Pityriasis rosea is believed to be caused by a viral infection, specifically certain types of human herpesviruses (HHV).
While the exact mechanism isn't fully understood, research points towards human herpesvirus 6 (HHV-6) and human herpesvirus 7 (HHV-7) as the primary culprits. These are common viruses, and most people are exposed to them at some point in their lives.
Here's a breakdown:
- Viral Infection: Pityriasis rosea is not caused by bacteria or fungi, but by a virus.
- Human Herpesviruses (HHV-6 and HHV-7): These viruses are strongly implicated in the development of pityriasis rosea. The evidence suggests that reactivation of a latent HHV-6 or HHV-7 infection may trigger the rash.
- Susceptibility: Children and young adults are more commonly affected, but the reasons for this are not fully understood.
- Rare Recurrence: Fortunately, recurrence is rare. Most individuals who experience pityriasis rosea develop immunity and have only a small chance (around 2%) of getting it again.
In summary, pityriasis rosea is most likely triggered by a reactivation of the human herpesviruses HHV-6 or HHV-7, often affecting children and young adults, and rarely recurring.
