Project description:Introduction and objectivesLiver injury in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant- and Omicron subvariant-infected patients is unknown at present, and the aim of this study is to summarize liver injury in these patients.Materials and methodsIn this study, 460 SARS-CoV-2-infected patients were enrolled. Five severe or critical patients were excluded, and 34 patients were also excluded because liver injury was not considered to be related to SARS-CoV-2 infection. Liver injury was compared between Omicron and non-Omicron variants- and between Omicron subvariant-infected patients; additionally, the clinical data related to liver injury were also analyzed.ResultsAmong the 421 patients enrolled for analysis, liver injury was detected in 76 (18.1%) patients, including 46 Omicron and 30 non-Omicron variant-infected patients. The ratios did not differ between Omicron and non-Omicron variant-, Omicron BA.1, BA.2 and BA.5 subvariant-infected patients (P>0.05). The majority of abnormal parameters of liver function tests were mildly elevated (1-3 × ULN), the most frequently elevated parameter of liver function test was γ-glutamyl transpeptidase (GGT, 9.5%, 40/421), and patients with cholangiocyte or biliary duct injury markers were higher than with hepatocellular injury markers. Multivariate analysis showed that age (>40 years old, OR=1.898, 95% CI=1.058-3.402, P=0.032), sex (male gender, OR=2.031, 95% CI=1.211-3.408, P=0.007), serum amyloid A (SAA) level (>10 mg/ml, OR=3.595, 95% CI=1.840-7.026, P<0.001) and vaccination status (No, OR=2.131, 95% CI=1.089-4.173, P=0.027) were independent factors related to liver injury.ConclusionsLiver injury does not differ between Omicron and non-Omicron variants or between Omicron subvariant-infected patients. The elevations of cholangiocyte or biliary duct injury biomarkers are dominant in SARS-CoV-2-infected patients.
Project description:BackgroundTaiwan was a coronavirus disease 2019 (COVID-19) outlier, with an extraordinarily long transmission-free record: 253 days without locally transmitted infections while the rest of the world battled wave after wave of infection. The appearance of the alpha variant in May 2021, closely followed by the delta variant, disrupted this transmission-free streak. However, despite low vaccination coverage (<1%), outbreaks were well-controlled.MethodsThis study analyzed the time to border closure and conducted one-sample t test to compare between Taiwan and Non-Taiwan countries prior to vaccine introduction. The study also collected case data to observe the dynamics of omicron transmission. Time-varying reproduction number,Rt, was calculated and was used to reflect infection impact at specified time points and model trends of future incidence.ResultsThe study analyzed and compare the time to border closure in Taiwan and non-Taiwan countries. The mean times to any border closure from the first domestic case within each country were -21 and 5.98 days, respectively (P < .0001). The Taiwanese government invested in quick and effective contact tracing with a precise quarantine strategy in lieu of a strict lockdown. Residents followed recommendations based on self-discipline and unity. The self-discipline in action is evidenced in Google mobility reports. The central and local governments worked together to enact non-pharmaceutical interventions (NPIs), including universal masking, social distancing, limited unnecessary gatherings, systematic contact tracing, and enhanced quarantine measures. The people cooperated actively with pandemic-prevention regulations, including vaccination and preventive NPIs.ConclusionsThis article describes four key factors underlying Taiwan's success in controlling COVID-19 transmission: quick responses; effective control measures with new technologies and rolling knowledge updates; unity and cooperation among Taiwanese government agencies, private companies and organizations, and individual citizens; and Taiwanese self-discipline.
Project description:We reconstructed the SARS-CoV-2 epidemic caused by Omicron variant in Puerto Rico by sampling genomes collected during October 2021-May 2022. Our study revealed that Omicron BA.1 emerged and replaced Delta as the predominant variant in December 2021. Increased transmission rates and a dynamic landscape of Omicron sublineage infections followed.
Project description:Since April 2022, waves of SARS-CoV-2 Omicron variant cases have surfaced in Taiwan and spread throughout the island. Using high-throughput sequencing of the SARS-CoV-2 genome, we analyzed 2,405 PCR-positive swab samples from 2,339 persons and identified the Omicron BA.2.3.7 variant as a major lineage within recent community outbreaks in Taiwan.
Project description:IntroductionIn November 2021, the SARS-CoV-2 Omicron variant of concern has emerged and is currently dominating the COVID-19 pandemic over the world. Omicron displays a number of mutations, particularly in the spike protein, leading to specific characteristics including a higher potential for transmission. Although Omicron has caused a significant number of deaths worldwide, it generally induces less severe clinical signs compared to earlier variants. As its impact on blood platelets remains unknown, we investigated platelet behavior in severe patients infected with Omicron in comparison to Delta.MethodsClinical and biological characteristics of severe COVID-19 patients infected with the Omicron (n=9) or Delta (n=11) variants were analyzed. Using complementary methods such as flow cytometry, confocal imaging and electron microscopy, we examined platelet activation, responsiveness and phenotype, presence of virus in platelets and induction of selective autophagy. We also explored the direct effect of spike proteins from the Omicron or Delta variants on healthy platelet signaling.ResultsSevere Omicron variant infection resulted in platelet activation and partial desensitization, presence of the virus in platelets and selective autophagy response. The intraplatelet processing of Omicron viral cargo was different from Delta as evidenced by the distribution of spike protein-positive structures near the plasma membrane and the colocalization of spike and Rab7. Moreover, spike proteins from the Omicron or Delta variants alone activated signaling pathways in healthy platelets including phosphorylation of AKT, p38MAPK, LIMK and SPL76 with different kinetics.DiscussionAlthough SARS-CoV-2 Omicron has different biological characteristics compared to prior variants, it leads to platelet activation and desensitization as previously observed with the Delta variant. Omicron is also found in platelets from severe patients where it induces selective autophagy, but the mechanisms of intraplatelet processing of Omicron cargo, as part of the innate response, differs from Delta, suggesting that mutations on spike protein modify virus to platelet interactions.