Diagnostics are suspensions of dead germs that serve as antigens for serological tests and allergens for allergic diagnostic tests.
Diagnosticums are widely used in the diagnosis of typhoid fever , paratyphoid fever , dysentery, brucellosis , tularemia , rickettsiosis , and leptospirosis. They are also used for the formulation of RSK (reaction of complement fixation) in the serological diagnosis of leptospirosis. For the diagnosis of typhoid fever used the so-called O-diagnosticum (for the detection of group, O-antibodies) and H-diagnosticum (for the detection of specific, H-antibodies). For the formulation of the agglutination reaction, most diagnostic kits are preserved with 0.1–0.2% formalin solution. Diagnostics from rickettsia and leptospira canned with phenol. In the formulation of the opsoe-phage-cytic reaction, diagnostica from microbes killed by heat are used.
In virology, antigens for RSK and antigens for RTG (hemagglutination inhibition reaction) are used as diagnostic kits.
Viral diagnostics is processed to reduce anticomplementary properties - processing by physical (repeated freezing and thawing) and chemical (exposure to ether and chloroform ) methods. See also Serological studies .