Biostatistics, King Abdullah International Medical Research Center (KAIMRC); King Saud Bin Abdulaziz University for Health Sciences, Riyadh, Ar Riyāḑ, Saudi Arabia
Mr. Omar S. Aldibasi
Biostatistics, King Abdullah International Medical Research Center (KAIMRC); King Saud Bin Abdulaziz University for Health Sciences, Riyadh, Ar Riyāḑ, Saudi Arabia
To evaluate whether favipiravir reduces the time to viral clearance as documented by negative RT-PCR results for severe acute respiratory syndrome coronavirus 2 in mild cases of coronavirus disease 2019 (COVID-19) compared to placebo. In this randomized, double-blinded, multicentre, and placebo-controlled trial, adults with PCR-confirmed mild COVID-19 were recruited in an outpatient setting at seven medical facilities across Saudi Arabia. Participants were randomized in a 1:1 ratio to receive either favipiravir 1800 mg by mouth twice daily on day 1 followed by 800 mg twice daily (n = 112) or a matching placebo (n = 119) for a total of 5 to 7 days. The primary outcome was the effect of favipiravir on reducing the time to viral clearance (by PCR test) within 15 days of starting the treatment compared to the placebo group. The trial included the following secondary outcomes: symptom resolution, hospitalization, intensive care unit admissions, adverse events, and 28-day mortality. Two hundred thirty-one patients were randomized and began the study (median age, 37 years; interquartile range (IQR): 32–44 years; 155 [67%] male), and 112 (48.5%) were assigned to the treatment group and 119 (51.5%) into the placebo group. The data and safety monitoring board recommended stopping enrolment because of futility at the interim analysis. The median time to viral clearance was 10 days (IQR: 6–12 days) in the favipiravir group and 8 days (IQR: 6–12 days) in the placebo group, with a hazard ratio of 0.87 for the favipiravir group (95% CI 0.571–1.326; p = 0.51). The median time to clinical recovery was 7 days (IQR: 4–11 days) in the favipiravir group and 7 days (IQR: 5–10 days) in the placebo group. There was no difference between the two groups in the secondary outcome of hospital admission. There were no drug-related severe adverse events. In this clinical trial, favipiravir therapy in mild COVID-19 patients did not reduce the time to viral clearance within 15 days of starting the treatment.
MERS-CoV seronegative and seropositive camels received a single intramuscular dose of ChAdOx1 MERS, a replication-deficient adenoviral vectored vaccine expressing MERS-CoV spike protein, with further groups receiving control vaccinations. Infectious camels with active naturally acquired MERS-CoV infection, were co-housed with the vaccinated camels at a ratio of 1:2 (infected:vaccinated); nasal discharge and virus titres were monitored for 14 days. Overall, the vaccination reduced virus shedding and nasal discharge (p = 0.0059 and p = 0.0274, respectively). Antibody responses in seropositive camels were enhancedby the vaccine; these camels had a higher average age than seronegative. Older seronegative camels responded more strongly to vaccination than younger animals; and neutralising antibodies were detected in nasal swabs. Further work is required to optimise vaccine regimens for younger seronegative camels.
24 February 2023 in The Journal of Prosthetic Dentistry
The scanning strategy used when making complete arch digital scans affects the accuracy of the scan, and the accuracy of the strategy may be influenced by the scanner used. However, these effects have not been investigated thoroughly with complete arch edentulous scanning. The purpose of this in vitro study was to determine the effect of scanning strategies and the scanned arch on the accuracy of complete arch edentulous scans using 2 intraoral scanner (IOS) systems. Two IOSs were used (TRIOS 4 and Emerald S) to scan maxillary and mandibular typodonts using 6 scanning strategies (test scans), and conventional impressions of both arches were also made. By using a metrology software program, test scans were superimposed onto a reference scan, and the root mean square (RMS) of the absolute deviation values was calculated to express trueness. The sample with the best trueness was used as reference onto which the remaining samples from the same group were superimposed, and the RMS of the absolute deviation values was calculated to express precision. Statistical modeling was applied using the fixed effects models (α=.05). The main effects of scanner and strategy significantly impacted the trueness RMS values (P<.001), with significant interactions between them (P=.012). The main effects of scanner, strategy, and arch significantly impacted the precision of RMS values (P=.004), (P=.033), and (P=.023). Conventional impressions and the TRIOS 4 scanner had comparable accuracy, while the Emerald S scanner was inferior to both. P-O-B had the highest overall accuracy and strategy ZZ had the worst. Better precision was found with the maxillary arch. The scanner type and scanning strategy significantly impacted the accuracy of the digital scans of completely edentulous arches, with a significant interaction between scanner and strategy. The arch being scanned had a significant effect on scan precision but not on scan trueness.
1 July 2021 in Journal of Infection and Public Health
Estimated seroprevalence of Coronavirus Infectious Disease 2019 (COVID-19), caused by the Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) is a critical evidence for a better evaluation of the virus spread and monitoring the progress of COVID-19 pandemic in a population. In the Kingdom of Saudi Arabia (KSA), SARS-CoV-2 seroprevalence has been reported in specific regions, but an extensive nationwide study has not been reported. Here, we report a nationwide study to determine the prevalence of SARS-CoV-2 in the population of KSA during the pandemic, using serum samples from healthy blood donors, non-COVID patients and healthcare workers (HCWs) in six different regions of the kingdom, with addition samples from COVID-19 patients. A total of 11,703 serum samples were collected from different regions of the KSA including; 5395 samples from residual healthy blood donors (D); 5877 samples from non-COVID patients collected through residual sera at clinical biochemistry labs from non-COVID patients (P); and 400 samples from consented HCWs. To determine the seroprevalence of SARS-CoV-2, all serum samples, in addition to positive control sera from RT-PCR confirmed COVID-19 patients, were subjected to in-house ELISA with a sample pooling strategy, which was further validated by testing individual samples that make up some of the pools, with a statistical estimation method to report seroprevalence estimates. Overall (combining D and P groups) seroprevalence estimate was around 11% in Saudi Arabia; and was 5.1% (Riyadh), 1.5% (Jazan), 18.4% (Qassim), 20.8% (Hail), 14.7% (ER; Alahsa), and 18.8% in Makkah. Makkah samples were only D group and had a rate of 24.4% and 12.8% in the cities of Makkah and Jeddah, respectively. The seroprevalence in Saudi Arabia across the sampled areas would be 12 times the reported COVID-19 infection rate. Among HCWs, 7.5% (4.95–10.16 CI 95%) had reactive antibodies to SARS-CoV-2 without reporting any previously confirmed infection. This was higher in HCWs with hypertension. The study also presents the demographics and prevalence of co-morbidities in HCWs and subset of non-COVID-19 population. Our study estimates the overall national serological prevalence of COVID-19 in Saudi Arabia to be 11%, with an apparent disparity between regions. This indicates the prevalence of asymptomatic or mild unreported COVID-19 cases.
Combating the ongoing coronavirus disease 2019 (COVID-19) pandemic demands accurate, rapid, and point-of-care testing with fast results to triage cases for isolation and treatment. The current testing relies on reverse transcriptase PCR (RT-PCR), which is routinely performed in well-equipped laboratories by trained professionals at specific locations.
Objectives: To determine the incidence, trends, maternal and neonatal risk factors of severe intraventricular hemorrhage (IVH) among infants born 24–32 weeks and/or < 1500 g, and to evaluate the impact of changing of hospital policies and unit clinical practice on the IVH incidence. Study design: Retrospective chart review of preterm infants with a gestational age (GA) of 24–326 weeks and/or weight of < 1500 g born at King Abdulaziz Medical City–Riyadh (KAMC-R), Saudi Arabia, from 2016 to 2018. Multivariate logistic regression model was constructed to determine the probability of developing severe IVH and identify associations with maternal and neonatal risk factors. Results: Among 640 infants, the overall incidence of severe IVH was 6.4% (41 infants), and its rate decreased significantly, from 9.4% in 2016 to 4.5% and 5% in 2017 and 2018 (p = 0.044). Multivariate analysis revealed that caesarian section delivery decreased the risk of severe IVH in GA group 24–27 weeks (p = 0.045). Furthermore use of inotropes (p = 0.0004) and surfactant (p = 0.0003) increased the risk of severe IVH. Despite increasing use of inotropes (p = 0.024), surfactant therapy (p = 0.034), and need for delivery room intubation (p = 0.015), there was a significant reduction in the incidence of severe IVH following the change in unit clinical practice and hospital policy (p = 0.007). Conclusion: Cesarean section was associated with decreased all grades of IVH and severe IVH, while use of inotropes was associated with increased severe IVH. The changes in hospital and unit policy were correlated with decreased IVH during the study period.