Birmingham Biotech highlights new Nature review on viral co-infections and the importance of nasal barrier protection
Findings from Nature Reviews Microbiology align with Birmingham Biotech’s focus on drug-free nasal barriers to support the body’s first line of defence
Birmingham, UK – 15 November 2025
Birmingham Biotech today highlighted the publication of a new review in Nature Reviews Microbiology examining how respiratory viruses interact when they infect the same person, and how these viral co-infections can influence disease severity. The company believes the findings reinforce the importance of strengthening the nose and upper airways as a first line of defence, an area where its NoriZite® Nasal Spray technology is specifically targeted.
The review, entitled “Respiratory viral coinfections: interactions, mechanisms and clinical implications” by Pallavi Deol and Tanya A. Miura, summarises current knowledge of how respiratory viruses such as influenza, respiratory syncytial virus (RSV), rhinoviruses and human coronaviruses can co-circulate and co-infect the same host. In some combinations, these interactions may dampen infection, but in others they can increase overall viral load, drive stronger inflammation and lead to more severe disease. Crucially, the authors highlight the nose and upper airways as a key site where these early interactions take place.
“This review is an important reminder that respiratory infections are rarely a simple ‘one virus at a time’ story,” said Michael Hsu, Founder and CEO of Birmingham Biotech. “In a world where multiple viruses often circulate together, it makes even more sense to focus on the nose – one of the main entry points into the body – and to ask how we can support that first line of defence in a safe, drug-free way.”
A dual-polymer nasal barrier at the point of entry
NoriZite® Nasal Spray was developed by Birmingham Biotech in collaboration with experts at the Healthcare Technologies Institute at the University of Birmingham. The spray is designed as a drug-free medical device that creates a physical barrier in the nasal cavity, helping to trap inhaled particles before they can reach the nasal lining.
The formulation combines two naturally derived polymers in a dual-polymer matrix:
Iota-carrageenan, extracted from red seaweed, which can bind and retain respiratory virus particles within a gel matrix. • Gellan gum, a fermentation-derived polysaccharide that helps the spray spread, adhere and remain across the nasal mucosa, forming a soft, gel-like layer.
Engineered to “plume” rather than “jet” when applied with a typical nasal spray applicator, NoriZite® can provide up to six times more surface coverage than standard sprays, and is
designed to remain in the nasal passage for up to six hours after application. This combination of coverage and residence time supports a long-lasting, non-specific nasal barrier at the point where respiratory viruses first arrive.
“The Nature review underlines how early events in the upper airways can shape the course of infection, especially when more than one virus is involved,” commented Professor Liam Grover, Professor of Biomaterials Science at the University of Birmingham and scientific lead on the NoriZite® programme. “NoriZite® was designed with exactly this in mind – to create a robust, mucoadhesive barrier in the nose that works with the body’s natural clearance mechanisms, without relying on pharmacologically active drugs.”
Supporting layered prevention, not replacing existing measures
Birmingham Biotech emphasised that the Nature review does not evaluate or endorse NoriZite®, and that the spray is not intended to replace vaccination, ventilation, hand hygiene, masks or clinical care. Instead, NoriZite® is positioned as an additional, local barrier tool within a broader, layered approach to respiratory health.
NoriZite® Nasal Spray:
Is a drug-free medical device, not a medicine, and contains no active pharmaceutical ingredients
Acts locally in the nasal cavity and is not absorbed into the bloodstream • Is designed to help reduce the risk of airborne particles entering and infecting nasal cells, in line with its barrier-based mode of action
“Our goal is to translate cutting-edge mucosal science into practical solutions that people can use alongside existing guidance,” added Hsu. “The latest work on viral co-infections strengthens our conviction that supporting the nose as a first line of defence is a sensible, science-aligned strategy.”
About NoriZite® Nasal Spray
NoriZite® Nasal Spray is a drug-free medical device developed by Birmingham Biotech and the Healthcare Technologies Institute at the University of Birmingham. Using a dual-polymer matrix of iota-carrageenan and gellan gum, the spray coats the nasal cavity, forming a long-lasting, gel-like barrier that helps trap airborne particles. NoriZite® is designed to complement – not replace – established public health measures such as vaccination, ventilation, hand hygiene and mask use.
About Birmingham Biotech
Birmingham Biotech is a UK-based life science company focused on developing and commercialising innovative, accessible solutions in diagnostics, protective technologies and mucosal health. Working closely with leading academic partners, including the University of Birmingham, the company aims to translate advanced materials science into products that address real-world health needs across global markets.
NoriZite® is a registered trademark of Birmingham Biotech Ltd. “Respiratory viral coinfections: interactions, mechanisms and clinical implications” by Pallavi Deol and Tanya A. Miura was published online in Nature Reviews Microbiology on 20 August 2025 (doi: 10.1038/s41579-025-01225-3).