Reliability of a history of previous varicella infection in adults
M. R. Wallace, C. J. Chamberlin, L. Zerboni, M. H. Sawyer, E. C. Oldfield, P. E. Olson and A. M. Arvin
Internal Medicine Department, Naval Medical Center, San Diego, Calif 92134-5000, USA. mwallace@snd10.med.navy.mil
CONTEXT: Apparent second episodes of varicella are reported in
immunocompetent hosts, but laboratory confirmation of prior immune status
has rarely been possible. OBJECTIVE: To evaluate adult patients with
varicella who claimed to have had previous varicella to determine whether
they had true second episodes or primary cases with inaccurate clinical
histories. DESIGN: Adult subjects with varicella who enrolled in an
antiviral treatment trial were interviewed about a history of varicella.
The clinical course of varicella was documented prospectively in all
subjects. Serum samples that predated the acute illness were obtained from
the US Navy's central serum storage facility for subjects who reported a
previous episode of varicella. These stored samples were tested in parallel
by enzyme-linked immunosorbent assay, latex agglutination, and Western blot
for IgG antibodies to varicella-zoster virus (VZV). PARTICIPANTS: Twenty
military personnel with varicella and a history of the disease. SETTING: A
military hospital in San Diego, Calif. MAIN OUTCOME MEASURE: Presence or
absence of antibodies to VZV. RESULTS: Twenty (10.8%) of 184 adults with
serologically confirmed acute varicella reported a prior history of
varicella. The clinical course of these 20 patients did not differ from
those with no history of varicella. Serum samples that had been collected a
mean of 12.4 months (median, 12 months; range, 3 days to 34 months) before
the incident episode were available for 19 subjects. All 19 serum samples
lacked IgG antibodies to VZV. CONCLUSION: A history of previous varicella
infection in adults with varicella may not be reliable. True second
episodes of varicella are probably rare in immunocompetent adults.
