A Universal Vaccine

Imagine if each year, a simple spray of medicine up the nose could protect you from respiratory viruses, the common cold, bacterial pneumonia, and even spring allergies.

That would transform medical practice.
Researchers are now inching closer to that possibility.
Scientists from institutions across the US have now developed a strikingly "universal" vaccine, which has protected mice against a range of viruses, bacteria, and even allergies.
The new GLA-3M-052-LS+OVA vaccine can be delivered as a nasal spray. Three doses protected mice from infection from SARS-CoV-2 and other coronaviruses for three months, and reduced the viral load in their lungs 700-fold, compared to unvaccinated mice.

The vaccine also accelerated the mice's immune response to SARS-CoV-2. While their lungs' adaptive immune systems typically take up to two weeks to respond to the virus, those with the vaccine took as little as three days to launch a counter-attack.
In follow-up tests, the vaccine was also found to protect the animals against bacterial infections. That included Staphylococcus aureus and Acinetobacter baumannii, both of which are often acquired in hospital settings and are becoming increasingly resistant to antibiotics.
Most surprisingly, the vaccine also cut the risk of asthma. When vaccinated mice were exposed to dust mites, their asthmatic responses, such as increased immune cell production and excess lung mucus, were reduced for three months as well.
In mice, a ‘universal’ vaccine can now protect against a host of viruses, bacteria, and allergies. It can even cut the risk of allergy-induced asthma.

Unlike other available vaccines, this new spray doesn’t require a jab, and it works using a unique mechanism.

The next step is to test the nasal spray in human clinical trials to ensure it is both safe and effective for our species.
Most vaccines work by presenting the immune system with a harmless fragment of a pathogen, allowing the body to prepare an arsenal of targeted antibodies to fight off the real thing if it ever appears. This is working on what's known as adaptive immunity.
This new vaccine works on a different mechanism. Rather than target the pathogen itself, it focuses on the body's response. Essentially, it's designed to link the two main arms of the immune system: The long-lasting but specific adaptive immunity that most vaccines work on, and the short-lived but diverse innate immunity.

The latter is our first line of defense against unfamiliar threats, but it generally wanes after a few days as the adaptive immune system learns to fight off the pathogen.

https://www.science.org/doi/10.1126/science.aea1260