DR DOUG QUARRY
In this edition:
PART 1: Mutations and Variants
1.1 Coronavirus mutations
1.2 The most significant mutations
1.3 Summary of the major variants
1.4 Where B.1.1.7 variant, first identified in the UK, has been found
1.5 Where B.1.351 variant, first identified in the South Africa, has been found
1.6 Where P.1 variant, first identified in Brazil, has been found
PART 2: Variant News
2.1 South Africa suspends use of AstraZeneca’s COVID-19 vaccine
2.2 South Africa to start COVID-19 vaccinations with J&J doses
2.3 Israel: 94% drop in symptomatic COVID cases after two Pfizer shots
2.4 Three Israelis who have recovered from COVID have been reinfected with B.1.351 variant
2.5 In vitro immune evasion of the B.1.351 variant (South Africa) to both the mRNA vaccines
2.7 Possible new reason for B.1.1.7 increased infectiousness
2.7 Keeping up-to-date with variants
PART 1: MUTATIONS AND VARIANTS
1.1 Coronavirus mutations
- Each coronavirus contains nearly 30,000 “letters” of RNA
- This allows the virus to infect cells to make new viruses
- An infected cell occasionally makes tiny copying errors (mutations) when creating new coronaviruses
- Scientists can track mutations
A VARIANT is a group of coronaviruses that share the same inherited set of distinctive mutations.
1.2 The most significant mutations
- Thousands of mutations of SARS-CoV-2 have been found
- At present, the B.1.1.7, B.1.35, and P1 are the three most important mutations. This is due to their ability to:
o Increase transmissibility, and/or
o Avoid some type of antibodies (immune escape)
1.3 Summary of the major variants
- N501Y mutation found in all three variants
- E484K mutation found in B.1.351 (SA) and P1 (Brazil)
1.4 Where B.1.1.7 variant (first identified in the UK) has been found
1.5 Where B.1.351 variant (first identified in the South Africa) has been found
1.6 Where P.1 variant (first identified in Brazil) has been found
PART 2: VARIANT NEWS
2.1 South Africa suspends use of AstraZeneca’s COVID-19 vaccine
Sciencemag reports that a South African trial of the AstraZeneca vaccine, conducted in about 2,000 people, found a low efficacy (25%) against mild and moderate disease. However, scientists are hopeful it might still prevent severe disease and death – the most important job for any COVID-19 vaccine. That was impossible to tell from this placebo-controlled trial because it was small and recruited relatively healthy, young people – their average age was only 31. None of the subjects in either arm of the study developed severe disease or required hospitalisation.
Due to the low efficacy against mild and moderate COVID disease, the South African Government has suspended the use of the AstraZeneca vaccine.
2.2 South Africa to start COVID-19 vaccinations with J&J doses
Reuters reports that South Africa will start its immunisation campaign with Johnson & Johnson’s COVID-19 vaccine. The country had planned to start offering healthcare workers the AstraZeneca vaccine soon but put that plan on hold on Sunday. A government factsheet published on Monday said the J&J vaccine would be offered from mid-February.
2.3 Israel: 94% drop in symptomatic COVID cases after two Pfizer shots
Reuters reports that: “Israel’s largest healthcare provider has reported a 94% drop in symptomatic COVID-19 infections among 600,000 people who received two doses of the Pfizer’s vaccine in the country’s biggest study to date. “Health maintenance organization (HMO) Clalit, which covers more than half of all Israelis, said the same group was also 92% less likely to develop severe illness from the virus.”
2.4 Three Israelis who have recovered from COVID have been reinfected with B.1.351 variant
The Washington Post reports that Israel’s Health Ministry has reported that two more Israeli’s, who have recently recovered from Coronavirus, have been reinfected with “South African” B.1.351 coronavirus strain. The total of such cases is now three. The Health Ministry is investigating and has said that the cases came from a northern area, made up of Arab towns and villages, where the vaccination rollout has been slower than in the majority of the country.
2.5 In vitro immune evasion of the B.1.351 variant (Sth Africa) to both the mRNA vaccines
In detail: Laboratory tests studying the antibody neutralization have found:
· For Pfizer vaccine: neutralization of the B.1.351-spike virus was weaker by approximately 2/3rds
· For Moderna vaccine: study detected reductions by a factor of 6.4 against the B.1.351 variant
2.6 Possible new reason for B.1.1.7 increased infectiousness
A new study from Dash Harvard has found that B.1.1.7’s increased infectiousness is due to a prolonged acute infection with delayed clearance of the virus, rather than a higher viral load as previously thought.
2.7 Keeping up-to-date with variants
The News and Updates section of the New York Times Coronavirus Variant Tracker is an excellent source of updated news on variants.
From NYT 19 February 2021
**Eric Topol: Professor of Molecular Medicine at The Scripps Research Institute, and a senior consultant at the Division of Cardiovascular Diseases at Scripps Clinic in La Jolla, California. Editor-in-chief of Medscape and theheart.org.
