Dutch and American scientists are collaborating on a novel nasal spray designed to prevent influenza infections. The spray utilizes a broad-spectrum antibody that has demonstrated effectiveness against a wide range of flu strains, offering a potentially significant advancement in influenza prevention.
Currently, the primary defense against influenza is the annual flu vaccine. However, vaccine efficacy varies, averaging around 30 percent, according to the Dutch College of General Practitioners. The researchers behind the nasal spray believe their approach could surpass this level of protection. The spray aims to capture flu viruses within the nasal cavity *before* they can infect the body, a different mechanism than the vaccine’s stimulation of the immune system.
The key to this preventative measure is a newly discovered antibody, CR9114. This antibody targets a specific segment of the hemagglutinin (H) protein, a component found on the surface of influenza viruses. Crucially, CR9114 recognizes multiple subtypes of H, including those found in viruses that infect both humans and animals. This broad-spectrum activity suggests the spray could offer protection against emerging seasonal variants and even novel strains that jump from animals to humans, potentially reducing the need for yearly vaccine updates.
Initial testing has yielded promising results. The spray has proven effective in preventing infection in both mice and monkeys. Early human trials have indicated the spray is safe for use. While still in the experimental phase, these findings represent a substantial step forward in the development of a new influenza preventative.
Influenza remains a significant public health concern. Approximately 4,700 people die from influenza annually in the Netherlands, and an estimated 650,000 worldwide. The development of a more effective preventative measure could substantially reduce these numbers.
This research builds upon earlier work exploring novel approaches to respiratory virus protection. A separate study conducted by researchers at Harvard-affiliated Brigham and Women’s Hospital has yielded a drug-free nasal spray that forms a gel-like matrix to capture and neutralize viruses and bacteria. Preclinical studies of this spray demonstrated nearly 100% protection against respiratory infections, including those caused by COVID-19, influenza, and pneumonia-causing bacteria. This spray works by physically trapping pathogens in the nasal passages, preventing them from attaching to and infecting cells.
The Harvard research highlights the importance of the nasal passages as a primary entry point for respiratory viruses. When we breathe, we inhale droplets containing pathogens. These droplets attach to the cells lining the nasal passageways, where the virus replicates and can be released back into the air through coughing, sneezing, or even normal breathing. Both the Dutch/American antibody spray and the Harvard gel-matrix spray aim to interrupt this process at its earliest stage.
While vaccines and masks remain important tools in combating respiratory infections, these methods are not foolproof. Vaccines offer imperfect protection, and masks can leak or be improperly worn. The researchers developing these nasal sprays believe their approaches could provide an additional layer of defense, particularly valuable in safeguarding public health against both known and emerging respiratory threats.
The development of the Harvard spray, detailed in the journal Advanced Materials, was spurred by the recognition of the devastating impact respiratory pathogens can have, as demonstrated by the COVID-19 pandemic. Jeffrey Karp, distinguished chair in anesthesiology at BWH, emphasized the ongoing threat posed by seasonal influenza and the emergence of new viruses like COVID-19.
Further research and clinical trials are necessary to fully evaluate the efficacy and long-term safety of both nasal spray technologies. However, the initial findings are encouraging and suggest a promising new avenue for influenza prevention and broader respiratory protection. The Dutch-developed antibody spray, and the Harvard gel-matrix spray, represent innovative strategies to combat respiratory viruses at their point of entry, potentially offering a more robust and adaptable defense against a constantly evolving threat landscape.
