It has long been established that Covid-19 vaccines reduce the risk of serious illness and hospitalization. But until recently, there was a question mark over reducing the transmission of the virus.
It is also an important question about what public health policy is built. The United Kingdom, for example, has commissioned faxes for all social care staff.
And in Italy, from October 15, workers will have to submit to the employer proof of vaccination, a negative covid test or recovery from a recent infection.
Anyone who cannot do this risks being suspended from work without a job. Other countries are taking similar measures.
But do vaccines actually limit the spread of the virus? A comprehensive study conducted by a team at Oxford University and specific analysis of the Delta variant showed that both Pfizer and AstraZeneca vaccines reduce the transmission of the disease.
The study looked at nearly 150,000 contacts that were followed from nearly 100,000 initial Covid cases.
The first positive cases contained a mixture of vaccinated and non-vaccinated individuals, and the aim was not only to see which groups were most likely to transmit the virus, but also which of the Pfizer and AstraZeneca vaccines were most effective in reducing transmission.
The findings showed that both vaccines reduced transmission, but that the Pfizer vaccine was the most effective in this regard.
As in previous studies, this Oxford study found that vaccinated and non-vaccinated groups had similar levels of the virus in their bodies, but those who were vaccinated were less likely to pass it on to others, suggesting that they spread the virus faster. could eliminate ..
There is a problem
The study found that the protection offered by vaccines against Covid-19 transmission decreases over time.
Three months after receiving the AstraZeneca injection, those who had discovered infections had spread the Delta variant just as well as those who had not been vaccinated. While the protection against transmission was reduced in people who received the Pfizer vaccine, there was still an advantage compared to people who were not vaccinated.
This sounds scary, Al Jazeera points out, but it’s important to note that vaccinated people have stronger immune systems and can get rid of the disease faster than non-vaccinated people.