According to Water's Edge Dermatology, mollusca on the skin are a bumpy rash caused by an infection called molluscum contagiosum, which is technically a poxvirus. The bumps are very small, usually only 2 to 5 millimeters in diameter, and can appear anywhere on the body. They are highly contagious and emerge in many shades, from flesh-toned to pink or red, depending on how agitated they become.
Molluscum contagiosum only infects the skin and does not exhibit symptoms other than unsightly bumps. It does not spread to other areas of the body, such as the internal organs, or progress into other dangerous health complications, states Water's Edge Dermatology. Although the condition is benign, many people mistake the appearance of the infection as something far more alarming. The bumps are usually smooth and firm but can become itchy and inflamed for some people.
Usually, people with a molluscum contagiosum outbreak grow between 10 and 20 bumps in a cluster. Because the virus is spread through skin-to-skin contact, these clusters commonly appear in places where people are most likely to touch one another, such as on the face and groin. People with weakened immune systems can experience much larger collections of bumps and can have a difficult time eradicating the virus. Water's Edge Dermatology notes that the virus is much more common in children than in adults.