An investigational COVID vaccination, which may be taken in animal experiments, does not only protect the host, sondern also reduces the airborne spread of the virus to other close contacts.
The research conducted by Duke researcher Stephanie N. Langel, Ph.D., demonstrated the potential of a COVID vaccine that blends through the mucosal tissue to neutralize the SARS-CoV-2 virus, restricting infections and the spread of active virus in airborne particles.
Today, the findings are published in the journal Science Translational Medicine.
Because most of the world is under-immunized and this is especially true of children the possibility that a vaccinated person with a real illness may spread COVID to unimmunized family or community members is a public health danger. It''s a great benefit to develop vaccinations that also help prevent disease, but also reduce transmission to unvaccinated people.
Langel and colleagues -- including heads from Vaxart, a healthcare research non-profit, Lovelace Biomedical Research Institute -- tested a vaccine candidate that uses an adenovirus as a vector to express the spike protein of the SARS-CoV-2 virus. The human vaccination is designed to be taken as a pill.
In experiments using hamsters, the vaccination elicited a robust antibody response in blood and the lungs. When animals were exposed to the SARS-CoV-2 virus at high levels, they were less symptomatic than non-vaccinated hamsters, had reduced levels of infectious virus in the nose and lungs. Due of this, they did not shed as much virus through normal airborne exposures.
Mucosal immunizations increase the production of immunoglobulin A (IgA), the immune systems'' first line of defense against pathogens in the nose and lungs, making it less probable that those who have been vaccinated will transmit the infectious virus during a sneeze or a cough.
Our findings suggest that mucosal immunization is a viable strategy to reduce the spread of COVID through airborne transmission, according to Langel.
The primary aim of Langel''s research is to develop the SARS-CoV-2 virus, and further studies will be launched to detect the Omicron variants.
Susan Johnson, Clarissa I. Martinez, Nadine Peinovich, Emery G. Dora, Philip J. Kuehl, Hammad Irshad, Edward G. Barrett, Adam Werts, and Sean N Tucker are among the authors of this study.