Roseola Infantum ( sixth disease OR Exanthem Subitum ):
* Caused by human herpes virus -6 ( HSV - 6 ).
* Similar illness is caused by Parvovirus B-19 and Echovirus.
* Age involved : 6 months to 3 years.
* IP : 5 to 15 days.
* Clinically: Abrupt onset with high grade fever,
Mild pharyngitis and Coryza.
The temperature comes down rapidly in 3 to 4 days when a macular or maculopapular rash appears, starting from trunk and sometimes extending to the extremities and face.
Rash lasts for 24 hrs and disappear in 1-2 days without pigmentation or desquamation.
There is Occipital and post auricular lymphadenopathy.