An Outbreak Investigation of Mumps in Eastern Nepal – An Observational Study

Abstract                                                                                                                                                                  Introduction: Mumps is an acute viral infection caused by a paramyxovirus. Mumps outbreak has been observed in different parts of the world, recently an outbreak was observed in South Africa on May 2023. Although, Mumps is a vaccine preventable disease it has not been included in the routine immunization schedule of Nepal as well as it does not fall under the category of notifiable disease. Complication of Mumps has been observed from children to adults leading to burden in the family and society. The study was done to investigate the burden of mumps in eastern Nepal from May, 2023 to October, 2023. Method: This was an observational, descriptive study, done in pediatric department of BMCTH from May to October, 2023. 160 children, up to the age of 14 years were clinically diagnosed as Mumps and outbreak was confirmed by PCR testing of Buccal swab.                                                                                                                                                                        Results: Mumps outbreak peak was observed from May-October, 2023, with the incidence of 160 cases. Affected children were mostly belonging to Morang district (108,68%) followed by Sunsari (43,27%). Incidence of disease occurred mostly in school (129;81%). Most commonly affected children were of age group of 5-9 years. None of the children were vaccinated against mumps. Parotid swelling was the most common presenting complaint which occurred in all children (160;100%) followed by fever (138;86.3%). 104(64.4%) children developed bilateral parotid swelling while (57, 35.6%) children unilateral. Conclusion: Lack of Mumps Vaccination, overcrowding and no event-based surveillance for prompt outbreak detection and response were causes of mumps outbreak. Key words:  Mumps; Outbreak; Nepal