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ABSTRACT Tuberculosis (TB) originating from expatriates that hail from high TB-burden countries is hypothesized to play a role in continued TB transmission in Oman. Here, we used whole-genome sequencing (WGS) to assess national TB transmission dynamics. The annual incidence per 100,000 population per year was calculated for nationals and expatriates. A convenience sample of Mycobacterium tuberculosis (MTB) isolates from 2018 to 2019 was sequenced and analyzed with publicly available TB sequences from Bangladesh, Tanzania, the Philippines, India, and Pakistan. Relatedness was assessed by generating core-genome single nucleotide polymorphism (SNP) distances. The incidence of TB was five cases per 100,000 persons in 2018 and seven cases per 100,000 persons in 2020 (R2 = 0.34, P = 0.60). Incidence among nationals was 3.9 per 100,000 persons in 2018 and 3.5 per 100,000 persons in 2020 (R2 = 0.20, P = 0.70), and incidence among expatriates was 7.2 per 100,000 persons in 2018 and 12.7 per 100,000 persons in 2020 (R2 = 0.74, P = 0.34). Sixty-eight local MTB isolates were sequenced and analyzed with 393 global isolates. Isolates belonged to nine distinct spoligotypes. Two isolates, originating from an expatriate and an Omani national, were grouped into a WGS-based cluster (SNP distance < 12), which was corroborated by an epidemiological investigation. Relatedness of local and global isolates (SNP distance < 100) was also seen. The relatedness between MTB strains in Oman and those in expatriate countries of origin can aid inform TB control policy. Our results provide evidence that WGS can complement epidemiological analysis to achieve the End TB strategy goal in Oman. IMPORTANCE Tuberculosis (TB) incidence in Oman remains above national program control targets. TB transmission originating from expatriates from high TB-burden countries has been hypothesized to play a role. We used whole-genome sequencing (WGS) to assess TB transmission dynamics between expatriates and Omani nationals to inform TB control efforts. Available Mycobacterium tuberculosis isolates from 2018 to 2019 underwent WGS and analysis with publicly available TB sequences from Bangladesh, the Philippines, India, and Pakistan to assess for genetic relatedness. Our analysis revealed evidence of previously unrecognized transmission between an expatriate and an Omani national, which was corroborated by epidemiological investigation. Analysis of local and global isolates revealed evidence of distant relatedness between local and global isolates. Our results provide evidence that WGS can complement classic public health surveillance to inform targeted interventions to achieve the End TB strategy goal in Oman.

Objectives: We sought to investigate the prevalence of HIV in pregnant women and the maternal, obstetrical, and neonatal outcomes over 13 years (2005–2017) at Sultan Qaboos University Hospital, a tertiary hospital in Muscat, Oman. Methods: Our study design was a retrospective descriptive cross-sectional study of HIV-positive women in the department of obstetrics and gynecology. We had an unlimited sample size due to the rarity of the disease. We aimed to include all pregnant Omani women who tested positive for HIV in their antenatal screening from 1 January 2005 to 31 December 2017. The patient records were reviewed using the hospital information system service. Results: There were a total of 13 688 women with 104 281 pregnancies over the study period. The prevalence of Omani pregnant women with HIV was 0.1% (1:1000) with 0.03% of seropositive pregnancies (3:10 000). Of these seropositive pregnancies, 78.6% were known HIV carriers, while 21.4% were newly diagnosed cases. The live birth rate was 90.3%, with 9.7% resulting in miscarriage. All the miscarriages were to known HIV-positive mothers who were managed in accordance with international guidelines. Of the live births, 10.7% were unknown HIV-positive mothers with a mean gestational age of 39.67 weeks and a mean birth weight of 3.2 kg. The rate of mother-to-child transmission (MTCT) of HIV in this group was 33.3%. In contrast, 89.3% of the live births to known HIV-positive mothers delivered neonates with a mean gestational age of 37.4 weeks and a mean birth weight of 2.6 kg with 0.0% MTCT. Modes of delivery, antepartum, intrapartum and postpartum complications as well as long-term neonatal outcomes were analyzed according to the status of the mother at first presentation. Conclusions: Strategies have been placed by programs in Oman to focus on the wellbeing of pregnant women and the protection of newborns against HIV infection. Strict implementations on preventing MTCT allowed preventing HIV in children possible. Antiretroviral therapy significantly reduces vertical transmission of HIV, in addition to abstinence of breastfeeding. More importantly, all HIV-positive pregnant women should follow the prevention of MTCT programs set out by the Ministry of Health.

Study aim. Effective Tuberculosis (TB) control measures in Oman have reduced the annual incidence of tuberculosis cases by 92% between 1981 and 2016. However, the current incidence remains above the program control target of Mycobacterium tuberculosis infection dynamics among nationals and foreigners over a period of 10 years. Methods. The study examined TB cases reported between 2009 and 2018 and examined the spatial heterogeneity of TB cases and the distribution of M. tuberculosis genotypes defined by spoligotypes and MIRU-VNTR among Omanis and foreigners. Results. A total of 484 spoligoprofiles were detected among the examined isolates (n = 1295). These include 943 (72.8%) clustered and 352 (27.2%) unique isolates. Diverse M. tuberculosis lineages exist in all provinces in Oman, with most lineages shared between Omanis and foreigners. The most frequent spoligotypes were found to belong to EAI (318, 30.9%), CAS (310, 30.1%), T (154, 14.9%), and Beijing (88, 8.5%) lineages. However, the frequencies of these lineages differed between Omanis and foreigners. Of the clustered strains, 192 MTB isolates were further analysed via MIRU-VNTR. Each isolate exhibited a unique MIRU-VNTR profile, indicative of absence of ongoing transmission. Conclusions. TB incidence exhibits spatial heterogeneity across Oman, with high levels of diversity of M. tuberculosis lineages among Omanis and foreigners and sub-lineages shared between the two groups. However, MIRU-VNTR analysis ruled out ongoing transmission.