Diagnostic drugs are used for the following purposes:
1) to determine with the help of specific immune sera the type or type of microbe isolated from a patient, a carrier or from objects of the external environment;
2) for the detection of antibodies in the serum of patients or convalescents with the help of diagnosticums;
3) to identify with the help of allergens the restructuring of the body that occurs in some infectious diseases.
All diagnostic drugs are antigens or antibodies.
General information on diagnostics
Diagnosticums are suspensions of killed microbes, most often in a physiological solution, used as antigens for serological reactions.
The advantage of diagnosticums over living culture is the stability of their agglutinable properties, standardization, safety and ease of handling. The use of diagnostic kits makes it possible to widely apply serological methods in the practice of mass work. Of particular importance are diagnostics in cases when working with live bacteria or viruses is dangerous due to their high infectivity (for example, sbrucella, tularemia bacteria, tick-borne and Japanese encephalitis viruses, etc.).
Diagnosticums used to recognize infectious diseases are divided into bacterial, rickettsial and viral. With their help in the serum of patients, it is possible to determine the presence of antibodies in relation to a certain type of pathogen microbe.
More subtle differences in antibodies in the visible serum are established using specific monodiagnostics. So, in case of typhoid fever, to determine group O-antibodies and species H-antibodies, the corresponding O- and H-diagnostics are used from the culture of typhoid bacteria 0-901 or paratyphoid bacteria No. 2, which have a common O-antigen by typhoid bacteria; H-diagnosticum is a suspension of bacteria with pronounced mobility.