Scientists have developed a novel flu treatment that they believe holds the potential to protect against any strain of influenza virus. The study was led by scientists at the University of St Andrews, Scotland, and has been published in the journal Proceedings of the National Academy of Sciences of the United States of America.
Influenza strikes globally every year. Although the flu virus can infect anyone, young children, adults over the age of 65 and those with pre-existing medical conditions are particularly at risk of developing complications as a result of infection. According to the WHO, annual epidemics cause between 3-5 million cases of severe illness and claim approximately 250,000-500,000 lives. The emergence of strains from avian sources is also of particular concern because of their potential ability to cause pandemics.
Although some antiviral treatments exist for flu, such as Tamiflu, they are limited in their effectiveness due to influenza’s high mutability rate, and recent studies have suggested that they may be a waste of money. Prevention is also better than treatment but vaccines take a long time to develop after new strains emerge. There has therefore been a need to develop novel approaches to tackle flu that can combat not only seasonal flu but emerging flu strains from animal sources also.
Influenza viruses bind to receptors found on cells within the respiratory tract which possess a sugar molecule called sialic acid. To exploit this, the researchers developed carbohydrate-binding molecules that were specific for sialic acid, called biologics, which effectively blocked the flu receptors, preventing the virus from entering the cell to initiate replication.
Rather impressively, mice were protected from lethal doses of the pandemic H1N1 flu virus when given a single intranasal dose of the treatment 7 days prior to challenge with the virus. What’s also interesting is that the low level of viral replication that was still able to occur in these mice was sufficient to generate an immune response. This suggests that the mice may be protected from future exposure to the same virus. The biologics also appeared to stimulate an inflammatory response, which could be a contributing factor to their effectiveness.
Furthermore, this new treatment may be effective in preventing other respiratory pathogens that also use sialic acid receptors for cell entry, although this has not been tested yet.
“We believe that our approach has the potential to be used as a preventative against any current and new virus that emerges, such as H5N1, H7N9 and the very recent H10N8,” said Professor Taylor, lead researcher of the study.