Childhood colds do not prevent coronavirus infection, study finds

A study published in Cell suggests that prior antibodies to seasonal coronaviruses have no effect on SARS-CoV-2. Scott Hensley, PhD, an immunologist at the University of Pennsylvania, and his team of researchers noted that most people are exposed to seasonal coronaviruses by age 5 years. As a result, roughly 1 in 5 people carry antibodies that recognize the new coronavirus. However, these antibodies are not neutralizing, nor do they mitigate the severity of symptoms following infection, researchers found. The team examined samples from 251 people who donated blood to the University of Pennsylvania prior to the pandemic and also later contracted COVID-19. These individuals had levels of antibodies able to recognize the new coronavirus at about the same levels as those seen in blood samples drawn from 251 people who remained uninfected. The levels indicated no relationship to the clinical outcome in any of the patients. Marion Pepper, PhD, an immunologist at the University of Washington in Seattle who was not involved in the study, notes that the coronavirus’ spike protein is the most distinctive part of the virus, so it is logical that antibodies to seasonal viruses would be unlikely to recognize and disarm it.