Background Crimean-Congo hemorrhagic fever (CCHF) is a serious disease with a high fatality rate reported in many countries. The first case of CCHF in Oman was detected in 1995 and serosurveys have suggested widespread infection of humans and livestock throughout the country. Methodology Cases of CCHF reported to the Ministry of Health (MoH) of Oman between 1995 and 2017 were retrospectively reviewed. Diagnosis was confirmed by serology and/or molecular tests in Oman. Stored RNA from recent cases was studied by sequencing the complete open reading frame (ORF) of the viral S segment at Public Health England, enabling phylogenetic comparisons to be made with other S segments of strains obtained from the region. Findings Of 88 cases of CCHF, 4 were sporadic in 1995 and 1996, then none were detected until 2011. From 2011–2017, incidence has steadily increased and 19 (23.8%) of 80 cases clustered around Eid Al Adha. The median (range) age was 33 (15–68) years and 79 (90%) were male. The major risk for infection was contact with animals and/or butchering in 73/88 (83%) and only one case was related to tick bites alone. Severe cases were over-represented: 64 (72.7%) had a platelet count < 50 x 10 9 /L and 32 (36.4%) died. There was no intrafamilial spread or healthcare-associated infection. The viral S segments from 11 patients presenting in 2013 and 2014 were all grouped in Asia 1 (IV) lineage. Conclusions CCHF is well-established throughout Oman, with a single strain of virus present for at least 20 years. Most patients are men involved in animal husbandry and butchery. The high mortality suggests that there is substantial under-diagnosis of milder cases. Preventive measures have been introduced to reduce risks of transmission to animal handlers and butchers and to maintain safety in healthcare settings.

Objective To assess SARS-COV-2 seroprevalence in Oman and longitudinal changes in antibody levels over time within the first 11 months of the COVID-19 pandemic. Methods This nationwide cross-sectional study was conducted as a four-cycle serosurvey using a multistage stratified sampling method from July–November 2020. A questionnaire was used and included demographics, history of acute respiratory infection and list of symptoms, COVID-19 contact, previous diagnosis or admission, travel history, and risk factors. Results In total, 17,457 participants were surveyed. Thirty percent were female, and 66.3% Omani. There was significant increase in seroprevalence throughout the study cycles, starting from [5.5 (4.8–6.2)] for the first cycle and ending with [22 (19.6–24.6)] for the forth cycle. There was no difference in seroprevalence between genders, but significant differences between age groups. There was a transition of seroprevalence from being higher in non-Omanis in cycle one, [9.1 (7.6–10.9)] to Omanis [3.2 (2.6–3.9)] to being higher in Omanis [24.3 (21.0–27.9)] to non-Omanis [16.8 (14.9–18.9)] in cycle four. There was remarkable variation in seroprevalence of COVID-19 according to governorate. Close contacts of people with COVID-19 had a 96% higher risk of having the disease, (adjusted odds ratio [AOR]=1.96, 95% confidence interval [CI] 1.64–2.34); laborers have 58% higher risk of infection compared to office workers (AOR=1.58, 95% CI; 1.04–2.35). Conclusion The study showed a wide variation of SARS-CoV-2 dissemination between governorates in Oman, with higher seroprevalence estimates in migrants in the first two cycles. Prevalence estimates remain low and are insufficient to provide herd immunity.

Travel-associated infections account for about 8% of notifiable infections in Oman and have low mortality rate. However, some travel-associated infections are considered as a threat to polio eradication and measles elimination programs. Furthermore, some can cause outbreaks that can overwhelm the healthcare system.

Methods: Population-based data on all diagnosed people living with HIV reported to the National AIDS Programme in 1984-2018 were used. Results: As of December 31, 2018, the estimated number of people living with HIV in Oman was 3030; 1532 (50.6%) were aware of their infection. Of the diagnosed patients, 95.9% were linked to care, 85.8% were retained in care, and 84.3% were on ART. The proportions of patients with viral suppression out of all people with HIV, the diagnosed persons, and those on ART were 37.3%, 73.7%, and 87.5%, respectively. The proportion of patients linked to care increased from 72.6% in 2015 to 95.6% in 2018 (p < 0.001). Only 57% (947/1661) were retained in care in 2015, which increased to 76.9% (1193/1552) in 2017 and 85.8% (1314/ 1532) in 2018 (p < 0.001). Viral suppression increased from 75.7% (672/888) in 2015 to 84.5% (859/1017) in 2016 and 87.5% (1129/1291) in 2018 (p < 0.001). Conclusions: A sustained improvement in linkage to care, retention in care, ART coverage, and viral suppression was observed amongst people living with HIV in Oman in 2015-2018.

Several countries in the Middle East and around 22 countries worldwide have reported cases of human infection with the Middle East respiratory syndrome coronavirus (MERS-CoV). The exceptionally high fatality rate resulting from MERS-CoV infection in conjunction with the paucity of knowledge about this emerging virus has led to major public and international concern. Within the framework of the national acute respiratory illness surveillance, the Ministry of Health in the Sultanate of Oman has announced two confirmed cases of MERS-CoV to date. The aim of this report is to describe the epidemiological aspects of these two cases and to highlight the importance of public health preparedness and response. The absence of secondary cases among contacts of the reported cases can be seen as evidence of the effectiveness of infection prevention and control precautions as an important pillar of the national preparedness and response plan applied in the health care institutions in Oman.

Background: 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. Methods: 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 wholegenome 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. Findings: 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. Interpretation: 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.

To determine the seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in healthcare workers (HCWs) based on risk of exposure to COVID-19 patients. Method: This was a SARS-CoV-2 seroprevalence cross-sectional study in risk-stratified HCWs randomly selected from three main district hospitals in Oman. Results: 1078 HCWs were included, with an overall SARS-CoV-2 seroprevalence of 21%. The seropositivity rates in low-, variable-, and high-risk groups were 29%, 18%, and 17%, respectively (p-value < 0.001). The study found higher positivity in males (crude odds ratio [COR] 1.71, 95% confidence interval [CI] 1.28-2.3), and workers residing in high-prevalence areas (COR 2.09, 95% CI 1.42-3.07). Compared with doctors, workers from supporting services, administration staff, and nurses were more likely to test positive for SARS-CoV-2 antibodies (COR 9.81, 2.37,; 2.08 95% CI 1.14-3.81). The overall rate of previously undetected infection was 12%, with higher values in low-risk HCWs. High district prevalence was a driving factor for seropositivity in the low-risk group (adjusted odds ratio [AOR] 2.36, 95% CI 1.0-5.59). Conclusion: Low-risk supporting services workers can drive SARS-CoV-2 transmission in hospitals. More attention and innovation within this area will enhance the safety of health care during epidemics/ pandemics.

Achieving the UNAIDS target of 90% of HIV patients on treatment having VL suppression by 2020 is feasible in Oman.