IGG SPECIFIC LEVELS FOR DIPHTHERIA, TETANUS AND PERTUSSIS IN RURAL AND URBAN SAMPLES IN ALBANIA

Abstract

INTRODUCTION: During the years 1970s and 1980s, IPH (Institute of Public Health) in Albania, achieved remarkable improvements in the biotechnology of the components production of D (diphtheria), T (tetanus) and P (pertussis) for the trivalent vaccine DTP, vaccine DT and the Td one, which together with vaccine TT, consequently led to the increasing of their effectiveness and efficiency. In the year 2000, Rubella component was added to Measles vaccine, and in the year 2005, Mumps component was added too (now MMR vaccine).OBJECTIVE: The primary objective of this study was to identify protective immunoglobulin G (IgG) levels for each antigen (diphtheria, tetanus, and pertussis) according to different age groups and residence (rural and urban).METHODS: Two samples, each involving 120 healthy children were selected from urban and rural populations of three central regions of Albania. The children were aged between 1 and 15 years. IgG specific levels for diphtheria, tetanus, and pertussis were measured using enzyme-linked immunosorbent assay tests (ELISA). Levels of IgG were classified into the following categories: unprotected, insufficient, and fair/good or full/sure protection, using specific thresholds for each, diphtheria, tetanus, and pertussis.RESULTS: Of the same population, 75.7% was found to have IgG protective levels for diphtheria. For tetanus, 81.4% of the total sample had protective levels of IgG, and for pertussis this proportion was 69.0%.Levels of protection for diphtheria and tetanus increased up until  3 years of age (diphtheria: 25.0% at 1 year and then 95.0% at 3 years of age; tetanus: 65.0% at 1 year and 90.0% at 3 years of age). From then on the trend stabilized. The same trend was not observed for pertussis, which presented protective IgG levels of 73.0% from the first year of life. When IgG protective levels were compared between rural and urban samples, differences were only found with diphtheria specific IgG, which was significantly higher in the rural population. Furthermore, a correlation in IgG levels was found among diphtheria and tetanus.CONCLUSIONS: IgG specific levels for diphtheria, tetanus and pertussis referring to our sample are are considered acceptable for providing protection in the general population. Nevertheless, these levels seem to have been achieved only after booster doses until the third year of life, especially for diphtheria.