[Immunity to diphtheria in population of Rostov-on-Don city and Rostov region in recent years].

AIM: To study the magnitute of antitoxic immunity against diphtheria in different age groups of Rostov-on-Don city and Rostov region population. MATERIALS AND METHODS: Antitoxic immunity against diphtheriawas studied in children 3 - 15 years old (661 persons) and adults 16 - 59 y.o. (893 persons), which were tested during 2003 - 2007 using direct hemagglutination assay manufactured by Mechnikov Scientific Production Association "Biomed" (Moscow). RESULTS: Proportion of children 3 - 15 y.o. seropositive to diphtheria was 98.6 +/- 0.5%. Children aged 3 years and 4 - 6 years were identified as a risk group for diphtheria as they had highest proportions of non-immune persons. Proportion of immune to diphtheria in adults was 94.4 +/- 0.8%. Maximal level of protection was observed in personsaged 16 - 17and 18 - 19 years, in which the proportion of seropositive persons was 99.1 - 100%. Persons > or = 50 years old formed group of risk because persons with low or moderate titers of antitoxin were identified in this age group mostly. CONCLUSION: Obtained results provide evidence on enough high level of protection of Rostov-on-Don cityand Rostov region population against diphtheria. Group of increased risk comprised of persons aged 3 - 6 years and > or = 50 years.