Quote:
Originally Posted by mrmistoffelees
SOURCE:
https://www.forbes.com/sites/roberth...tudy-suggests/
A full course of the Pfizer-BioNTech vaccine was just 39% effective at preventing infections and 41% effective at preventing symptomatic infections caused by the Delta Covid-19 variant, according to Israel’s health ministry, down from early estimates of 64% two weeks ago.
The figures, based on data from an unspecified number of people between June 20 and July 17, are significantly lower than previous estimates of the vaccine’s efficacy against other variants, which initial clinical trials found to be 95%.
The Israel findings also conflict with several other studies assessing the vaccine’s performance against the Delta variant, which indicated only slightly diminished degrees of protection against infection and mild illness (between 80% and 90%), including peer reviewed research from Public Health England published Wednesday.
The vaccine still provides very high levels of protection against hospitalization (92%) and severe illness (91%) caused by the Delta variant, the ministry said.
In a statement, Pfizer and BioNTech noted that while real-world data from Israel show vaccine efficacy in preventing infection and symptomatic disease to decline six months post-vaccination, “efficacy in preventing serious illnesses remains high.” |
An interesting set of results from Israel. A big potential difference between the patients in the Israeli study and those surveyed by PHE is that in Israel the entire population has been jabbed with Pfizer, but on the recommended 21 day dose interval. In England, generally only vulnerable groups (elderly and others with urgent need) received Pfizer, until under 40s started getting vaccinated within the last couple of months. Additionally, in England the second dose was given on a 12 week interval (those who have had Pfizer more recently have had an 8 week interval).
I’m sure further research will be done to see what role the different demographics and dosage intervals might have played here, however to me this looks like tantalising evidence that the extended interval between doses may lead to a marked imporovement in vaccine performance.