12/04/2021

Coronavirus

We used computational studies to examine the Delta and Omicron variants in this work and found that the Omicron variant had a higher affinity for human ACE2 than the Delta variant due to a significant number of mutations in the SARS-CoV-2 receptor binding domain, indicating a higher potential for transmission. Based on docking studies, the Q493R, N501Y, S371L, S373P, S375F, Q498R, and T478K mutations contribute significantly to high binding affinity with human ACE2. In comparison to the Delta variant, both the entire spike protein and the RBD in Omicron include a high proportion of hydrophobic amino acids such as leucine and phenylalanine. These amino acids are located within the protein's core and are required for structural stability.

Despite compelling evidence that SARS-CoV-2 vaccines are highly effective in preventing COVID-19 infections, breakthrough cases have been emerging at an increasing rate. The shifting landscape of breakthrough COVID-19 cases is likely to involve multiple factors, including demonstrated waning of antibody response after full vaccination7, 8 and emergence of variant strains of SARS-CoV-2.

In the United States, a hunt for the variant began last week when South African researchers announced Omicron’s array of worrisome mutations. The search has intensified in recent days, with at least 12 states identifying cases. Researchers are combing through wastewater samples for any sign of the variant. Contact tracers are ramping up efforts in places where cases have emerged. And at sequencing labs like the one in Nebraska, a state where case rates are already high and hospitals are already strained, scientists have sped up the screening of samples from international travelers to see if Omicron has arrived.

We report detection of severe acute respiratory syndrome coronavirus 2 Omicron variant (B.1.1.529) in an asymptomatic, fully vaccinated traveler in a quarantine hotel in Hong Kong, China. The Omicron variant was also detected in a fully vaccinated traveler staying in a room across the corridor from the index patient, suggesting transmission despite strict quarantine precautions.

Cascade Screening

NCI released a funding opportunity to test a “traceback” strategy, where researchers are finding the women who were previously diagnosed with ovarian cancer, communicating with them (or with their family members if they have died), and offering genetic testing. Traceback is a unique approach to genetic testing because the idea is to work backwards and find previously diagnosed cases to test to improve the detection of families at risk. Three grants using different approaches for traceback testing were funded for 4 years; projects are expected to be completed in 2023. The overall goal is to evaluate the best way to communicate sensitive genetic information to ovarian cancer patients and their immediate family members. Challenges associated with privacy laws and ethical concerns, differences in cultural traditions, and medical literacy are taken into account.