It could be ugly, painful, and embarrassing. The lymphnodes around the neck would become infected, causing swollen lumps that sometimes festered, weeping puss, pain, and foul odor. It was called scrofula or the 'King's Evil' - not because kings caused it, but because certain kings were claimed to have the power to heal it. They didn't, of course, but sometimes the disease went into remission or altogether healed naturally, which went to the credit of the king. A king who was believed to have the power to heal was a magical, miraculous, powerful king indeed, seemingly deserving honor, glory, respect, and fear.
By the 17th century, the royal touch of British nobility had already been happening for hundreds of years. It had become part of the ceremony for the king to touch the infected patient after which the recipient of the touching would be given a coin or token as a parting gift, sort of the royal equivalent of a sacred relic blessed by clergy. The touch-piece usually had a hole in it for a ribbon to be strung through so it could be worn around the sick person's infected neck. The touch-pieces were made of gold, silver, copper, brass, or base metal, but what was supposed to be most important were the miraculous healing properties conveyed to it by the king.

The author has such a great way of storytelling!