Viral respiratory infections are common and usually result in only a few days of illness, but they can lead to severe disease. The focus on preventing and treating these infections has increased during the COVID-19 pandemic. Currently, doctors use antivirals, monoclonal antibodies, and convalescent plasma to try to prevent these infections from progressing. Researchers from Yale have found that a common antibiotic, neomycin, might reduce the risk of severe disease from viral respiratory infections.
Neomycin is an antibiotic that can be taken orally or used as a topical ointment, such as Neosporin. The research team investigated whether intranasal application of neomycin would boost the antiviral protection against SARS-CoV-2 and influenza A in mice. The study found that neomycin caused a strong immune response in mice and hamsters, protecting against infection with both viruses. Additionally, a group of healthy volunteers treated with Neosporin showed a similar immune response. Despite promising results, further research is needed to confirm the efficacy of neomycin in preventing and treating viral respiratory infections in humans.
The researchers treated mice with neomycin and found significantly increased levels of interferon-stimulated gene (ISG) expression, which is an immune response effective against viruses. When infected with SARS-CoV-2, the mice did not show typical signs of infection and most survived, unlike the control group. The neomycin-treated mice had lower levels of viral replication, indicating the antibiotic’s effectiveness against respiratory viruses. Hamsters treated with neomycin also showed resistance to infection and transmission of SARS-CoV-2.
A small pilot study in humans found that intranasal application of Neosporin ointment elicited a higher ISG response rate in healthy volunteers compared to control groups. This suggests that neomycin might stimulate the immune response and prevent viral infections in humans. However, more research is needed to determine the efficacy and safety of using neomycin for preventing and treating viral respiratory infections. Researchers caution that findings in rodents may not directly translate to human use, and further studies are warranted before considering clinical applications.
Using antibiotics to stimulate the innate immune response against respiratory viruses could be an alternative treatment strategy to antivirals, which may lead to the development of resistant strains. Neomycin is cheap, readily available, and easy to administer intranasally, making it a potential candidate for preventing and treating viral respiratory infections in humans. However, concerns about the safety and long-term use of neomycin need to be addressed through more extensive research and clinical trials. While the study’s findings are promising, further investigation is necessary to determine the practicality and effectiveness of using neomycin as a treatment for viral respiratory infections.
