Sumary of High single-dose efficacy of Pfizer vaccine against SARS-CoV-2 in older adults:
- In British Columbia (BC), Canada, vaccination against coronavirus disease 2019 (COVID-19) began with the Pfizer/Moderna mRNA (messenger ribonucleic acid) vaccines began with nursing home residents and frontline healthcare workers..
- New research by scientists in Canada suggests that these are known to have a high protective efficacy of 92-93% after a single dose, but this data comes from younger and healthy adults, for the most part..
- Background Since vaccine stocks are in short supply, many countries resorted to lengthening the interval between doses to increase single-dose coverage, thus protecting more people in a shorter time..
- This has made it difficult to differentiate direct and indirect vaccine effects, as well as the effect of the first dose as compared to that of both doses..
- Those who had positive virus tests by reverse transcriptase-polymerase chain reaction (RT-PCR) on specimens between weeks 14-17 from the start of the pandemic in BC were included..
- Community testing based on symptoms was used to identify real-life vaccine efficacy against all variants, including VOCs, after one dose of an mRNA vaccine..
- Related Stories Vaccine coverage (prime dose) among both cases and controls reached 85% and 90%, by week 14, 85% with the Pfizer vaccine..
- Vaccination associated with 65% fall in cases The findings show that vaccine efficacy (VE) was insignificant until two weeks after vaccination, increasing over the next week to 43% at 14-20 days….