@article{oai:nagasaki-u.repo.nii.ac.jp:00027822,
 author = {Kitamura, Noriko and Hoan, Thanh T. and Do, Hung M. and Dao, The A. and Le, Lien T. and Le, Thao T.T. and Doan, Thuy T.T. and Chau, Thuong N. and Dinh, Hoi T. and Iwaki, Masaaki and Senoh, Mitsutoshi and Efstraciou, Androulla and Ho, Nen M. and Pham, Duc M. and Dang, Duc-Anh and Toizumi, Michiko and Fine, Paul and Do, Hung T. and Yoshida, Lay-Myint},
 issue = {1},
 journal = {Emerging Infectious Diseases},
 month = {Dec},
 note = {In 2019, a community-based, cross-sectional carriage survey and a seroprevalence survey of 1,216 persons 1–55 years of age were conducted in rural Vietnam to investigate the mechanism of diphtheria outbreaks. Seroprevalence was further compared with that of an urban area that had no cases reported for the past decade. Carriage prevalence was 1.4%. The highest prevalence, 4.5%, was observed for children 1–5 years of age. Twenty-seven asymptomatic Coerynebacterium diphtheriae carriers were identified; 9 carriers had tox gene–bearing strains, and 3 had nontoxigenic tox gene–bearing strains. Child malnutrition was associated with low levels of diphtheria toxoid IgG, which might have subsequently increased child carriage prevalence. Different immunity patterns in the 2 populations suggested that the low immunity among children caused by low vaccination coverage increased transmission, resulting in symptomatic infections at school-going age, when vaccine-induced immunity waned most. A school-entry booster dose and improved infant vaccination coverage are recommended to control transmissions., Emerging Infectious Diseases, 29(1), pp.70-80; 2022},
 pages = {70--80},
 title = {Seroepidemiology and Carriage of Diphtheria in Epidemic-Prone Area and Implications for Vaccination Policy, Vietnam},
 volume = {29},
 year = {2022}
}