How effective are Moderna and Pfizer vaccines against the Delta type Coronavirus?
MRNA cod vaccines developed by Moderna and Pfizer / BioNTech were initially up to 91% effective in controlling the disease, but their effectiveness with Corona type delta was reduced to 66%.
This is according to a new study released by the US Centers for Disease Control and Prevention .
The study found that the effectiveness of vaccines declined in the United States when the highly contagious type of corona, Delta, became dominant.
According to research, the lack of effectiveness of vaccines indicates that this type of corona is highly contagious, but at the same time it also shows how important vaccination is to prevent the severity of the disease, hospitalization and death.
“Although we have seen a decrease in the effectiveness of vaccines against the corona-type delta, they still reduce the risk of contracting the disease by two-thirds,” the researchers said.
A total of 4,217 workers from medical staff and other key institutions were included in the study and tested weekly.
Of these, 83% or 3483 had been vaccinated, 65% had been vaccinated with Pfizer, 33% with Moderna and 2% with the Johnson & Johnson vaccine.
According to research, from December 2020 to April 2021, the effectiveness of vaccines against the disease was 90%.
Between April and August, the corona-type delta spread to the United States and the effectiveness of vaccines began to decline.
During the study, 24 out of 2353 people who completed the vaccination were diagnosed with code and 75% had symptoms.
But the study did not say what the symptoms were or how severe they were.
According to researchers, vaccines are still very powerful, but we should continue to use face masks for some time to come.
Experts plan to continue research and will now compare different vaccines to see what kind of symptoms appear in people who use the vaccine and those who do not.
The results come as the United States has decided to give additional doses to vaccinators from September.
The decision is aimed at reducing the risk of disease by increasing the effectiveness of vaccines over time