As chickenpox shots rose, what happened to shingles?
In Massachusetts, higher childhood varicella vaccine coverage tracked with less varicella but more reported herpes zoster—causality still uncertain.
Source
The incidence of varicella and herpes zoster in Massachusetts as measured by the Behavioral Risk Factor Surveillance System (BRFSS) during a period of increasing varicella vaccine coverage, 1998-2003
Inspect source passages
As chickenpox shots rose, what happened to shingles?
These passages occur verbatim in the stored paper text. They support the points listed below; they do not verify every statement in the explanation.
Coverage 48% to 89% in 19–35-month-olds
Vaccine coverage in Massachusetts 19–35-month-olds increased from 48 to 89 percent over the same 6-year period.
What paired trends accompanied rising coverage?
As varicella vaccine coverage in children increased, the incidence of varicella decreased and the occurrence of herpes zoster increased.
What they did
Investigators used Massachusetts BRFSS data (1998–2003) and vaccine coverage estimates to track varicella and herpes zoster incidence as childhood vaccination expanded.
What they found
Coverage in 19–35-month-olds rose from 48% to 89%. Varicella fell while age-standardized zoster incidence rose by 2.5 per 1,000 (90%) over 1999–2003. Authors caution vaccination is only one possible explanation.
The limits
What it doesn't show
Ecological survey trends cannot prove childhood vaccination caused the zoster increase.
Key terms
- Varicella
- Chickenpox from primary VZV infection.
- Herpes zoster
- Shingles from reactivation of latent VZV.
- Vaccine coverage
- Proportion of eligible children vaccinated.
- BRFSS
- Behavioral Risk Factor Surveillance System survey.
- External boosting
- Hypothesis that exposure to circulating VZV delays zoster by boosting immunity.
Flashcards
0 of 11 answers reviewed
Research intelligence for this paper
See its role on concept claims, tensions it is part of, placement history, and related discoveries.
Quiz yourself
As coverage rose, varicella incidence:
Common questions
What happened to chickenpox?
Incidence decreased as coverage rose.
What happened to shingles?
Age-standardized incidence increased.
Proven causal?
No—vaccination is one of several possible explanations.
Data source?
Massachusetts BRFSS plus coverage estimates.
More on Vaccination