Measles disease outbreak and genotype identification in Libya, 2018

Background: There is no data published related to measles outbreaks in Libya. The study aims to report a descriptive analysis of measles outbreaks that occurred in 2018. Methods: Retrospective data of measles outbreaks in 2018 were analysed to describe the characteristics of the outbreaks and their incidence in Libya. Data aggregations of seven outbreaks were extracted during the period January to December 2018 from the National Measles Surveillance Programme which is the official institute responsible for measles surveillance in the country. Data were categorised as confirmed measles cases, district distribution, deaths, age distribution, sex ratio, monthly trends, and measles vaccination status in the outbreaks. Also, the measles virus genotype was identified and compared with the reference strain. Results: A total of 934 confirmed measles cases were detected in seven outbreaks in different locations of the country in 2018. The biggest outbreak was found in Zliten (449 measles cases, 48.0%) followed by  Benghazi (374 measles cases, 40.0%). The majority were below 15 years (811 measles cases, 87.0%). The incidence rate of cases was 223/million population. The peak of occurrence began in June 2018 and continued to December. Children with measles who had completed two doses of vaccines were 18.0%, whilst 62.0% were unvaccinated. The genotype sequence was identified in three outbreaks being B3.  Conclusion: A significant measles incidence was detected in many outbreaks mainly in the age group below 15 years. The immunity building programme must be evaluated to address the weakness of routine immunisation.