Understanding the transmission of SARS-CoV-2 is complicated by the large numbers of presymptomatic, asymptomatic, and mildly symptomatic (PAMS) patients. The reproductive number, R0, is a measure of population-level dynamics, but it cannot provide information on infectiousness of different groups such as PAMS subjects; when peak infectiousness occurs; and the effect of intrinsic properties of the …
In the two previous installments (one, two) of what has now become my praise of T cells, I explained that the SARS-CoV-2 protein sequences recognized by T cells do not change, likely explaining why vaccines prevent serious disease and death caused by any variant. Today I will explain that virus-specific T cells appear a week …
It is slowly becoming clear that the immunity induced by SARS-CoV-2 vaccination is of overall better quality than that induced by COVID-19.
All human viruses, including SARS-CoV-2, arose from spillovers from other animals. Results of a recent study of bat samples collected in a small region of Yunnan Province, China revealed additional close relatives of SARS-CoV-2 and SARS-CoV. After the identification of SARS-CoV-2 in early 2020, wildlife sampling and retrospective genome sequencing revealed highly related viruses in …
The emergence and spread throughout Europe of a SARS-CoV-2 variant, 20E (EU1) in the summer of 2020 illustrates how a virus may become dominant not by increased transmissibility but through travel and lack of effective containment and screening. The SARS-CoV-2 variant 20E (EU1) emerged in Spain in the summer of 2020 and spread to multiple …
Holiday travel explains spread of a SARS-CoV-2 variant Read More »
T cells are the other arm of the adaptive immune response (in addition to B cells) that are essential for clearing virus infections. Most studies of immunity to SARS-CoV-2 infection have focused on antibodies and their ability to neutralize virus infection. The observation that variants of concern are less effectively neutralized by antibodies against ancestral …
