Researchers from the Universities of Basel and Zurich have successfully reconstructed the genome of the 1918 influenza virus using a preserved sample from an 18-year-old patient who died in Zurich during the first wave of the pandemic. This study provides new insights into the virus's early adaptations to human hosts.
The analysis revealed three key mutations in the Swiss strain of the virus: two that enhanced resistance to antiviral components of the human immune system, and one that improved the virus's ability to bind to human cell receptors, increasing its infectiousness. These adaptations were present at the outset of the pandemic and persisted throughout its duration.
To achieve this, the researchers developed a novel method for recovering ancient RNA fragments from preserved specimens, enabling the reconstruction of the virus's genome. This approach opens the possibility for studying other ancient RNA viruses and understanding their evolution.
The findings underscore the importance of studying past pandemics to inform future public health responses. By understanding how viruses adapt to human hosts over time, scientists can develop models to predict and mitigate the impact of future outbreaks.