Lessons Learned from an Underreported Mumps Epidemic Among Rohingya Refugees, Cox’s Bazar, Bangladesh

Background: In 2018 a large mumps epidemic coincided with an outbreak of diphtheria in refugee camps established in Bangladesh for the Rohingya people. These refugees did not receive a mumps containing vaccine. Methods: Cases of mumps were reported to the World Health Organisation (WHO) Early Warning, Alert and Response System (EWARS) during the Rohingya refugee crisis. The authors present amalgamated epidemiological data of a major, previously unreported, mumps epidemic. Results: In total 19 215 mumps cases across a total of 218 facilities were reported to EWARS during 2018. The attack rate was 2.1% of the whole population. 7 687 (40·0%) of these cases were in children under 5 years old. Mumps was more commonly seen among males than females. Conclusion: Detailed reporting of outbreaks of all vaccine preventable diseases is essential to ensure appropriate vaccination decisions can be made in future humanitarian crises