Do COVID-19 vaccines prevent severe disease?

A team of Oxford University scientists has revealed important insights into how Covid-19 vaccines reduce cases of severe illness after vaccination.

Scientists conducted an extensive investigation into the human immune response to “Covid-19”, in both vaccinated and unvaccinated people.

The results of the study show a decrease in disease severity indicators in those who received the vaccine, which means that the harmful inflammatory reaction to “Covid” is less severe in them compared to people who did not receive the vaccine.

Study leader, Professor Daniel O'Connor, Head of Bioinformatics at the Oxford Vaccine Group (OVG), said: “These results confirm the effectiveness of vaccination and its pivotal role in reducing the harmful consequences associated with “Covid-19”, and also highlight the potential of the ChAdOx1 nCoV-19 vaccine. "Modifies harmful responses to SARS-CoV-2, thereby reducing disease severity."

He added, explaining: “The implications of these results are far-reaching, and provide essential evidence for future vaccine development and pandemic mitigation strategies.”

Professor Andrew Pollard, Professor of Infection and Immunity and Director of the OVG, said: “Better understanding how vaccines reduce the severity of infections caused by viruses like Covid-19 is a key part of our readiness to make vaccines effective.

The study used the latest technologies, including RNA sequencing (to determine the level of genes produced by blood cells), to achieve these results.

While the results are promising, the study acknowledges limitations, such as the focus on mild cases and sample size, highlighting the need for further research using advanced techniques to enhance accuracy.

The study was published in the journal Nature Communications.