title: Seroprevalence of tetanus antibody in the Thai population: a national survey.
abstract: Tetanus is a disease with high mortality and the most important measure for effective prevention is vaccination. Tetanus immunization has been introduced to Thailand's national immunization program for 30 years. Yet, the coverage and seroprevalence of tetanus antibody in vast parts of the population has not been assessed. This study has been performed on 1,277 subjects aged between 6 months and 60 years or above from four geographically distinct provinces of Thailand. Tetanus antibody levels were measured using a commercially available ELISA kit. Most of the Thai population had immunity against tetanus. The level of antibodies to tetanus, as demonstrated by the geometric mean titer of antibody (GMT) (and 95% confidence interval) was 2.62 (2.34-2.91) IU/ml. The highest and lowest GMT was found in subjects aged between 5 and 9 years, and above 60 years of age with GMT (and 95% confidence intervals) of 3.64 (3.34-3.96) and 1.24 (0.67-2.29) IU/ml respectively. The minimum protective level of antitoxin (>0.01 IU/ml) was detected in 99.7 % of subjects. More than 90% of subjects displayed durable antibody protection levels (DAPL) (> or = 1.0 IU/ml), except for subjects above the age of 60 years (82%). According to this study, the majority of the population expresses tetanus antibody levels that can confer long term protection. Yet, considering the lowest GMT and the highest incidence of tetanus cases found in subjects aged above 60 years, re-immunization should be targeted at this age group especially if they had sustained any tetanus-prone injury.
authors.affiliation: Center of Excellence in Clinical Virology, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Rama IV Road, Patumwan, Bangkok 10330, Thailand.
authors.forename: Pantipa
authors.initials: P
authors.lastname: Chatchatee
authors.forename: Susheera
authors.initials: S
authors.lastname: Chatproedprai
authors.forename: Porpit
authors.initials: P
authors.lastname: Warinsathien
authors.forename: Piyanit
authors.initials: P
authors.lastname: Tharmaphornpilas
authors.forename: Pornsak
authors.initials: P
authors.lastname: Yoocharoen
authors.forename: Sirisak
authors.initials: S
authors.lastname: Warintrawat
authors.forename: Apiradee
authors.initials: A
authors.lastname: Theamboonlers
authors.forename: Voranush
authors.initials: V
authors.lastname: Chongsrisawat
authors.forename: Yong
authors.initials: Y
authors.lastname: Poovorawan
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000907:Antibodies, Bacterial / Q000097:blood* / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D003625:Data Collection; D005260:Female; D006801:Humans; D007114:Immunization; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D016036:Seroepidemiologic Studies; D013742:Tetanus / Q000097:blood* / Q000453:epidemiology* / Q000276:immunology / Q000517:prevention & control; D013785:Thailand
chemical_list: D000907:Antibodies, Bacterial