1. j berry j berry United Kingdom says:

    If the outermost layer of skin is dead skin, then maybe material from the outside is kept away by the costant shedding of skin. If the shedding is too fast or is scratched away, it allows infection. Also if the skin itches,  the finger nails be dirty or infected .

The opinions expressed here are the views of the writer and do not necessarily reflect the views and opinions of News Medical.