A common virus that blocks the replication of the SARS-CoV-2 virus and reduces COVID-19 disease severity.
The virus that causes the common cold has the ability to give people some protection against coronavirus infection.
Rhinovirus is a mild viral infection responsible for the common cold in humans.
According to a new study, the virus can stimulate an innate immune response against SARS-CoV-2, stopping the virus from replicating in the respiratory tract.
An innate or natural immunity is the first line of defence against any infection invading our body.
Respiratory viruses such as rhinovirus often infect cells in the respiratory tract whereas other type of viruses can only infect some of the cell types in the human body.
The interaction between different viruses may change the epidemiology of respiratory infections so as the prevalence of rhinoviruses increases, the number of new COVID cases will go down.
Rhinoviruses are responsible for more than 50 percent of respiratory tract infections, therefore the rhinoviruses’ interactions with other respiratory viruses influences the severity and type of infections in people.
This virus-to-virus interaction may also influence patterns of infection and how they circulate and infect different people.
As well as the respiratory tract, virus-to-virus interactions can happen in multi-virus environments such as the gastrointestinal tract.
For this study, samples of human respiratory cells were infected with SARS-CoV-2 in the lab.
The team created a similar environment to the human body where infections occur.
Then they examined the replication SARS-CoV-2 in these cells in the absence or presence of rhinovirus.
Professor Pablo Murcia, the study’s co-author, said:
“Our research shows that human rhinovirus triggers an innate immune response in human respiratory epithelial cells which blocks the replication of the COVID-19 virus, SARS-CoV-2.
This means that the immune response caused by mild, common cold virus infections, could provide some level of transient protection against SARS-CoV-2, potentially blocking transmission of SARS-CoV-2 and reducing the severity of COVID-19.
The next stage will be to study what is happening at the molecular level during these virus-virus interactions, to understand more about their impact on disease transmission.
We can then use this knowledge to our advantage, hopefully developing strategies and control measures for COVID-19 infections.
In the meantime, vaccination is our best method of protection against COVID-19.”
The study was published in The Journal of Infectious Diseases (Dee et al., 2021).
