In December 2018, routine surveillance identified an autochthonous outbreak of dengue fever in Muscat Governorate, Oman, a region previously free of dengue fever. Routine surveillance confirmed locally acquired cases in the second week of December, leading to a rapid public health response including case management guidance and epidemiological investigations. The main activity was the vector survey using systematic sampling to assess extent of previously unreported Aedes aegypti presence followed by a campaign aimed to eliminate breeding sites of A. aegypti". During a 5-month period, 343 suspected cases were reported from Muscat Governorate with 122 from the outbreak affected area. Out of 207 probable cases eligible for laboratory testing as per guidelines issued, 59 cases were confirmed. The vector elimination campaign started on January 8, 2019 after a media advocacy using television and social media and concluded on January 23. By the end of campaign, the case load had decreased significantly in the affected area with no reports of locally acquired cases from adjoining areas of Muscat Governorate, indicating no further spread. Rapid notification and early community-wide, extensive vector control activities effectively contained the autochthonous dengue fever virus outbreak.

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has been proven to be lethal to human health, which affects almost every corner of the world. The objectives of this study were to add context to the global data and international genomic consortiums, and to give insight into the efficiency of the contact tracing system in Oman. We combined epidemiological data and whole-genome sequence data from 94 samples of SARS-CoV-2 in Oman to understand the origins, genetic variation, and transmissibility. The whole-genome size of sequence data was obtained through a customized SARS-COV-2 research panel. Amplifier methods ranged from 26 Kbp to 30 Kbp and were submitted to GISAID. The study found that P323L (94.7%) is the most common mutation, followed by D614G (92.6%) Spike protein mutation. A unique mutation, I280V, was first reported in Oman and was associated with a rare lineage, B.1.113 (10.6%). In addition, the study revealed a good agreement between genetic and epidemiological data. Oman’s robust surveillance system was very efficient in guiding the outbreak investigation processes in the country, the study illustrates the future importance of molecular epidemiology in leading the national response to outbreaks and pandemics.

Following the detection of the first human case of avian influenza A subtype H9N2 in 1998, more than 40 cases were diagnosed worldwide. However, the spread of the virus has been more remarkable and significant in global poultry populations, causing notable economic losses despite its low pathogenicity. Many surveillance studies and activities conducted in several countries have shown the predominance of this virus subtype. We present the case of a 14-month-old female in Oman with an A(H9N2) virus infection. This is the first human case of A(H9N2) reported from Oman and the Gulf Cooperation Countries, and Oman is the second country outside of southern and eastern Asia to report a case (cases have also been detected in Egypt). The patient had bronchial asthma and presented with a high-grade temperature and symptoms of lower respiratory tract infection that necessitated admission to a high dependency unit in a tertiary care hospital. It is of urgency that a multisector One Health approach be established to combat the threat of avian influenza at the animal-human interface. In addition to enhancements of surveillance and control in poultry, there is a need to develop screening and preventive programs for high-risk occupations.

HIV prevalence in Oman is low (5 %). HIV screening is performed at regional public health laboratories as part of a medical fitness programme for residency applicants. We conducted a retrospective evaluation of indeterminate serology results from 11 females of African origin, aged 21–43 years. Serology testing for HIV was conducted according to the national Oman algorithm: fourth-generation immunoassays (Bio-Rad GS HIV Combo Ag/Ab EIA, Siemens Enzygnost HIV Integral 4, Abbott ARCHITECT HIV Ag/Ab Combo, Roche Elecsys HIV Combi PT, bioMérieux VIDAS HIV DUO QUICK), confirmatory assays (Geenius HIV 1/2 Confirmatory, INNO-LIA HIV I/II Score) and PCR testing. Confirmatory testing to resolve indeterminate results was conducted with available samples for five patients using a combination of immunoassays, confirmatory assays, PCR/PERT and pro-viral DNA levels, at three external laboratories; Roche Diagnostics (Germany), Swiss National Laboratory (Switzerland) and Barts Health NHS Trust (UK). Nineteen serum, 15 plasma and two whole-blood samples were analysed. Nine of ten patients analysed on Bio-Rad and Siemens immunoassays were highly reactive; seven were highly reactive on the Abbott assay. Eight of nine patients tested with the Roche assay were negative. Three of four patients tested on the bioMérieux assay were negative. Five patients underwent confirmatory testing at external laboratories; all were negative by HIV-RNA or pro-viral DNA testing. In conclusion, HIV-RNA and pro-viral DNA testing is recommended for HIV screening of individuals from high-prevalence regions coming to low-prevalence regions.

Mucormycosis is a rare, severe fungal infection mainly affecting immunocompromised individuals. Because of limited data on its epidemiology in Oman, we present this national, multicentric, retrospective review that includes all cases of proven mucormycosis between 2006 and 2022 in Oman. There were 51 cases of mucormycosis reported in Oman. The annual incidence of mucormycosis was 0.38–0.69 cases per million population before COVID-19. During the pandemic, the incidence rose significantly to 1.76 in 2020, 5.31 in 2021, then decreased to 0.87 per million population in 2022. Diabetes was observed in 82.4% (n = 42) of the cases, COVID-19 in 47.1% (n = 24), and other chronic diseases in 72.6%. The use of steroids was reported in 33.3% (n = 17) and many patients (64.7%, n = 33) had multiple risk factors. The overall mortality rate was 41.2% (n = 21) and most deaths occurred within a month of diagnosis. Mortality rate among patients diagnosed with COVID-19 was 58.3% (14/24). Survival analysis showed a statistically significant association between COVID-19 status and patient survival (p = 0.024). Annual incidence of mucormycosis in Oman rose during the pandemic. This study highlights the epidemiological features of mucormycosis and emphasizes the importance of its inclusion in the national notifiable communicable diseases priority list as well as the importance of enhancing diagnostic capacities to detect and improve patient outcomes.