The abbreviation HIV refers to the human immunodeficiency virus, which is the causative agent of AIDS. The pathogen affects the body's defense system, as a result of which it cannot function normally and prevent the development of various ailments. Currently, it is impossible to get rid of the causative agent of HIV, all methods of treatment are aimed only at slowing down the reproduction of the virus. This allows patients to significantly extend their lives.
Key Features
The causative agent of HIV infection was discovered at the end of the twentieth century (in 1983). The virus was discovered simultaneously by two scientists from the United States and France. 2 years before the discovery of the pathogen in America, the acquired immunodeficiency syndrome, known as AIDS, was first described. Currently, it has been found that the causative agent of HIV has two types. The first is common in European countries and the USA, the second is in West Africa.
Information regardingthe origin of the pathogen is extremely small. To date, the main hypothesis is that which states that the causative agent of HIV infection was formed as a result of a mutation of monkey viruses. It originated in Africa, where it became widespread. For many years, he did not go beyond the borders of the country, affecting an increasing number of indigenous people. Gradually, the development of African territories took place, as a result of which the indicator of migration flows increased and contacts were established with some states. The natural consequence was the wide spread of the pathogen.
Main characteristics of the causative agent of HIV infection:
- Related to retroviruses. This family is characterized by the presence of a genetic apparatus represented by ribonucleic acids.
- The virus is a spherical particle. Its dimensions can vary from 80 nm to 100 nm.
- The causative agent of HIV consists of a protein shell, nucleic acid and a special enzyme. The latter contributes to the transformation of the RNA of the virus into pathogenic DNA. After that, it is introduced into the human macromolecule responsible for the implementation of the genetic program.
The disease can proceed in different ways. Sometimes it develops rapidly, more often it stretches over several years. Maintenance therapy can increase the patient's life expectancy. The lack of treatment inevitably leads to death in a shorter time.
Sustainability
The causative agent of HIV infection isa pathogen that can only develop in the cells of other organisms. The virus exhibits an extremely low degree of resistance in the external environment. It can reproduce only in the human body.
The pathogen is resistant to low temperatures, its vital activity does not stop even when frozen. Neither ultraviolet nor ionizing radiation has any effect on it. In this case, the causative agent of HIV infection is a pathogenic microorganism that instantly dies when boiled. If the temperature is slightly lower, its vital activity stops after about half an hour.
In addition, the pathogen quickly dies under the influence of alcohol 70%, acetone solution, hydrogen peroxide 5%, ether, chloramine. In dried form, the viability of the virus lasts up to 6 days. In a solution of heroin, all the properties of the pathogen remain for about 3 weeks.
Life cycle phases
He is quite complex. The life cycle of the HIV pathogen consists of several stages:
- Cells circulating in human blood are T-lymphocytes. On their surface are receptor molecules. The virus binds to them and penetrates into T-lymphocytes, while the pathogen sheds its protein coat.
- The DNA copy is synthesized. This process is carried out due to the presence of reverse transcriptase enzyme in the virus.
- The formed copy of DNA is introduced into the cell nucleus. There is the formation of a ring structure. After that, it is integrated into the carrier macromolecule.
- A copy is stored in human DNAsome years. In this case, the infected may not feel any alarming signs. The presence of a copy of DNA can be detected in a person's blood randomly, for example, during a preventive examination.
- When a secondary infection enters the body, the process of viral RNA synthesis starts.
- The latter also produces disease-causing proteins.
- New pathogenic particles begin to form from the newly synthesized substances. They then exit the cage, which usually dies.
In the above phases of the life cycle is the mechanism of transmission of the HIV pathogen.
Impact on the immune system
The body's defenses are designed to neutralize and destroy antigens coming from outside. Foreign elements include all viruses, bacteria, fungi, protozoa, pollen, yeast, and even donated blood.
The immune system is represented by cells and organs that are located throughout the body. T-lymphocytes are responsible for the formation of the reaction. It is they who initially determine that the causative agent of the disease (HIV infection) is an antigen. After recognizing a foreign element, T-lymphocytes start the synthesis of a number of substances that accelerate the process of maturation of new protective cells. After that, the production of antibodies occurs, the main task of which is the destruction of pathogenic microorganisms.
But the virus is able to quickly penetrate into T-lymphocytes, due to which the body's defenses are weakened. Developingimmunodeficiency. Often HIV is present in the body, but the infected person is not even aware of it. The inactive period is from 1 to 5 years. At the same time, a small amount of antibodies circulate in the blood, which have managed to be developed by the immune system. It is their presence in the liquid connective tissue that is the basis for the diagnosis.
As soon as the virus enters the blood, a person is considered to be its carrier, that is, it can infect others. In this case, the only symptom, as a rule, is an increase in some lymph nodes.
Over time, the virus becomes activated, it begins to multiply very quickly and destroy T-lymphocytes. In other words, one of the main links of the defense system is being destroyed. At the same time, when various pathogens enter it, the body waits for a signal from T-lymphocytes about the beginning of the formation of an immune response, but it does not arrive. Thus, a person becomes defenseless even against banal infectious diseases that do not pose a danger to he althy people.
The progression of immunodeficiency is accompanied by the formation of tumors. Over time, the brain and nervous system are involved in the pathological process.
Transmission routes
The source of infection is always a person (both suffering from AIDS for many years, and a carrier). According to the main theory of the origin of the pathogen, the reservoir of HIV of the first type is wild chimpanzees, the second - African monkeys. At the same time, the rest of the animals to infectionimmune.
The following types of human biological material pose the main epidemiological danger:
- blood;
- vaginal secret;
- cum;
- menstrual flow.
The least dangerous are: saliva, breast milk, cerebrospinal fluid, tear secretion.
Main routes of HIV transmission:
- Natural (during sexual intercourse, from mother to child during fetal development or during the delivery process). The risk of infection after a single sexual intercourse is very small. It increases significantly with regular sexual contact with the carrier. From mother to child, the virus is transmitted through defects formed in the placental barrier, when the baby comes into contact with blood during delivery or with breast milk. According to statistics, the incidence rate among newborns is approximately 30%.
- Artificial (with parenteral administration of drugs, transfusions, medical procedures that are traumatic, etc.). One of the main routes of transmission of the causative agent of HIV infection is injection with needles that are contaminated with the blood of a person suffering from AIDS or a carrier of the virus. Also, infection often occurs during medical procedures in violation of sterility standards: tattooing, piercing, dental procedures.
The causative agent of the disease (HIV) is not transmitted through household contact.
There have been cases whena person was found to be immune to the virus. Scientists believe that this is due to the presence of specific immunoglobulins present on the mucous membrane of the genital organs.
Symptoms
The development of immunodeficiency is slow. During HIV infection, it is customary to distinguish several stages:
- Incubation. Its duration ranges from 3 weeks to several months. The stage is characterized by intensive reproduction of the virus, while there is still no immune response from the body.
- Primary manifestations. The formation of an immune response is accompanied by an intensive production of antibodies. At this stage, warning signs may not appear. But most infected people experience the following symptoms: fever, rashes on the skin and mucous membranes, swollen lymph nodes, diarrhea, pharyngitis. In some patients, the acute stage is accompanied by the addition of secondary infections (tonsillitis, fungal pathologies, pneumonia, herpes, etc.). In this case, signs of emerging ailments join. The duration of the stage of primary manifestations is about three weeks.
- Latent. It is characterized by the progression of immunodeficiency. In this case, the only symptom is only an increase in lymph nodes. The duration of the stage varies from about 2 to 20 years.
- Stage of secondary diseases. The patient's body weight decreases, working capacity decreases, well-being worsens. In severe cases, secondary infections become generalized.
- Terminalstage. At this stage, the violations caused by the development of secondary diseases are irreversible. In this case, any methods of treatment are ineffective. This stage ends in death.
HIV infection is characterized by a diverse course, that is, some stages may be completely absent. The duration of the development of the disease ranges from several months to many years.
Diagnosis
The causative agent of HIV infection is a retrovirus. For their detection, the ELISA or PCR method is most often used. Sometimes the doctor additionally prescribes a laboratory test using the method of immune blotting. During the diagnostic process, the specialist has the ability to identify antibodies to HIV, which is the basis for making an accurate diagnosis.
Treatment
All conservative therapies are aimed at slowing the progression of the disease and preventing the development of secondary infections.
Typically, a treatment regimen for people with HIV includes the following:
- Taking antiretroviral drugs. The active substances of the drugs help to reduce the rate of reproduction of pathogens. These drugs include the following: Zidovudine, Zalcitabine, Abacavir, Nevirapine, Ritonavir, Nelfinavir, etc.
- Taking vitamins and dietary supplements.
- Physiotherapy.
- Strict adherence to the regime.
- Diet.
- Psychological help.
It is important to understand that the expediency of taking certaindrugs are evaluated only by a doctor. Immunostimulants for HIV infection are not prescribed. This is due to the fact that such drugs contribute to the progression of the disease.
It is important to treat secondary pathologies in a timely manner. If the patient suffers from drug addiction, he must be placed in an appropriate inpatient facility.
Forecast and prevention
It is impossible to get rid of HIV. In this regard, the determination and psychological state of the patient play a decisive role. Previously, patients lived, on average, 11 years after infection. At present, a large number of modern drugs have been created, and an effective maintenance therapy regimen has been developed. If you strictly follow the doctor's instructions, the life span increases significantly and can be several decades.
The main preventive measures are: avoidance of casual sexual contacts, timely treatment of genital infections, visiting only reputable medical institutions, regular check-ups with a doctor.
Currently, special attention is paid to gender illiteracy. In order to remedy the situation, many schools and universities include special courses in the curriculum.
In conclusion
HIV is the causative agent of AIDS, but the infection can take years to develop. It is introduced into T-lymphocytes upon penetration into the body, due to which the functioning of the immune system is disrupted. As a result, a person becomes helpless even before a common cold.
When an illness is detected, the patient must follow the rules of maintenance therapy for life, otherwise the onset of death will accelerate.
The main measure of prevention is the exclusion of casual sexual relationships. In addition, it is not recommended to visit dubious medical facilities for traumatic procedures.
