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Question 740
Obstetric infection → Viral
Classification
Question
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Timing of VZIG after varicella exposure
Question Stem
A non-immune pregnant woman has had significant contact with chickenpox. Oral antiviral post-exposure prophylaxis is contraindicated. What is the latest interval after contact within which VZIG is considered effective?
Options
A
Within 24 hours
B
Within 72 hours
C
Within 5 days
D
Within 7 days
E
Within 10 days
Explanation
VZIG may be used for post-exposure prophylaxis when aciclovir or valaciclovir is contraindicated or causes significant adverse effects. It is considered effective when administered up to 10 days after contact. For a continuous exposure, such as household exposure, this interval is calculated from the appearance of the rash in the index case.
Option Validity
A) VZIG is not restricted to administration within 24 hours.
B) the effective window extends beyond 72 hours.
C) VZIG may be given later than 5 days after contact.
D) the guideline permits administration beyond 7 days after contact.
Further Reading
RCOG Green-top Guideline No. 13, Chickenpox in Pregnancy, section 4.3.