Although it is not clear how long the acquired immunity can last, many research teams around the world are still actively looking for potential vaccines or other drugs to cope with the worldwide pandemic of covid-19. Before the advent of specific vaccines, people had to strictly follow guidelines such as washing hands frequently, wearing personal protective equipment (such as masks and goggles), and maintaining social alienation. However, a new study published recently reveals that some people have acquired immunity to the new coronavirus after the common cold.

this article, published in the journal Nature, introduces the results of studies on patients with covid-19 and uninfected control groups. The results show that specific T-cell immunity against sars-cov-2 has been detected in some people with common cold.

according to a similar study, if people have been exposed to other types of coronavirus that may cause common cold, they may also lead to certain immune responses, thus providing protection against sars-cov-2 infection.

even so, we can better cope with the pandemic of new coronavirus only if we have a lasting immune effect. This is also a major direction of current vaccine development, including attenuated vaccines and enhanced immune responses induced by other treated pathogens.

the available reference data indicate that it is difficult for humans to be immune to coronavirus for more than 12 months. A recent study has shown that even if T cells can take effect immediately after reinfection and kill the new coronavirus, antibodies are likely to disappear after three months.

Duke School of medicine, National University of Singapore, pointed out that four of the seven coronaviruses that can infect humans at present can cause common cold. The other three (SARS, mers, sars-cov-2) may lead to serious complications and even death.

However, in this new study, scientists found that previous contact with other coronaviruses can leave T cells with memories, thus producing an immune response to covid-19. By testing T cells from patients who had recovered, they found these types of white blood cells.

in addition, the team found that 17 years ago, SARS patients still have specific T cells for SARS, which may provide immunity against new coronavirus.

more interestingly, the researchers tested people who had never been exposed to sars-cov-2 and found that healthy subjects who were not infected with the new coronavirus may also have T cells resistant to the virus.

Professor Antonio bertoletti said that they found specific T cells for sars-cov-2 in 50% of healthy subjects, which may be the traces of cross immune response left by participants’ previous exposure to other coronaviruses.

these pathogens may cause the common cold, or some unknown animal type coronavirus. Based on this new study, it may explain why people can better control covid-19 infection.

at present, the research team is looking for other covid-19 immune lucky children to understand the duration of T cells in their bodies. Interestingly, some candidate vaccines also induce dual defense (neutralizing antibodies + T cells).