Background: Dengue fever is an infectious disease of global health concern. This study aimed to describe the epidemiology and field experience of a locally transmitted outbreak of dengue fever in Muscat Governorate, Oman from mid-March to mid-April 2022, and the multi-sectoral approach to control the outbreak.
Methods: Data were collected from an electronic e-notification system, active surveillance and contact investigations.
Results: Of 250 suspected and probable cases, 169 were confirmed as dengue fever with DENV-2 serotype. Of these, 108 (63.9%) were male and 94 (55.6%) were Omani. The mean age was 39 years (standard deviation 13 years). Fever was the most common symptom and occurred in 100% of cases. Haemorrhagic manifestations occurred in 10% (n=17) of cases. Hospitalization was required for 93 cases (55.1%). The field investigation included 3444 houses and other suspected sites. Breeding sites for Aedes aegypti were identified in 565 (18.5%) sites visited. Interventions to control the outbreak included environmental and entomological assessment of the affected houses and surrounding areas (400 m radius of each house).
Conclusion: Outbreaks are expected to continue, with the possibility of severe cases due to antibody-dependent enhancement. More data are required to understand the genetics, geographical spread and behaviour of A. aegypti in Oman.
Keywords: Aedes aegypti; Antibody-dependent enhancement; Dengue fever; Mosquito; Muscat; Oman; Outbreak; Seroprevalence.
© 2023 The Authors.