are detected, what does it mean? Usually, antigenic proteins appear after infection. In a normal state, protein antigens in serum are not detected. Determination of antibodies to HIV is the main way to diagnose a disease. For its use, an enzyme-linked immunosorbent assay, which is sensitive to almost all proteins. The search for indicator proteins for HIV occurs on the 4th week after the probable infection in most recipients. In addition, the presence of antibodies to HIV can be detected in 10% of patients 6 months after infection. At the last stage of the disease, the amount of antibodies in the blood is almost zero.
Result
A blood test for antibodies to HIV is carried out using qualitative reactions. Therefore, the result is defined as positive or negative. With a negative result, it is believed that antibodies to the immunodeficiency virus in the patient's blood are absent. This test result for antibodies to the HIV virus is issued to the hands immediately after receipt.
If you get a positive result, you need to conduct additional examinations. On the same material, an additional two analyzes are carried out. This happens to eliminate false results.
Next steps
If the result is positive, it will be necessary to send patient data and blood samples to the regional health center. A positive result is confirmed there or an unreliable one is clarified. Under these circumstances, the response to the examination is issued by the regional center of the acquired immunodeficiency syndrome.
Additional examinations
If antibodies to HIV are not detected during the enzyme-linked immunosorbent assay, additional tests for a specific category of antigens may be prescribed. Screening for anti-HIV proteins includes:
- Diagnosis on p24.
- Diagnosis by polymerase reaction.
P24 analysis
A protein is a wall protein of the genetic material of a virus. Its presence in the blood is evidence of the onset of viral division. May appear approximately 2 weeks after infection. Testing by enzyme immunoassay will give a result in the period from a month to two. After 8 weeks, the antigen completely disappears from the blood. The second formation of p24 antigen occurs in the last stages of the development of the disease, before the formation of human immunodeficiency syndrome.
Polymerase Assay
The reaction is carried out to clarify inaccurate results of preliminary examinations or for early detection of infection. In addition, it can be carried out to detect the current stage of the disease. The technique allows you to find the gene material of the virus in the blood serum 2 weeks after infection. In this case, you can get a quality result:
- A positive examination indicates the presence of ribonucleic acid specific for the human immunodeficiency virus in the blood.
- A negative result indicates the absence of gene material in the serum of the recipient.
Thus, it is realistic to check for the presence of infection in the patient. In addition to a qualitative reaction, the detection of antibodies to HIV is carried out using quantitative. This is used to determine the number of T-lymphocytes in the blood, then a forecast can be made regarding the further development of the disease and the patient's condition. A decrease in the number of cells is directly related to an increase in the number of pathogenic microorganisms.