Real-world evidence from Covid immunization programs in England and Scotland shows that one dose of the vaccine provides high protection against serious illness and hospitalization - and also protects against mild illness, with no symptoms in young people.
The first real data from mass vaccination programs are promising, and although the results do not include evidence that completely prevents transmission, there is evidence that they are preventing some people from becoming infected, which would slow the spread of the coronavirus.
Three studies reached similar positive conclusions about the protection provided by vaccines - one in Scotland and two in England.
In the UK, a study in healthcare workers under the age of 65 found that one dose of the Pfizer / BioNTech vaccine reduced the risk of catching the virus by 70% - and 85% after the second dose. Health care workers were all tested for the virus every two weeks, so the study considered asymptomatic infections as well as those who had symptoms.
Public Health in England also published the results of routine testing over the age of 80, who are at higher risk of becoming seriously ill and dying from Covid. This revealed that 3 weeks after the first dose, the Pfizer / BioNTech vaccine was 57% effective against symptomatic disease, whether mild or severe. Although not many people have had a second dose, evidence has suggested that efficacy increased to 85% in those who did.
The data also show that people who are vaccinated and who get the infection again are much better protected from serious illness, hospitalization and death.
The scientists, whose work has not been reviewed by colleagues, said the results from the two vaccines should not be compared. There was more data on people who received the Pfizer vaccine, while the AstraZeneca vaccine was administered mainly to older people.
Source: Guardian