vaccine(redirected from virus-vectored vaccine)
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vaccination, means of producing immunity against pathogens, such as viruses and bacteria, by the introduction of an killed or weakened microorganism, a harmless piece of a microorganism, or the like to stimulate the body to produce antibodies against more dangerous forms. Vaccination was used in ancient times in China, India, and Persia, and was introduced in the West in 1796 by Edward Jenner. Jenner demonstrated that rubbing or scraping the cowpox virus (the term vaccine comes from the Latin vacca, cow) into the skin produced only a local lesion but was sufficient to stimulate the production of antibodies that would defend the body against the more virulent smallpox. Modern vaccines may use an inactivated or killed microbe; a weakened or altered (attenuated) live microbe; an inactivated toxin (toxoid); a harmless component (subunit) of a microbe, such as a protein or sugar, which may be combined with a substance (adjuvant) or protein that provokes a stronger immune response, or a gene inserted into another virus or cell to produce a protein; or messenger RNA (mRNA), which provides the instructions for producing a protein.
Vaccination has eradicated smallpox worldwide and prevents such diseases as cholera, rabies, and typhoid fever. Vaccines work with the immune system's ability to recognize and destroy foreign proteins (antigens) that it determines are “nonself.” Scientists are using this same principle to help the body recognize antigens peculiar to cancer cells. It is also applied in an experimental04/96 birth control vaccine that tricks the immune system into believing that human chorionic gonadotropin (HCG), a hormone secreted by a developing fertilized egg, is foreign, thus inactivating it and inducing menstruation even if fertilization has occurred. Vaccines are also used to control animal pests by conferring temporary infertility.
Vaccination programs have been notably successful in the United States. For example, in 1998 the Centers for Disease Control and Prevention reported only one case of poliomyelitis, one of diphtheria, 34 of tetanus, and 89 of measles. Despite the availability of vaccines, many thousands of people in the United States still die each year from vaccine-preventable diseases such as hepatitis and influenza.
Immunization against 17 diseases is recommended for young children and adolescents: hepatitis B (HepB); rotavirus; diphtheria, tetanus (lockjaw), and pertussis (whooping cough), given together as DTaP (formerly DTP) and, for older children, Tdap; Haemophilus influenzae b (Hib); poliomyelitis (IPV); pneumococcal infections, including pneumonia, meningitis, and bacteremia (PCV and PPV); measles, mumps, and rubella, given together as MMR; chickenpox (Var); hepatitis A (HepA); influenza; Neisseria meningitidis (meningococcal meningitis; MCV4, MPSV4); and human papillomavirus (HPV). Vaccination for shingles (herpes zoster) is recommended for persons aged 50 yearsor older, and annual vaccination for influenza is recommended for everyone six months or older. Researchers are working to develop combination vaccines that would simplify vaccine administration. Immunization against diseases such as yellow fever may be necessary before traveling to some countries. In 2002 the U.S. government decided to reinstitute smallpox vaccination for many military, health-care, and emergency personnel because of concern about a possible bioterror attack using smallpox.
See also inoculation.
See study by A. Allen (2007).
a preparation obtained from microorganisms (bacteria, rickettsias, viruses) or products of their activity and used for active immunization of human beings and animals for prophylactic and therapeutic purposes. Vaccine was first used in 1796 by the English physician E. Jenner, who inoculated persons with cowpox, or vaccinia (hence the name “vaccine”) to protect them against smallpox.
Live, killed, and chemical vaccines and toxoids are distinguished.
Live vaccines are made from specially attenuated cultures of microorganisms deprived of their capacity to cause disease but remaining capable of reproducing in the body and causing immunity. The first to create live vaccines against anthrax (1881) and rabies (1885) was the French microbiologist L. Pasteur. The live tuberculosis vaccine (BCG) proposed in 1926 by the French scientists A. Calmette and C. Guérin won universal recognition; it greatly reduced the tuberculosis rate. Many live vaccines were created by Soviet scientists: for example, typhus vaccine (P. F. Zdrodovskii, 1957-59), influenza vaccine (A. A. Smorodintsev, V. D. Solov’ev, and V. M. Zhdanov, 1960), brucellosis vaccine (P. A. Vershilova, 1947-51), and smallpox vaccine (M. A. Morozov, 1941-60). Vaccines are the only effective inoculative preparations for certain diseases (rabies, smallpox, plague, tularemia). Live vaccines generally produce long-lasting immunity.
Killed vaccines are made from microorganisms killed by physical methods (heating) or chemical methods (phenol, formaldehyde, acetone). Killed vaccines are used to prevent only those diseases for which live vaccines are not available (typhoid, paratyphoid B, whooping cough, cholera, tick-borne encephalitis). They provide less protection than live vaccines. Hence immunity develops only after a course of immunization (vaccination) consisting of several inoculations.
Chemical vaccines are substances isolated from bacterial cells by various chemical methods and containing the main elements that cause immunity. Chemical vaccines against intestinal infections were first employed in 1941 as part of the NIISI polyvalent vaccine proposed by the Soviet scientists N. I. Aleksandrov and N. E. Gefen. Chemical vaccines are used to provide protection against paratyphoid B, typhoid, and rickettsial diseases.
The development of immunity following the injection of toxoids results from the appearance in the blood of antibodies that neutralize the effect of a particular toxin. Toxoids were obtained for the first time during the years 1923-26 by the French scientist G. Ramon. Toxoids are used to prevent diphtheria, tetanus, botulism, gas gangrene, and staphylococcal infections.
Vaccines can be made from the causative agent of a single infection, so-called monovalent vaccines, or from a combination of two or more causative agents, polyvalent vaccines. The latter produce immunity to several infectious diseases.
There are various methods of administering vaccines. In the case of live vaccines, they are related to a certain extent to the routes by which the causative agents enter the body. Thus, poliomyelitis vaccine is administered orally; influenza vaccine intranasally; smallpox, anthrax, and tularemia vaccines epidermally; brucellosis vaccine intradermally; typhus vaccine subcutaneously. Killed vaccines and toxoids are injected subcutaneously or intramuscularly.
Live vaccine is used to treat rabies (vaccine therapy), the only method of protecting man from this fatal disease. Autovaccines are used to treat several chronic inflammatory diseases caused by staphylococci and streptococci.
In the USSR, vaccines are produced by scientific production institutions. The quality of the preparations is controlled by the L. A. Tarasevich State Control Institute for Biomedical Preparations in Moscow.
A. KH. KANCHURIN
Vaccines in veterinary medicine. The principles used in preparing and classifying vaccines for the treatment of animal diseases are the same as those for human diseases. The most widely used live vaccines in veterinary practice include anthrax vaccines—STI and GNKI; swine erysipelas vaccine —from the Konev strain and VR2; brucellosis vaccine— from strain 19; and vaccines against cholera, smallpox, and Newcastle disease. Killed vaccines are used to prevent and treat more than 20 infectious diseases of animals.
REFERENCESRamon, G. Sorok let issledovatel’skoi raboty. Moscow, 1962. (Translated from French.)
Vygodchikov, G. V. “Nauchnye osnovy vaktsinno-syvorotochnogo dela.” In Mnogotomnoe rukovodstvo po mikrobiologii, klinike i epidemiologii infektsionnykh boleznei, vol. 3. Moscow, 1964. Pages 485-506.
Kravchenko, A. T., R. A. Saltykov, and F. F. Rezepov. Prakticheskoe rukovodstvo po primeneniiu biologic he skikh preparatov. Moscow, 1968.
A. KH. KANCHURIN
and S. G. KOLESOV