7% of visitors at NYC attraction shed respiratory virus in spring, summer
About 1 in 14 visitors to a major New York City tourist attraction were found to be shedding a common respiratory virus during spring and summer months — most of them without showing symptoms, according to a recently published study.
Jeffrey Shaman, PhD, associate professor of environmental health sciences at the Columbia University Mailman School of Public Health, and colleagues said their findings “indicate that significant levels of asymptomatic respiratory viral shedding exist during summer among the ambulatory population.”
They tested and surveyed 1,477 adults from April to July 2016. In all, 7.2% of the samples were positive for infections, including 71% that were positive for rhinovirus and 21.5% that were positive for coronavirus. The sampling also detected influenza, respiratory syncytial virus and parainfluenza.
Shaman told Infectious Disease News that the tourist attraction where participants were sampled and surveyed requested that it not be identified. In the study, it is described as “a collection point for both tourists and locals (that) provides a cross-section of potential participants who are broadly representative of the local and visiting populations of New York City.”
As for the findings, Shaman said it is important for clinicians to recognize the magnitude of asymptomatic infection and shedding.
“The population sampled were persons 18 and over, and most under 65 — not the demographic most impacted by viral respiratory infection. Yet here we found that 1 in 14 persons in this demographic during late spring and summer were shedding a common virus,” he said.
“This indicates that these viruses are everywhere,” Shaman continued. “The critical unanswered question is whether these asymptomatic infections contribute to the transmission of these viruses. That is, is an asymptomatic infection as contagious as a symptomatic infection? If they are just as contagious, then effective control of the spread these viruses — for example, the next pandemic — is much more challenging. Policies for control — in hospitals, schools, offices — will have to be reconsidered.”
Shaman said they repeated the study during cold and influenza season, but those results have not yet been published.
“The expectation was that the complement of viruses would shift and that infection rates would increase,” he said. – by Gerard Gallagher
Disclosures: Shaman and Columbia University report equity in SK Analytics.