Dengue Fever: An Emerging Disease in Oman Requiring Urgent Public Health Interventions

Abstract

Dengue, the most widespread mosquito-borne viral infection in humans, is an emerging public health problem in countries of the Eastern Mediterranean region threatening national, regional, and global health security. The disease is endemic in more than 128 countries in the African, Americas, Eastern Mediterranean, Southeast Asian, and the Western Pacific regions with estimates of 390 million cases representing 17% of the global burden of infectious diseases in 2013. Outbreaks and sporadic cases of dengue, dengue-like disease, and dengue hemorrhagic fever (DHF) have been reported across the Eastern Mediterranean region, from Pakistan, Saudi Arabia, Yemen, Somalia, Sudan, Djibouti, and Oman (travel-related). Dengue fever (DF) is a self-limiting illness with clinical manifestations evoking a common viral illness. However, a few patients will develop DHF, which is a serious and potentially life-threatening disease. Aedes aegypti is the primary vector transmitting the dengue virus and three other viruses causing yellow fever, chikungunya, and Zika fever. In Oman, DF and DHF are notifiable diseases. Between 2001 and 2017, 173 cases were reported, and all were travel-related. Between 2013 and 2017, the annual notification rate of dengue exhibited an upward trend from 0.3 to 1 per 100 000 population, and the case fatality rate was 0.01%. Cases were mainly reported from the Muscat (9.6/100 000), Dhofar (2.4/100 000), and North Batinah (2/100 000) governorates. Ninety-five percent of cases were foreign-born adults from India, Sri Lanka, Pakistan, and other Asian nationalities. Only two indigenous cases of DF were reported both from the Dhofar governorate; a suspected case in 2004 and a confirmed case in 2009. In 2018, a total of 67 DF cases were notified, of which 30 cases (44.8%) were travel-related. None developed DHF, and no mortality was recorded. Between 12 November 2018 and 6 January 2019, 40 indigenous DF cases were reported and confirmed. The first case could be an index case exposed to mosquitoes infected from an asymptomatic viremic traveler residing in the same area. Given the imminent current outbreak in Oman, there is an urgent need to step-up an efficient entomological surveillance system guiding the program on vector control interventions. Control of dengue also requires a sustained national commitment, concerted actions by multidisciplinary and intersectoral collaborations from civil society and communities, and sound technical support at the local level to channel resources effectively. Strategies for vector control should focus on source reduction of the urban habitats of competent vectors and careful environment management to deprive the A. aegypti of stagnant water for breeding.

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