Transmission dynamics and mutational prevalence of the novel SARS‐CoV‐2 Omicron Variant of Concern

The novel Severe acute respiratory syndrome coronavirus‐2 (SARS‐CoV‐2) variant, Omicron (PANGO lineage B.1.1.529) is being reported from all around the world. The WHO has categorized Omicron as a Variant of Concern (VOC) considering its higher transmissibility and infectivity, vaccine breakthrough cases. As of January 6, 2022, Omicron has been reported in at least 149 countries. Therefore, this study was planned to investigate the transmission dynamics and mutational prevalence of the novel SARS‐CoV‐2 Omicron variant. The transmission dynamics and Omicron SARS‐CoV‐2 divergence was studied using GISAID and Nextstrain which provides information about the genetic sequences, epidemiological, geographical, and species‐specific data of human, avian, and animal viruses. Further, the mutation prevalence in spike glycoprotein of Omicron was studied, and the frequency of the crucial mutations was compared with the other prevalent VOCs. The transmission dynamics suggest that the Omicron was first identified in South Africa and then it was reported in the United Kingdom followed by the United States and Australia. Further, our phylogenetic analysis suggests that Omicron (BA.1) was clustered distinctly from the other VOCs. In the Spike glycoprotein, the Omicron (B.1.1.529) demonstrates critical 32 amino acid changes. This study may help us to understand mutational hotspots, transmission dynamics, phylogenetic divergence, effect on testing and immunity, which shall promote the progress of the clinical application and basic research.

First report showing the transmissibility of the novel sSevere acute respiratory syndrome coronavirus‐2 (SARS‐CoV‐2) Omicron (B.1.1.529) Variant of Concern.

Transmission dynamics analysis suggests that Omicron is more transmissible than other Variant of Concerns (VOCs).

Omicron (BA.1) is clustered distinctly from the other VOCs in a monophyletic clade.

The K417N, N440K, and G446S are the less prevalent mutations identified in the RBD of the Omicron SARS‐CoV‐2.

Clinical manifestations of SARS-CoV-2 infection in neonates and the probability of maternal transmission

AIM

This study aimed to measure the incidence of SARS-CoV-2 infection in neonates from infected mothers and to screen disease severity in neonates.

METHODS

We conducted a population-based cohort study of neonates from SARS-CoV-2-positive mothers, enrolling mothers who tested positive for SARS-CoV-2 and their neonates. Eleven infants <25 days old presenting with SARS-CoV-2 infection were also included in the study. We recorded clinical symptoms of SARS-CoV-2-positive mothers and their neonates.

RESULTS

One of 126 babies born to SARS-CoV-2-infected mothers was found to be positive (0.79%). The referred positive neonates were either asymptomatic or suffered from symptoms ranging from mild respiratory distress to pneumonia. Most SARS-CoV-2-positive neonates showed neutropenia and lymphocytosis. Most of the SARS-CoV-2-infected mothers (n = 126) were either asymptomatic (46, 36.5%) or showed mild respiratory distress (66, 52.4%). However, pneumonia and severe respiratory distress were reported in 14 (11.1%) of the SARS-CoV-2-infected mothers. There were no deaths of either SARS-CoV-2-infected mothers or neonates.

CONCLUSION

We conclude that mothers transmitted infection to their neonates at a very low rate. Disease in neonates is usually mild, although some babies have severe disease. SARS-CoV-2 infection in late pregnancy usually leads to mild maternal disease, but severe disease is reported in approximately one-tenth of the infected women.

Tracing the origin of Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2): A systematic review and narrative synthesis

The aim of the study was to trace and understand the origin of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) through various available literatures and accessible databases. Although the world enters the third year of the coronavirus disease 2019 pandemic, health and socioeconomic impacts continue to mount, the origin and mechanisms of spill-over of the SARS-CoV-2 into humans remain elusive. Therefore, a systematic review of the literature was performed that showcased the integrated information obtained through manual searches, digital databases (PubMed, CINAHL, and MEDLINE) searches, and searches from legitimate publications (1966-2022), followed by meta-analysis. Our systematic analysis data proposed three postulated hypotheses concerning the origin of the SARS-CoV-2, which include zoonotic origin (Z), laboratory origin (L), and obscure origin (O). Despite the fact that the zoonotic origin for SARS-CoV-2 has not been conclusively identified to date, our data suggest a zoonotic origin, in contrast to some alternative concepts, including the probability of a laboratory incident or leak. Our data exhibit that zoonotic origin (Z) has higher evidence-based support as compared to laboratory origin (L). Importantly, based on all the studies included, we generated the forest plot with 95% confidence intervals (CIs) of the risk ratio estimates. Our meta-analysis further supports the zoonotic origin of SARS/SARS-CoV-2 in the included studies.