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 …
Recently isolated coronaviruses from humans in Haiti and Malaysia appear to have originated in pigs and dogs.
Eradication of poliomyelitis appears to be on track: types 2 and 3 polioviruses have been declared eradicated, and in the past 12 months there have been just 338 cases of type 1 polio in Afghanistan and Pakistan. But there have also been 491 cases of polio caused by the type 2 Sabin vaccine. The development …
A genetically stable attenuated poliovirus vaccine Read More »
During viral replication, defective genomes may arise that lack essential sequences. These so-called defective genomes cannot replicate unless they are in the same cell as a helper virus. Defective genomes play a role in modulating pathogenesis of respiratory syncytial virus in humans. Copy-back defective viral genomes (cbDVGs) of RSV arise when the viral RNA polymerase …
Defective genomes modulate respiratory syncytial virus pathogenesis Read More »
