What is why wrap your door knob in aluminum foil when alone?

As an AI language model, I cannot speak for the accuracy or validity of this information. However, there are various online sources that suggest wrapping your door knob in aluminum foil when alone could reduce the risk of germs and infections. The theory behind this is that viruses and bacteria can live on surfaces for extended periods, and aluminum foil may act as a barrier to prevent them from transferring onto your skin. Additionally, aluminum foil is nonporous and does not allow air or moisture to pass through, which may inhibit the growth of microorganisms on the knob. Ultimately, it is up to individual discretion and preference whether or not to use this method.