Securing long-term immunity: The possible necessity of supplementary measles vaccination.

Background: The global initiative to eliminate measles, spearheaded by the World Health Organization, has yet to achieve its intended goals. In Turkey, despite robust vaccination strategies, recent increases in measles cases have been attributed to vaccine hesitancy and irregular migration. This study evaluates measles serology within a pediatric population to determine the impact of vaccination regimens on immunity.
Methods: A retrospective study at Ankara Bilkent City Hospital analyzed serum measles IgG levels in children aged 1-18 years from January 2020 to August 2023. Exclusions were applied for individuals with positive IgM results, incomplete vaccinations, and immunocompromised conditions. Patients were categorized based on their M-M-R ^® II vaccine status into those having received either one or two doses. Seropositivity was assessed using the ELISA method.
Results: Of the 686 children, 30.2% received a single dose, and 69.8% received two doses of the MMR vaccine. Overall, 70.7% exhibited positive IgG levels. No significant differences were found in IgG levels between those who received one dose and those who received two doses. However, a decline in IgG levels was observed with age, particularly notable in adolescents aged 14-18 years.
Conclusion: The study reveals seropositivity rates lower than expected, highlighting challenges in achieving WHO targets. This suggests a potential need for booster doses during adolescence to maintain protective antibody levels. The findings emphasize the importance of continued surveillance and research to adapt vaccination strategies effectively and prevent measles outbreaks, particularly considering the decline in antibody levels and diverse vaccination histories across populations.
Competing Interests: Declarations Ethics approval and consent to participate This study was conducted in accordance with the ethical standards of the institutional and national research committees, and with the 1975 Helsinki Declaration and its later amendments. Ethical approval was granted by the Ethics Committee of Ankara Bilkent City Hospital. Where applicable, general consent for the use of medical records in research was obtained as part of the admission process. Consent for publication No interventions were performed on any patients for the purposes of this study; only existing medical records were utilized. Data was anonymized and confidentiality was maintained in compliance with ethical standards. The information used was in accordance with the general consent provided by patients at the time of their admission to the hospital. Competing interests The authors declare no competing interests. Clinical trial registration This study does not involve any clinical trials. Therefore, no clinical trial registration is required.
(© 2024. The Author(s).)