PaediatricsPending review
Chickenpox
Primary varicella-zoster infection spreads by viraemia to the skin in successive waves, so lesions at different stages coexist at any one time, and the virus's retreat into dorsal root ganglia rather than true clearance is what allows it to return later as shingles.
In a nutshell
Varicella-zoster virus reaches the skin in successive waves of viraemia, so lesions of different ages (macule to crust) coexist at once: the diagnostic hallmark. The virus then retreats to dorsal root ganglia in lifelong latency, able to reactivate later as shingles. Disease is usually mild and self-limiting in healthy children but can be severe in neonates, pregnant women and the immunocompromised.
Classic presentation
A child with mild fever and malaise develops an itchy vesicular rash starting on the trunk and face, spreading to the limbs, with lesions at multiple stages of evolution present together.
Key points
- Lesions at different stages simultaneously (macule, papule, vesicle, pustule, crust) is the key diagnostic feature, reflecting successive waves of viraemia.
Educational content pending clinical review. Not medical advice.