#COVID research updates: Trial hints that Pfizer vaccine could curb COVID transmission
►https://www.nature.com/articles/d41586-020-00502-w
Le #vaccin Pfizer/BioNTech n’empêcherait pas seulement le développement de symptômes mais aussi l’infection elle-même, donc la #transmission du virus.
Large-scale trials of #COVID-19 vaccines have focused on assessing their ability to prevent disease, but researchers also want to know whether the vaccines can prevent people from getting infected, even if they show no symptoms. Susan Hopkins at Public Health England in London and her colleagues tracked the effectiveness of the vaccine made by Pfizer and BioNTech in 23,000 UK health-care workers who were already part of a long-term study of #SARS-CoV-2 immunity (V. J. Hall et al. Preprint at SSRN ▻https://doi.org/fw7v; 2021). Participants were tested regularly for SARS-CoV-2, regardless of their symptoms.
The vaccine was 70% effective at preventing both symptomatic and asymptomatic infections in the period beginning 3 weeks after the first dose; this grew to 85% shortly after a second dose of the RNA vaccine. This finding is the first evidence that Pfizer’s vaccine might block transmission, the researchers say. The study has not yet been peer reviewed.
Source:
Effectiveness of BNT162b2 mRNA Vaccine Against Infection and COVID-19 Vaccine Coverage in Healthcare Workers in England, Multicentre Prospective Cohort Study (the SIREN Study) by Victoria Jane Hall, Sarah Foulkes, Ayoub Saei, Nick Andrews, Blanche Oguti, Andre Charlett, Edgar Wellington, Julia Stowe, Natalie Gillson, Ana Atti, Jasmin Islam, Ioannis Karagiannis, Katie Munro, Jameel Khawam, The SIREN Study Group, Meera A. Chand, Colin Brown, Mary E. Ramsay, Jamie Lopez Bernal, Susan Hopkins :: SSRN
▻https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3790399
.... this cohort was vaccinated when the dominant variant in circulation was B1.1.7 and demonstrates effectiveness against this variant.
