Firstly, What Are Verrucae?
Verrucae, also known as Warts, are caused by an infection with the human papilloma virus (HPV). The virus causes an excess amount of keratin, a hard protein, to develop in the top skin layer. They typically vary in appearance and may develop singly or in clusters.
The infection can also be transmitted in-directly from contaminated objects or surfaces, such as the area surrounding a swimming pool. You are more likely to get infected if your skin is wet or damaged.
Verrucae are extremely contagious and are usually acquired in wet public places, such as, swimming pools and shower/changing rooms.