Immunity, Vaccines, and Infectious Diseases
1. The term immunity is derived from the Latin open pal immune, it means to be free of charge, or be invulnerable to a particular infectious disease.
Immunity can be of two types: congenital or acquired.
Congenital or natural immunity, is one that is inherited, which develops the body itself at the individual level, racial or specific and is determined by the specific characteristics of the individual’s constitution, race or species.
Acquired immunity is acquired during life and can be further:
– Natural: Lifetime is acquired either a passive mode, ie during embryonic development and infant to receive maternal antibodies or an active mode, after passing an infectious disease.
– Artificial artificial techniques are acquired by either a passive mode, by the administration of serum, or in an active way, by the administration of vaccines.
“Active immunity is acquired after having produced an immune response in which the individual acquires immunological memory, ie ability to rapidly generate a large number of specific antibodies in subsequent contacts with antigens. Only the memory and generates active immunity lasts. “Passive immunity is achieved when the antibodies that confer immunity has produced the other body. Its action is short-lived, because passively immunized individual does not generate new antibodies.
2. Vaccines are antigens from one or more pathogens whose administration stimulates the formation of antibodies, which implies that the organism inoculated artificially acquired active immunity against the organism. Vaccination is always made as disease prevention, as a prophylactic. Serum is blood plasma from which cellular elements have been removed, but containing molecules such as antibodies and proteins characteristic of the animal. When immunity is achieved by fluid therapy talking about artificial passive immunity.
Traditionally has been to treat the patient suffering from a disease with blood serum from an animal that was previously inoculated microorganisms of the disease (vaccination), as introduced into the patient already formed antibodies against the disease. Normally horse serum was used, but now, thanks to genetic engineering techniques, can be manufactured sera from microorganisms whose genome has incorporated the genetic information necessary to synthesize, in the absence of pathogen-specific antibodies against him . The fluid therapy is used for curative purposes in individuals and patients, resulting in a limited passive immunity.
3. A toxin is a proteinaceous substance that causes the functional specificity of some bacteria.
The toxins are characterized by their ability to cause damage to the host, but in reality the causes of bacterial diseases. There are two types of toxins: – The exotoxins, proteinaceous, thermolabile and secreted externally by Gram-positive bacteria, which possess high toxicity. – Endotoxins, structural components of Gram-negative bacteria and toxigenic whose capacity is much lower than that of endotoxin. Tetanus is an illness produced by Clostridium tetani that produces an exotoxin.
1. The degree of pathogenicity of a microorganism known as virulence and quantifiable. Pathogen is a microorganism that is capable of producing a disease pathogenicity refers to the ability of parasites to penetrate the host and anatomical and physiological changes occur as the disease. A toxin is a proteinaceous substance that causes the functional specificity of some bacteria. The toxins are characterized by their ability to cause damage to the host, but in reality the causes of bacterial diseases. There are two types of toxins:
“The exotoxins, proteinaceous, thermolabile and secreted externally by Gram-positive bacteria, which possess high toxicity.
-Endotoxins, structural components of Gram-negative bacteria and toxigenic whose capacity is much lower than that of endotoxin.
2.
HIV belongs to the family of retroviruses. These viruses are characterized by carrying genetic information in an RNA molecule to be copied into DNA during its replication cycle, through the action of an enzyme of the virus itself, or retrotrancriptasa reverse transcriptase.
The cycle begins when the retrovirus HIV interacts with a glucoproteínade host cell membrane. This interaction causes the membrane fusion of virus and cell with the consequent entry of retrovirus into the cell. After the loss of the coat protein is initiated reverse transcription of viral RNA by reverse transcriptase, resulting in a double-stranded DNA. An enzyme called integrase induces the integration of viral DNA into the host cell chromosome. The next step is the expression of viral DNA that leads to the formation of viral RNA, which translates to cause structural and enzymatic proteins of the virus. After the assembly of virions, they can be released to restart a new cycle by infecting new cells diana.El Retroviral HIV cycle is represented in the following scheme: 
3. The AIDS virus infects T4 lymphocytes causing their destruction and thus turning off the immune response, both cellular and humoral. Eventually, the body can not produce an immune response either against or infected T4 cells against the virus itself, or even against other opportunistic invading organisms or malignant cells that may be present and develop. As the system becomes weaker, the patient is more vulnerable to other diseases, which include pneumonia caused by Pneumocystis carinii, Kaposi sarcoma and other pathological conditions cánceres.Las immunodeficiencies are produced as a result of the absence, or failure, the function of one or more elements of the immune system. Given the origin of the baby, were distinguished: primary or congenital immunodeficiency, and secondary immunodeficiency or secondary or acquired immunodeficiencies adquirida.Las are those acquired after birth, and are due to extrinsic or environmental factors, such as most the drugs used in cancer chemotherapy, irradiation, malnutrition or infections. Among the secondary immune deficiencies may be cited that produced by HIV, which causes AIDS.