Live Animal Experiments Confirm that Nasal Drip of New Coronavirus Vaccine have an Immune Effect

According to a recent report on the 'Nature' website, through live experiments on small laboratory animals, two groups of researchers in the United States and China found that instilling candidate new coronavirus vaccines into the nasal cavity can have an immune effect and may be more effective than traditional injection vaccines. It is expected that after the vaccine is put into use, it will be provided to the public more efficiently and its social benefits cannot be underestimated.

In order to implement the nasal vaccination experiment, a team from the Washington University  School of Medicine designed a candidate vaccine that encodes the spike protein of the new coronavirus. It is through this spike protein that the new coronavirus completes the infection process by binding to the host cell. The researchers injected the vaccine into mice that have the human receptor corresponding to the protein after bio-engineering.

According to records and observations, after the vaccine was injected, no infectious virus was found in the lungs of the mice exposed to the new coronavirus, but a small amount of viral RNA was indeed detected. In contrast, no viral RNA was detected in mice vaccinated nasally, combined with other evidence to prove that nasal vaccination can achieve complete immunity.

At the same time, the research team of the First Affiliated Hospital of Guangzhou Medical University used another vaccine that encodes the spike protein of the new coronavirus to conduct experiments on rhesus monkeys. The researchers found that nasal vaccination is the same as traditional injection to pllay the effect of preventing virus infection. At the end of the experiment, the trachea and bronchus of rhesus monkeys who received different doses of injection or nasal drops were sampled to detect viral nucleic acid at 9 sites, and the results were all negative. In contrast, non-vaccinated monkeys detected high levels of virus in different locations.

The researchers said that the discovery of nasal vaccination methods enables people to instill vaccines on their own, making vaccination more convenient and easy. At the same time, the nasal immunization method is expected to reduce the potential immune problems caused by the adenovirus vector itself and achieve better immune effect.