PLoS Med

BackgroundDuring August 2017\u2013January 2018, more than 700,000 forcibly displaced Rohingyas crossed into Cox\u2019s Bazar, Bangladesh. In response to measles and diphtheria cases, first documented in September and November 2017, respectively, vaccination campaigns targeting children 6 years were not assessed. In MSs, measles seroprotection was similarly high among 1- to 6-year-olds and 7- to 14-year-olds (91% [95% CI 86%\u201394%] and 99% [95% CI 96%\u2013100%], respectively, p < 0.001). Rubella and diphtheria seroprotection in MSs were significantly lower among 1- to 6-year-olds (84% [95% CI 79%\u201388%] and 63% [95% CI 56%\u201370%]) compared to 7- to 14-year-olds (96% [95% CI 90%\u201398%] and 77% [95% CI 69%\u201384%]) (p < 0.001). Tetanus seroprevalence was similar among 1- to 6-year-olds and 7- to 14-year-olds (76% [95% CI 69%\u201381%] and 84% [95% CI 77%\u201389%], respectively; p = 0.07). Vaccination campaign coverage was consistent with seroprotection in both camps. However, nonresponse, the main limitation of the study, may have biased the seroprotection and campaign coverage results.ConclusionsIn this study, we observed that despite multiple vaccination campaigns, immunity gaps exist among children in MSs, particularly for diphtheria, which requires serial vaccinations to achieve maximum protection. Therefore, an additional tetanus-diphtheria campaign may be warranted in MSs to address these remaining immunity gaps. Rapid scale-up and strengthening of routine immunization services to reach children and to deliver missed doses to older children is also critically needed to close immunity gaps and prevent future outbreaks.Why was this study done?What did the researchers do and find?What do these findings mean?001/WHO_/World Health Organization/International32231368PMC7108726822