University of North Carolina School of Medicine researchers carried a study to find the impact of Covid-19 infection on smokers, non-smokers, and e-cigarette users.
They found that e-cigarette users exhibited significantly altered immune responses to a model of influenza virus infection, suggesting increased susceptibility to disease.
The findings were published in the
First author Meghan Rebuli, assistant professor in the UNC Department of Pediatrics and member of the UNC Center for Environmental Medicine, Asthma, and Lung Biology, said in a statement: “In many of the study participants, we observed more changes to the immune response in e-cigarette users than we did in smokers.”
He added: “All of these factors have the potential to adversely affect response to a virus and immunity post-infection. While we used influenza as a model, this suggests that e-cigarette users are likely more susceptible to respiratory viruses than are non-smokers, and this likely includes SARS-CoV-2, the virus that causes coronavirus.”
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Methodology used
For the study, the researchers intended to know what happens when e-cigarette users are exposed to a respiratory virus.
Non-smokers, cigarette smokers, and e-cigarette users aged 18-40, were inoculated with live attenuated influenza virus (LAIV) vaccine — a well-established model of influenza infection in the Jaspers lab — to safely examine the innate immune response.
The researchers collected nasal epithelial lining fluid, urine, blood, nasal epithelial lining fluid, among other markers of viral load pre- and post-inoculation.
The researchers noticed that there was not much of a difference in some of the markers in the three groups. However, they noticed expected increases in nasal epithelial lining fluid anti-LAIV IgA — which is a potential indicator of developed immunity post-infection — did not occur in e-cigarette users and cigarette smokers.
Further, LAIV-induced gene expression changes in nasal biopsies differed in cigarette smokers and e-cigarette users as compared to non-smokers, with a greater number of genes changed in e-cigarette users. This could result in decreased expression of immune genes critical for defence against viruses and generation of immune memory.
Rebuli said: “We don’t know for sure if people who vape are more susceptible to Covid-19, or if vaccines would be less effective for them.”
“But we know we never want to see suppression of genes, proteins, and antibodies involved in our immune response. And this is what we see in our data related to smoking and e-cigarette use,” she said.
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