Gareth J Hughes1, Amy F W Mikhail, Dominicus Husada, Eveline Irawan, George Kafatos, Samantha Bracebridge, Richard Pebody, Androulla Efstratiou. 1. From the *Field Epidemiology Training Programme, Public Health England, London, United Kingdom; †Academic Unit of Public Health, Leeds Institute of Health Sciences, University of Leeds, Leeds, United Kingdom; ‡European Programme for Public Health Microbiology Training, European Centres for Disease Prevention and Control, Stockholm, Sweden; §World Health Organisation Collaborating Centre for Reference and Research on Diphtheria and Streptococcal Infections, Public Health England, London, United Kingdom; ¶Airlangga University, Surabaya, Indonesia; ‖Balai Besar Laboratorium Kesehatan, Surabaya, Indonesia; and **Public Health England, London, United Kingdom.
Abstract
BACKGROUND: In 2012, an ongoing outbreak of diphtheria in Indonesia was focused in the province of East Java. There was a need to assess vaccine coverage and immunity gaps in children. METHODS: We conducted a cross-sectional seroprevalence and vaccine coverage survey of children 1-15 years of age in 2 districts of East Java: one of high incidence (on the island of Madura) and one of low incidence (on the mainland). From each district, we sampled 150 children (10 children per year of age). Sera and throat swabs were taken to determine immunity and carriage status. Immunity was defined as ≥0.1 international unit/mL of antibody to diphtheria toxin. RESULTS: A total of 297 children were selected to participate in the study. Coverage of three doses of combined vaccine for diphtheria, tetanus and pertussis was significantly lower (P < 0.001) in the high incidence district compared with the low [57%, 95% confidence interval (CI): 36-78 vs. 97%, 95% CI: 93-100]. Despite this higher vaccine coverage, seroprevalence of immunity was lower in the low incidence district compared with the high (71%, 95% CI: 63-80 vs. 83%, 95% CI: 76-90). Immunity in the high incidence district was associated with increased age, increased prevalence of toxigenic Corynebacterium diphtheriae carriers and with receipt of multiple (and likely more recent) boosters. CONCLUSIONS: Significant variation exists in vaccine coverage and seroprevalence of immunity to diphtheria in East Java. Immunity in high incidence districts is likely because of natural immunity acquired through exposure to toxigenic C. diphtheriae. Booster vaccines are essential for achieving protective levels of immunity.
BACKGROUND: In 2012, an ongoing outbreak of diphtheria in Indonesia was focused in the province of East Java. There was a need to assess vaccine coverage and immunity gaps in children. METHODS: We conducted a cross-sectional seroprevalence and vaccine coverage survey of children 1-15 years of age in 2 districts of East Java: one of high incidence (on the island of Madura) and one of low incidence (on the mainland). From each district, we sampled 150 children (10 children per year of age). Sera and throat swabs were taken to determine immunity and carriage status. Immunity was defined as ≥0.1 international unit/mL of antibody to diphtheria toxin. RESULTS: A total of 297 children were selected to participate in the study. Coverage of three doses of combined vaccine for diphtheria, tetanus and pertussis was significantly lower (P < 0.001) in the high incidence district compared with the low [57%, 95% confidence interval (CI): 36-78 vs. 97%, 95% CI: 93-100]. Despite this higher vaccine coverage, seroprevalence of immunity was lower in the low incidence district compared with the high (71%, 95% CI: 63-80 vs. 83%, 95% CI: 76-90). Immunity in the high incidence district was associated with increased age, increased prevalence of toxigenic Corynebacterium diphtheriae carriers and with receipt of multiple (and likely more recent) boosters. CONCLUSIONS: Significant variation exists in vaccine coverage and seroprevalence of immunity to diphtheria in East Java. Immunity in high incidence districts is likely because of natural immunity acquired through exposure to toxigenic C. diphtheriae. Booster vaccines are essential for achieving protective levels of immunity.
Authors: Nobuo Saito; Virginia O Dimapilis; Hiroshi Fujii; Motoi Suzuki; Elizabeth Freda O Telan; Dorcas Valencia Umipig; Rontgene M Solante; Alexis Q Dimapilis; Ferdinand De Guzman; Eumelia P Salva; Fumihito Nakayama; Kohei Toda; Chris Smith; Koya Ariyoshi; Christopher M Parry Journal: Clin Infect Dis Date: 2021-01-23 Impact factor: 9.079
Authors: Vernon Jian Ming Lee; Yee Sin Leo; Li Wei Ang; Qi Gao; Lin Cui; Aysha Farwin; Matthias Paul Han Sim Toh; Irving Charles Boudville; Mark I-Cheng Chen; Angela Chow; Raymond Tzer-Pin Lin Journal: BMC Public Health Date: 2022-01-16 Impact factor: 3.295