The only single-stranded DNA (ssDNA) virus!
Pathophysiology
- Parvovirus B19 binds to the P antigen (globoside) on erythroid progenitor cells → cellular invasion → viral DNA enters the nucleus of erythroid cells → viral DNA replication → cytotoxicity → clinical manifestations + transient cessation of erythropoiesis
Clinical features
- Mild respiratory symptoms
- Rash
- Erythema infectiosum (fifth disease)
- Erythema infectiosum (fifth disease)
- Parvovirus B19-associated arthritis
- Severe anemia or transient aplastic crisis
- Hydrops fetalis
- Parvovirus B19 is a TORCH infection that can cause fetal death and miscarriage.
Childhood exanthems
Disease Pathogen Classic Presentation & Buzzwords Measles Measles virus 4 C’s (Cough, Coryza, Conjunctivitis, Koplik spots).
Rash: Face Body (Confluent).
Assoc: Vitamin A deficiency.Rubella Rubella virus Post-auricular LAD.
Rash: Face Body (spares 3 days, non-confluent).
Assoc: Congenital (PDA, cataracts, deaf), Adult arthritis.Roseola HHV-6 High fever breaks Rash appears.
Rash: Trunk Face.
Assoc: Febrile seizures.Fifth Disease Parvovirus B19 ”Slapped Cheek” Lacy/Reticular body rash.
Assoc: Aplastic crisis (Sickle Cell), Hydrops fetalis.Varicella VZV ”Dewdrop on a rose petal”.
Lesions in different stages of healing. t
Rash: Trunk Extremities.Scarlet Fever Strep pyogenes Sandpaper rash, Strawberry tongue, Circumoral pallor.
Assoc: Strep throat, Desquamation (palms/soles).
Fever-rash relationship
Link to original
- Measles (Rubeola): Fever first (with cough, coryza, conjunctivitis) → Rash appears 3-5 days later, spreading from head to toe.
- Rubella (German Measles): Low-grade fever → Rash appears 1-2 days later, spreading quickly from head to toe.
- Scarlet Fever: Fever and sore throat begin together → “Sandpaper” rash appears 1-2 days later.
- Erythema Infectiosum (Fifth): Low-grade fever/prodrome resolves → “Slapped cheek” rash appears days later.
- Roseola Infantum (Sixth): High fever for 3-5 days → Fever breaks → Rash appears after the fever is gone.
- Varicella (Chickenpox): Fever and vesicular rash appear at the same time (lesions in various stages).
