Universal Nasal Vaccine Shows Promise Against COVID, Influenza, Pneumonia: Research

For decades, scientists have pursued the idea of a universal vaccine capable of protecting against a wide range of infectious threats. Now, researchers at Stanford Medicine report a major step toward that goal. In a mouse study published in Science, the team developed an experimental nasal spray vaccine that protected against multiple respiratory viruses, bacteria, and even allergens for months.

The study showed that vaccinated mice were protected against SARS-CoV-2 and other coronaviruses. The vaccine also reduced allergic responses to house dust mites, a frequent trigger of asthma.

Unlike traditional vaccines, which rely on antigen specificity—training the immune system to recognize a specific piece of a pathogen—this experimental vaccine works differently. However, rapidly mutating viruses such as influenza and SARS-CoV-2 often change their surface proteins, requiring updated vaccines and boosters.

Instead of targeting a specific pathogen component, the new nasal vaccine mimics immune signaling pathways. It activates both the innate and adaptive immune systems in a coordinated way. In this case, researchers found a way to sustain innate immune activation in the lungs for months by recruiting T cells that continuously send activating signals to innate immune cells.

The vaccine formulation, called GLA-3M-052-LS+OVA, includes immune-stimulating compounds that activate toll-like receptors, along with a harmless protein called ovalbumin (OVA) to draw T cells into lung tissue. In the study, mice received the vaccine intranasally. After three doses spaced one week apart, they were protected against SARS-CoV-2 and related coronaviruses for at least three months.

Encouraged by these findings, researchers also tested the vaccine against bacterial infections and allergic responses. Vaccinated mice were protected against Staphylococcus aureus and Acinetobacter baumannii for approximately three months

Researchers describe the effect as a “double defense.” The sustained innate response suppresses pathogens early, while the adaptive system rapidly generates targeted antibodies and virus-specific T cells—within as little as three days, compared to about two weeks in unvaccinated mice.

If similar results are achieved in humans, a single seasonal nasal spray might one day offer broad protection against respiratory viruses and even certain allergens, potentially transforming preventive medicine.

REFERENCE: Haibo Zhang, Katharine Floyd, Zhuoqing Fang, Filipe Araujo Hoffmann, Audrey Lee, Heather Marie Froggatt, Gurpreet Bharj, Xia Xie, Haleigh B. Eppler, Jordan Mariah Santagata, Yanli Wang, Mengyun Hu, Christopher B. Fox, Prabhu S. Arunachalam, Ralph Baric, Mehul S. Suthar, Bali Pulendran. Mucosal vaccination in mice provides protection from diverse respiratory threats. Science, 2026; DOI: 10.1126/science.aea1260