7g - Evaluation of the measles surveillance system in Tashkent, Uzbekistan, 2023

Background : Measles is a highly contagious, vaccine-preventable disease. In 2023, in Uzbekistan, where reported measles vaccine coverage is 99%, there was an increase in measles incidence (8,670 cases; 24.1 per 100,000 population). We aimed to identify gaps in the measles surveillance system in Tashkent.

Methods : We conducted a descriptive cross-sectional surveillance evaluation study in three healthcare facilities and the Committee for Sanitary-Epidemiological Welfare and Public Health of Tashkent City from January to April 2024. We reviewed case reports, medical and epidemiologic investigation cards from 200 patients registered for 2023.

Results : Notification and case record forms are entirely paper-based. Knowledge of reporting norms and the standard case definition of measles among interviewed providers (n=50) was 65%. Of the reported cases (n=200), 22% were from polyclinics and 79% from an infectious disease hospital.  Several data errors were found among reported cases: 2% (4/200) had incorrect sex, 3% were missing age or contact number, 5% were missing work/study place or had the wrong date of sampling, and 7% were missing the date of onset. Case notification reports were submitted late (>72 hours) in 19% of cases. Epidemiologic investigations were initiated late (>96 hours) in 21% of cases. The collection of blood samples for laboratory testing was late in 2% of cases. Among cases, 4% had documented previous measles vaccination, and 3% had no vaccine status. We identified no cases of measles that were not reported, and all reported cases met the case definitions (sensitivity and positive predictive value = 100%).

Conclusions The surveillance system is accurately detecting measles cases. We identified important gaps in data quality and timeliness. Adoption of an electronic data system may help improve data quality and timeliness.