Life Cycle. The life cycle of a louse begins as an egg, also called a nit. The nit is a 1mm whitish-yellow speck that attaches itself firmly to an individual hair strand close to the scalp.
Pityriasis rosea is a relatively common skin condition that causes a temporary skin rash of raised, red scaly patches on the body.The rash can be very itchy and usually clears within 2-12 weeks, but on rare occasions can last up to 5 months.ityriasis rosea is a relatively common skin condition that causes a temporary skin rash of raised, red scaly patches on the body.
Pityriasis Lichenoides can occur in two forms: acute and chronic, but there is an overlap between them. The acute form is called: PLEVA which is Pityriasis Lichenoides et Varioliformis Acuta also known as Mucha-Habermann's disease.The chronic form is called Pityriasis Lichenoides Chronica.They are mild forms of lymphocytic vasculitis.he exact causes of PLEVA and PLC are not known. They are definitely not caused by a fungus or bacterial infection, and they are not caused by anything that a person has eaten. They are also not due to any known type of allergic reaction. A virus is the most likely cause.