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What is the causative agent of syphilis

The causative agent of syphilis (Treponema pallidum, Treponema pallidum) is a bacterium that is the cell wall and able for some time to persist in the environment. This microorganism belongs to the spirochetes, has the form of spirals with small curls. The number of whorls of 8 to 12. Shape and amount of curls this bacterium determined by smear microscopy.

Characteristics of the microorganism

How long can survive in the environment, the causative agent of syphilis? In contact with household items (often towel, bed linen) pale Treponema is maintained until the drying of the substrate, in which she was. This is usually detachable from erosions and ulcers, saliva, semen, etc. for About 15 minutes survives at a temperature of 55 degrees, with the higher death of the microorganism occurs much faster. Boiling can kill the bacteria within a few seconds.

Almost not colored the usual dyes used in Microbiology, for visulization this species of spirochaetes are mainly used contrast methods of microscopy – light to dark. This is because the shell is the causative agent of syphilis is sufficiently thin, get damaged quickly under the influence of alcohol (it is used as a dye fixing). Also spirochetes can be silver, then the color under the microscope becomes a red-black.

Detrimental to Treponema pallidum are the following substances and environments:

  • arsenic and bismuth;
  • penicillin;
  • mercury;
  • acid and alkali;
  • light and UV;
  • solutions of disinfectants and antiseptics, alcohol, vinegar.

However, according to some studies, while conducting experiments on the stability of pale treponem in the environment were the results on preservation of microorganisms in adverse conditions when access of oxygen, poor environment, able to drying and when exposed to light. The term of preservation of the causative agent of syphilis in such conditions for about 3 years.

Growth on nutrient media and core antigens

Treponema pallidum is poorly cultivated on special nutrient media due to her moodiness. Chicken embryos and human cell culture are not suitable for the cultivation of this microorganism. Practically the only available method suitable for the isolation of culture, is the infection of laboratory rabbits and the development of these specific orchitis.

Another way is to obtain a culture enriched on a special production environments under a layer of paraffin oil. This method is currently used to obtain the necessary in laboratory diagnosis of antigens, which are all specific reactions for syphilis.

Antigenic structure of paleTreponema includes a set of lipoprotein, polysaccharide and lipid substances. Part of the antigens overlap with other spirochaetes, however, there are highly specific antigens. Treponema pallidum has not serogroup or serovar.

Экспресс тест на сифилис

In conclusion, I want to emphasize the possibility of the causative agent of syphilis change the antigenic structure and form of existence that may bring some difficulties in the treatment and verifizierung this disease.


  1. The order of Ministry of health of the Russian Federation dated 26.03.2001 № 87 "On improving the serological diagnosis of syphilis".
  2. The sustainability of the cultural pale treponem (CBT) to change optimal culture conditions. Kaziev Azret, Joseevich. Bulletin of the Russian University of friendship of peoples. Series: Medicine. No. 4, 2010.
  3. Microbiology. A. A. Vorobyov, A. S. Bykov, E. P. Pashkov, A. M. Rybakov.