FACTORS ASSOCIATED WITH MEASLES INFECTION IN BORDER AND NON-BORDER DISTRICTS OF SIERRA LEONE

Abstract

Background: Sierra Leone has recorded multiple outbreaks of measles, and the last three outbreaks (2018, 2019, 2022) were reported from point-of-entry communities. Until now, limited information exists on the burden of measles in border and non-border districts. This study aimed to describe the epidemiological trend, vaccination status, incidence, and factors associated with measles infection in border and non-border districts of Sierra Leone.

Methods: We conducted a retrospective secondary data analysis on measles case-based surveillance data from 2018 to 2021 extracted from the national line list and the District Health Information System database. We use the measles standard case definition to classify cases across border districts and non-border districts. Logistic regression was used to identify factors associated with measles infection.

Result: A total of 3,054 suspected measles cases were recorded, of which 1147 (38%) were positive for measles infection with a median age of 9 years (6 months to 37 years). Among the positive cases, 448 (39%) were vaccinated and border districts accounted for 438 (38.1%). The measles incidence in border districts ranges from 3 to 11 per 100,000 population, whilst in non-border districts it ranges from 1 to 3 per 100,000 population.

Conclusion: A high incidence of measles cases were recorded in border districts and the vaccination status among susceptible was low. We recommend intensifying regular and supplemental immunization activities targeting border and non-border districts in Sierra Leone.

Keywords: Measles, Incidence, vaccination, Border and non-border districts, Sierra Leone.