In recent years, the epidemic situation in diphtheria has deteriorated sharply. An essential point in assessing the dynamics of the epidemic process of diphtheria is the determination of the state of immunity of the population. Judging by the numerous publications [4-5], the number of immune persons and the level of antibodies in them in different years and in certain territories are different. Given that the highest incidence is currently observed among adults, we decided to study the state of protection not of the total population, but of adults. The intensity of immunity to diphtheria and tetanus in the adult population of Kazan was studied by us in 1992 against the background of epidemic well-being, at that time in Moscow, St. Petersburg, Moscow, Leningrad, Irkutsk regions, Primorsky Krai, there was a significant increase in the incidence of diphtheria.

A dry differential semi-synthetic medium to distinguish meningococci from non-pathogenic Neisseria was tested with 306 freshly isolated Neisseria strains. Tests have shown the high diagnostic value of the environment. It is convenient to prepare and easy to use.

Tension of antidi phtheria immunity among uninoculated persons in various indicatory groups of population of Tatarstan Republic in the presence of epidemic process intensification is studied. It is revealed that in 44,576,5% of uninoculated inhabitants in various indicatory groups and classes of population the titers were lower than protective. Taking into account a large percent of unprotected persons and absence of financial and material possibilities of determining the immunity level before inoculation the practice of performing thrice-repeated inoculation of adults older than 30 is justified.