Erythema infectiosum is seen in –
Erythema infectiosum also was known as the fifth disease is caused by Parvo Virus (B-19).

Erythema infectiosum

Most common clinical manifestation of human parvovirus infection.
Most common complication is arthritis
Incubation period is 4 to 14 days.
Prodromal illness is minimal

Characteristics skin lesions appear in 3 stages :

Ist phase → Cheeks are erythematous giving appearance of slapped cheeks.
2nd phase → Itching erythematous maculopapular rash on extensor surface (Palms and soles spared).
3rd phase → begins to fade and disappears in about 2 weeks.
Rubella
Fifth disease
Scarlet fever
Diphtheria