Comparison of Four Serological Methods and Two Reverse Transcription-PCR Assays for Diagnosis and Surveillance of Zika Virus Infection
نویسنده :
تاریخ انتشار : 1397/03/02
T Zika virus (ZIKV) is a mosquito-borne flavivirus that is responsible for recent
explosive epidemics in the Americas. Notably, ZIKV infection during pregnancy
has been found to cause congenital birth defects, including microcephaly, and ZIKV
has been associated with Guillain-Barré syndrome in adults. Diagnosis and surveillance
of Zika in the Americas have been challenging due to similar clinical manifestations
and extensive antibody cross-reactivity with endemic flaviviral diseases, such
as dengue. We evaluated four serological and two reverse transcription-PCR (RT-PCR)
methods in acute-phase (mean day, 1.8), early-convalescent-phase (mean day, 16.7),
and late-convalescent-phase (mean, ~7 months) samples from the same individuals
in a long-term pediatric cohort study in Nicaragua. Well-characterized samples from
301 cases of Zika, dengue, or non-Zika, nondengue febrile illnesses were tested.
Compared to a composite reference, an in-house IgM antibody capture enzymelinked
immunosorbent assay (MAC-ELISA) and the NIAID-Biodefense and Emerging
Infections (BEI) MAC-ELISA measuring IgM yielded sensitivities of 94.5% and
70.1% and specificities of 85.6% and 82.8%, respectively. The NS1 blockade-ofbinding
ELISA measuring anti-ZIKV NS1 antibody levels yielded sensitivities of 85.0%
and 96.5% and specificities of 91.4% and 92.6% at early and late convalescence, respectively.
An inhibition ELISA detecting total anti-ZIKV antibodies had sensitivity
and specificity values of 68.3% and 58.3% for diagnosis and 94.0% and 98.6% for
measuring annual infection incidence. Finally, the ZCD and Trioplex real-time RT-PCR
assays detecting Zika, chikungunya, and dengue viruses both yielded a sensitivity of
96.1% and specificity of 100%. Together, these assays resolve the urgent need for diagnostic
and surveillance tools for countries affected by Zika virus infections