Clinical Scenario:
A 10-year-old boy presents with a 3-day history of low-grade fever, intensely pruritic maculopapular rash and red eyes. The rash began on his trunk and subsequently spread to his limbs. He has mild arthralgia but no significant myalgia, vomiting, abdominal pain or bleeding. He is alert, well hydrated and hemodynamically stable.
His platelet count is 210 × 10⁹/L and hematocrit is normal.
Which of the following is the most likely diagnosis?
A. Chikungunya infection
B. Dengue fever
C. Measles
D. Zika virus infection
E. Chickenpox
Correct answer & Explanation:
Explanation
Correct answer: D. Zika virus infection
Zika virus infection in children is usually a mild, self-limiting illness. The characteristic clinical combination includes maculopapular rash, low-grade fever, non-purulent conjunctivitis and arthralgia. The rash is often pruritic, which is a useful clue in this case.
The absence of significant thrombocytopenia, bleeding, abdominal pain or plasma-leakage features makes dengue fever less likely. Chikungunya generally produces more prominent fever and severe polyarthralgia, whereas the arthralgia in this child is mild.
Measles typically presents with high fever, cough, coryza and conjunctivitis, followed by a maculopapular rash that begins on the face/hairline and spreads downward. Those respiratory prodromal features are absent here.
Chickenpox causes a vesicular, intensely pruritic rash with lesions in different stages of development, rather than a generalized maculopapular rash with conjunctivitis.
The combination of pruritic maculopapular rash + non-purulent conjunctivitis + mild fever + mild arthralgia therefore favors Zika virus infection. Clinical features alone, however, cannot reliably confirm Zika infection, and laboratory testing may be required when confirmation is clinically indicated.
Reference:
World Health Organization. Zika virus – Questions and answers. WHO Zika virus guidance
Centers for Disease Control and Prevention. Clinical Signs and Symptoms of Zika Virus Disease. CDC Zika clinical guidance
