School, child care and camp exclusions policies for chickenpox

Question 1

How can you test for VZV?

Answer 1

1. NP specimen for viral culture and PCR
   - PCR detects VZV DNA day before onset of rash (highest quant on day 1 of rash)
2. Vesicular fluid obtained within first 3 days of rash onset

• Correlation between higher viremia and severity of clinical disease

Question 2

What is breakthrough disease in varicella?

Answer 2

Varicella-like illness occurring >= 42 days after immunization with varicella

• presents atypically (maculopapular rash instead of vesicular rash)
• 72% occurs in immune compromised people
• People who develop varicella postimmunization are less contagious than unvaccinated cases

Question 3

When can children with chickenpox go back to school?

Answer 3

Return as soon as well enough to participate normally in all activities, regardless of state of rash
- excluding children after chickenpox is diagnosed is too late to prevent exposure

• Parents, particularly parents of immunosuppressed children, must be notified that chickenpox is in the classroom and counselled regarding VZV incubation period, signs, and symptoms
• Parents of immunosuppressed children should be encouraged to seek medical advice to determine whether PEP is warranted

Question 4

What to do about chickenpox in camp settings?

Answer 4

• complete hx of varicella dz or immunization before camp start dates should be obtained from all attendees
• make list of potentially susceptible people
• offer immunization if no contraindications to people susceptible to VZV
• review varicella exclusion policies, taking immune status of attendees into consideration
• if camp has immunocompromised people, should exclude:
• • campers/staff with active VZV disease
• • people who had exposure in past 21 days and aren’t immune