If someone leaves their car unlocked, they may face theft. Such an experience often makes them more cautious in the future. Similarly, a common cold infection may prepare the immune system. This preparation can help protect against future threats like COVID-19.
Researchers at National Jewish Health studied this connection. They found prior rhinovirus infection could cut COVID-19 risk nearly in half. This protection may help explain why children have milder COVID-19 symptoms. Children often face more colds than adults, boosting immune readiness.
What Key Findings Showed Colds Protect from COVID-19?
Researchers published their findings in the Journal of Infectious Diseases. They tested 10,493 nasal swabs from 1,156 U.S. children and adults. The study ran from May 2020 to February 2021. Samples were screened for 21 respiratory pathogens, including the common cold virus.
Scientists sequenced RNA from 147 swabs collected before COVID-19 infection. They also analyzed 391 swabs from 165 people before and during rhinovirus infection. Rhinovirus infection within the past 30 days lowered COVID-19 risk by 48%. This protection was greater with recent and symptomatic rhinovirus infections.
Among COVID-19 patients, recent rhinovirus infection reduced the viral load. The decrease was 9.6-fold, showing much less virus in the body. Lower viral load often leads to a milder illness. This effect was tied to higher antiviral gene expression in the airway.
The study linked 57 genes to lower SARS-CoV-2 viral load. Twenty-four of these genes have known antiviral defense roles. Rhinovirus infection triggered the expression of 22 of these genes. Children showed higher antiviral gene expression than adults.
Children were also more likely to have rhinovirus infections. Their risk was 2.2 times higher compared to adults. Frequent colds may help keep their antiviral defenses active. This may explain their milder COVID-19 outcomes.
What Methods Demonstrated Colds Protect Against COVID?
Participants self-collected nasal swabs every two weeks during the study. Samples were tested for SARS-CoV-2 using PCR tests. Rhinovirus appeared more often than SARS-CoV-2 for most of the study. HRV incidence was moderate in summer 2020 and rose in fall.
SARS-CoV-2 patterns differed from HRV during the same period. Samples were screened for 18 respiratory viruses every two weeks or during illness. The study group was 30% children, 20% teens, and the rest adults. All models were adjusted for age, sex, race or ethnicity, asthma, and food allergy.
COVID-19 risk did not differ by age group. About 14% of children and adults and 12.1% of teens became infected. Children’s frequent HRV infections may help maintain their antiviral defenses.
Overall, the study shows recent rhinovirus infection lowers COVID-19 risk. The effect may come from a strong antiviral airway response. This response could both prevent infection and reduce viral load.
Lab experiments confirmed strong activation of these genes after HRV infection. Most people in the gene scan were HRV-negative before COVID-19 infection.This suggests HRV’s effect can last for weeks after infection.
Conclusion
Recent rhinovirus infection may lower COVID-19 risk and severity This protection is tied to stronger antiviral gene activity in the airway. The findings could guide future epidemic forecasting and treatment development.
Have an upcoming trip? Passport Health offers a wide variety of options to help keep you safe from disease, including vaccines. Call or book online to schedule your appointment today.
Logan Hamilton is a health and wellness freelance writer for hire. He’s passionate about crafting crystal-clear, captivating, and credible content that elevates brands and establishes trust. When not writing, Logan can be found hiking, sticking his nose in bizarre books, or playing drums in a local rock band. Find him at loganjameshamilton.com.
US - English
CA - English
Rest of World - English
