This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pediatrics
Erythema infectiosum is seen in – 
Select and explain. 
A. Rubella, B. Fifth disease, C. Scarlet fever, D. Diphtheria
B: Fifth disease
Answer: B: Fifth disease 
Explanation: 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.