Covid vaccine you inhale could stop even mild infection

INHALING a powdered vaccine could be a new way to tackle Covid. it could be more convenient, and more effective, than injected versions — stopping the virus taking hold in the first place.

The vaccine is designed to get straight into the respiratory tract where it primes immune cells to defend the body, to stop the infection at the earliest stage.

new research shows it triggers immediate and strong production of immune cells that attack the virus before it can establish itself in the lungs, reported the journal nature.

injected vaccines provide protection against developing severe disease and are estimated to have prevented 14.4 million deaths worldwide, reported the Journal of Paediatrics and Child health in 2022. They are given into a muscle and once the vaccine gets into the blood, it primes the immune system.

The powdered vaccine is made up of tiny spheres that contain the protein (or antigen) that’s unique to SaRS-CoV-2, the virus that causes Covid-19.

it is inhaled into the nose where it is rapidly absorbed by blood vessels that line the nasal cavity. This is also where the virus enters the body (it’s spread via respiratory droplets).

The respiratory tract (which includes the nasal cavity) and lungs have their own immune system defences in the mucus layers. When the powdered vaccine arrives in the respiratory tract, the immune cells there identify the protein, then attack it, and remember it. if the real virus then arrives, the immune system cells are primed to repel it.

Research by scientists at the Chinese academy of Sciences in Beijing, who developed the vaccine, shows that it triggers an immediate immune response. Conventional vaccines take up to 14 days to be fully effective. and because it can be inhaled it is an option for people with needle phobia, thought to affect up to 10 per cent of the population. Multiple antigens can be added to the spheres, so it could be adapted for Covid mutations, or other viral infections.

ANOTHER advantage of the powdered vaccine, they say, is that it doesn’t need to be kept frozen or refrigerated, cutting costs and widening availability.

Tests on mice, hamsters and monkeys all showed that the powdered vaccine triggered immediate immune reactions that were long lasting. it was successful in blocking both infection and transmission. human trials are now planned.

Peter openshaw, a professor of experimental medicine at imperial College london, said: ‘ The inhalable vaccine needs to be tested in humans but the results add to growing evidence that needle-free vaccines given via sprays or nebulisers might have significant advantages in preventing infections that get in via the lung and nose.’