Scientists are using artificial intelligence to develop nasal antivirals designed to stop viruses such as influenza and COVID-19 before they can enter human cells. The approach marks a shift from treating infections after they take hold to preventing them at the earliest possible stage.
Rather than focusing on vaccines alone, researchers are targeting the moment viruses attempt to fuse with cells or establish themselves in the nasal cavity. That entry point is often where respiratory infections begin.
AI Identifies a Critical Weak Point in Viral Fusion
One breakthrough comes from Washington State University, where scientists used AI and molecular simulations to identify a single interaction essential for viral entry. According to findings published in Nanoscale and reported by ScienceDaily on AI blocking viral cell entry, the team examined a fusion protein used by herpes viruses to invade cells.
By analysing thousands of amino acid interactions, the AI model isolated one interaction that played a decisive role in allowing the virus to fuse with host cells. Once researchers altered that interaction in laboratory tests, the virus could no longer enter the cells.
Lead researcher Jin Liu explained that AI made the discovery process dramatically faster. Instead of testing countless possibilities through trial and error, simulations narrowed the field to the most important interaction in advance.
Although the work focused on herpes viruses, the implications extend further. Viral fusion proteins are common across many pathogens, including respiratory viruses, which opens the door to broader antiviral strategies.
Nasal Antiviral Platform Targets Flu and Covid Directly
A second development comes from KAIST, where researchers have created an AI-engineered nasal antiviral platform designed to block rapidly mutating respiratory viruses. As detailed in MedicalXpress coverage of the AI nasal spray antiviral platform, the team redesigned interferon-lambda, a natural immune protein, to make it more stable and effective inside the nasal cavity.
Interferon-lambda plays a key role in blocking viral replication. However, previous nasal formulations broke down quickly due to heat, enzymes, and mucus. Using AI protein design, researchers reinforced weak structural regions and modified the protein's surface to improve stability and prevent clumping.
The redesigned protein was then combined with advanced delivery technology. Encapsulation in nanoliposomes and a specialised coating allowed the antiviral to adhere to the nasal lining for longer periods, increasing its protective effect.
Strong Results in Early Testing
In animal studies involving influenza, the AI-enhanced nasal spray reduced viral levels in the nasal cavity by more than 85 per cent. The treatment also remained stable at high temperatures and diffused effectively through thick mucus.
These characteristics make the platform particularly attractive for real-world use. A nasal spray that does not require strict cold storage could be deployed quickly during outbreaks and used in regions with limited infrastructure.
Researchers believe the same approach could be adapted for COVID-19 and future respiratory threats, especially those that evolve rapidly and evade vaccines.
A New Direction for Viral Prevention
Together, these studies highlight a growing trend in antiviral research. Instead of chasing ever-changing viral strains, scientists are focusing on universal mechanisms such as cell entry and early immune response.
By stopping viruses before infection begins, nasal antivirals could complement vaccines rather than replace them. Vaccines prime the immune system over time, while nasal sprays could offer immediate, localised protection during periods of high exposure.
What Comes Next
Researchers caution that further testing is needed before human use. Clinical trials will be required to confirm safety, dosage, and effectiveness across different viruses.
Still, the use of AI to accelerate discovery and design represents a decisive shift. As these tools improve, they may enable scientists to respond more quickly to emerging viral threats and reduce reliance on reactive treatments.
For now, the findings offer a glimpse of a future in which preventing infection could be as simple as a spray applied before viruses ever gain a foothold.
