Towards an understanding of resurgent measles outbreaks in Kismayo, Somalia: A mixed method investigation of measles burden and vaccination coverage during a 2020-2021 measles outbreak

BACKGROUND AND OBJECTIVES
Kismayo is a city in southern Somalia and the capital of Jubaland State. In 2020, the Jubaland State Ministry of Health (MoH) recorded 1094 measles cases: an 8.2-fold increase from 2019. This study sought to estimate measles disease burden and measles vaccination coverage during the 2020-2021 outbreak, while further identifying key barriers and facilitators to measles vaccination and care.

METHODS
We utilised a sequential mixed-method approach with two phases of data collection. Phase one involved a cross-sectional household survey with a standard questionnaire while phase two included key informant interviews and focus group discussions with community members, health care workers and vaccination program administrators.

RESULTS
Of 6664 individuals, 338 measles cases were recorded during the two-year recall period, giving an attack rate of 5% (95%CI:4-5). 17 measles deaths were reported, giving a case fatality ratio of 4% (95%CI:2-6). Measles-specific mortality was 0.04 deaths/day/10000 population (95%CI:0.02-0.05). Initially, 50% of vaccine-eligible children had one or more doses of measles containing vaccine (MCV) and this rose to 69% by the end of the recall period. Thematic analysis led to the grouping of qualitative data into two overarching themes: sociocultural factors and health system factors. Regarding sociocultural factors, respondents gave insights on community measles knowledge and care practices, social responsibility for prevention, security challenges and measles-related rumours. Regarding health system factors, respondents spoke about challenges with health service management and shortcomings in the implementation of the expanded programme on immunisation (EPI) and mass vaccination campaigns.

CONCLUSIONS
Our results show that measles represents a serious health burden for the Kismayo population and that MCV coverage is well below the 95% target for herd immunity. We recommend developing a population-specific approach to risk communication and community engagement, expanding measles care, increasing accessibility for EPI services in health facilities and mobile clinics, and developing improved programmatic strategies for mass vaccination campaigns.