High levels of T cells from coronaviruses that cause the common cold can provide protection against COVID-19, a recent study has found.

It examined levels of cross-reactive T cells produced by earlier common colds in 52 household contacts of positive COVID-19 cases.

The researchers found that the 26 who did not develop infection had notably higher levels of those T cells than people who did get infected.

The study did not say how long protection from the T cells would last.

Kundu said, "We found that high levels of pre-existing T cells, created by the body when infected with other human coronaviruses like the common cold, can protect against COVID-19 infection.".

The team that wrote about the research said that the T cells targeted proteins inside the SARS-CoV-2 virus.

Current COVID-19 vaccines target the spike protein, a protein on the outside surface of the virus, which changes or mutates regularly.

These changes in the spike protein also reduce the effectiveness of vaccines against infections that show physical signs