The Mumps Outbreak Epidemiology in Zambezi Region

Background and aim: Mumps is a vaccine-preventable viral disease characterized by swelling of the salivary glands and potential complications. beginning February 13, 2023, an outbreak of mumps occurred in Zambezi Region, Namibia, and is ongoing. We investigated to describe the epidemiology of the outbreak, actively identify cases, implement health interventions, and inform effective public health strategies. Material and Methods: A descriptive cross-sectional study was conducted to analyse mumps cases in the Zambezi region. Clinical diagnoses case definition was used. A clinical case was defined as acute onset of gland swelling lasting ≥2 days. Data were collected from health facilities and schools, including demographic information and diagnosis. A line list was generated, and data were analysed descriptively using descriptive model. Results: A total of 2625 mumps cases were reported in the Zambezi Region, between February 13th, 2023, and October 8th, 2023. Interventions included active case searches, supportive treatment, health education, and advising patients to self-isolate for 7 days. Age group under five years experienced the highest attack rate 3.62%, followed by under 15 years with 2.98% and the least attack rate was observed in 15 years and above with 0.80%. Females experienced slightly higher infection rates at 50.1%. Zambezi region saw a significant number of mumps cases reported in various villages, Chotto led the list with 308 cases, followed by Cowboy with 246 cases. The outbreak displayed progressively increasing peaks in the epidemiological curve, indicating ongoing transmission. No fatalities and complications were reported, p < 0.01). Discussion: The outbreak mainly impacted school-aged children. No deaths or severe cases occurred. The lack of mumps vaccination in the national program might have amplified the outbreak. To address Zambezi's situation, introducing mumps vaccination and including it in surveillance for early detection is crucial. Ongoing case searches and immediate isolation remain essential.