Abstract
Purpose To investigate the immunity of Diptheria from Corynebacterium diphtheriae, pertussis from Bordetella pertussis and tetanus from Clostidium tetani in Thais Subject and method Firstly, commercial kit for the detection of antibodies to diphtheria, tetanus and pertussis using indirect ELISA (EUROIMMUN, Germany) were pre-evaluated. Secondly, the seroprevalence of antibodies to diphtheria toxin IgG (anti-DT), tetanus toxin IgG (anti-TT) pertussis toxin IgG (anti-PT) were performed in 965 sera from blood volunteers in 2014, aged between <20 and >60 years, who attending at regional blood center from the North (240 sera from Chiangmai, Pitsanulok, Lampang and Nakon Sawan provinces), the Central (243 sera from Lopburi, Ratchaburi, Chonburi and Bangkok provinces), the Northeastern (240 sera from Khonkaen, Nongkhai, Nakhon Phanom and Ubon Ratchatani provinces) and the South parts (242 sera from Krabi, Songkha, Pattani and Prachuap Khiri Kan provinces). Result Overall the seroprevalence at the protective level (>0.1 IU/ml) of anti-DT was 62.9% [GMT (geometric mean titer) 0.19 IU/ml, 95%CI 0.13-0.25)] and anti-TT was 87.8% (GMT 1.16, 95%CI 0.73-1.59). Anti-DT level from provinces in the South was higher than other parts (p<0.05, Chi square and Kruskal Wallis). Anti-DT level in Bangkok was the lowest prevalence (43.3%) and low anti-DT level might be seen at all age groups in some area such as Nakornsawan, Lopburi and Ubonrachatanee provinces. Regarding to pertussis, no information of the protective level of anti-PT was documented. In this study, the prevalence of anti-PT was 52% based on the presence of antibody in subjects bearing at 5 IU/ml (criteria for vaccine trial) and was only 12.9% based on antibody at 40 IU/ml (criteria for diagnosis based on kit) with GMT of anti-PT 10.16 (95%CI 6.93-13.39). This will be implied that Thai population might be risk of pertussis due to low prevalence of anti-PT antibody. No significant difference of gender was found in these 3 specific antibodies. Conclusion The information from this study might be the useful for the consideration to stimulate the immunity by vaccination at high risk group of waning antibodies. In Thailand, booster vaccination against diphtheria, tetatnus and including pertussis should be considered in Thai adult.
