TABLE 2 .
Sources of sera and methods used to define immunoreactivity, sensitivity, and specificity with Center for Infection and Immunity arboviral peptide array and ZIKV-NS2B-concat ELISAd
| Virus name and serotype | Phase (time point of sample collection after onset of illness)e | Immune status | No. of samples from source: |
No. of samples positive for ZIKV NS2B peptide/total no. (%) by assay: |
Reference assays used | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| Nicaragua | Thailand | Erasmus MC | WC/PHL | Banked sera, CII | CII-arboviral peptide array | ZIKV-NS2B-concat ELISA | ||||
| ZIKV | Acute | DENV immune | 9 | 5/9 (55) | 5/9 (55) | CDC Trioplex assay, ZCD triplex assay, CDC ZIKV monoplex assay, DENV-CHIKV multiplex assay, BOB-ELISAg | ||||
| DENV naive | 21 | 9/21 (43) | 7/21 (33) | |||||||
| Total | 30 | 14/30 (47)f | 12/30 (40) | |||||||
| Early convalescence | DENV immune | 25 | 24/25 (96) | 24/25 (96) | ||||||
| DENV naive | 65 | 64/65 (98) | 62/65 (96) | |||||||
| Total | 90 | 88/90 (98) | 86/90 (96) | |||||||
| Late convalescence | DENV immune | 8 | 6/8 (75) | 5/8 (62) | ||||||
| DENV naive | 10 | 6/10 (60) | 5/10 (50) | |||||||
| Total | 18 | 12/18 (67) | 10/18 (55) | |||||||
| Total ZIKV | 114/138 (82) | 108/138 (78) | ||||||||
| DENVa | CII-ArboViroPlex qPCR NAT assay, RVPs, DENV PRNTh | |||||||||
| NA | Acute | NA | 12 | 0/12 | 1/12 (8) | |||||
| NA | Early convalescence | Primary | 18 | 1/18 (5) | 1/18 (5) | |||||
| Secondary | 11 | 1/11 (9) | 1/11 (9) | |||||||
| Total | 29 | 2/29 (7) | 2/29 (7) | |||||||
| DENV1 | Late convalescence | Primary | 18 | 3 | 0/21 | 1/21 (5) | ||||
| Secondary | ||||||||||
| Total | 21 | 0/21 | 1/21 (5) | |||||||
| DENV2 | Late convalescence | Primary | 17 | 3 | 1/20 (5) | 2/20 (10) | ||||
| Secondary | 6 | 0/6 | 1/6 (17) | |||||||
| Total | 26 | 1/26 (4) | 3/26 (12) | |||||||
| DENV3 | Late convalescence | Primary | 9 | 3 | 0/12 | 0/12 | ||||
| Secondary | 9 | 0/9 | 1/9 (11) | |||||||
| Total | 21 | 0/21 | 1/21 (5) | |||||||
| DENV4 | Late convalescence | Primary | 4 | 3 | 0/7 | 0/7 | ||||
| Secondary | ||||||||||
| Total | 7 | 0/7 | 0/7 | |||||||
| NA | Late convalescence | Primary | 8 | 1/8 (12.5) | 1/8 (12.5) | |||||
| Secondary | ||||||||||
| Total | 8 | 1/8 (12.5) | 1/8 (12.5) | |||||||
| Total DENV | 4/124 (2) | 9/124 (7) | ||||||||
| CHIKVb | Acute | Natural infection | 6 | 6 | 1/12 (8) | 1/12 (8) | CDC Trioplex assay, method in reference 34, Euroimmun Arbo mosaic CHIKV IFAi | |||
| Convalescence | Natural infection | 6 | 6 | 0/12 | 0/12 | |||||
| Total CHIKV | 1/24 (4) | 1/24 (4) | ||||||||
| WNVc | Convalescence | Natural infection | 5 | 0/5 | 0/5 | Euroimmun anti-WNV ELISA (IgG/IgM) | ||||
| YFVc | NA | Vaccinated | 10 | 1/10 (10) | 1/10 (10) | Euroimmun flavivirus mosaic IFA | ||||
| TBEVc | NA | Vaccinated | 3 | 0/3 | 0/3 | Serion ELISA classic TBEV IgG and IgM tests | ||||
| JEVc | Convalescence | Natural infection | 1 | 0/1 | 0/1 | Euroimmun flavivirus mosaic IFA | ||||
| NA | Vaccinated | 3 | 1/3 (33) | 1/3 (33) | ||||||
| Total JEV | 1/4 (25) | 1/4 (25) | ||||||||
| Controlc | NA | Negative for above viruses | 21 | 1/21 (5) | 1/21 (5) | CII-Arbo ViroPlex qPCR NAT assay | ||||
DENV late-convalescent-phase (DENV-immune and ZIKV-naive) samples were collected before declaration of the ZIKV outbreak in Nicaragua. DENV acute-phase samples were collected from returning travelers during the 2016 ZIKV outbreak in Puerto Rico. DENV early-convalescent-phase samples were collected in 2016 during the ZIKV outbreak in Nicaragua.
CHIKV samples from Nicaragua were collected in 2014 to 2015 just before the ZIKV outbreak. CHIKV samples from WC/PHL were collected in 2016 from returning travelers during the ZIKV outbreak in Puerto Rico. CHIKV samples from Erasmus Medical Centre were collected in 2014 before declaration of the ZIKV outbreak in the Americas.
Other control group samples were collected before recognition of the ZIKV outbreak in the Americas.
Abbreviations: NA, no information available; CII, Center for Infection and Immunity; MC, Medical Centre; qPCR, quantitative PCR; NAT, nucleic acid test.
Acute phase, 1 to 6 days; early convalescent phase, ~14 to 21 days; late convalescent phase, ~6 months.
Total values by virus are highlighted in bold.
ZIKV cases were confirmed by real-time RT-PCR of serum, using the CDC Trioplex assay, the ZCD triplex assay (36), or in some cases the CDC ZIKV monoplex assay (37) in parallel with a DENV-CHIKV multiplex assay (38). Anti-ZIKV antibodies were detected by BOB-ELISA (23).
DENV acute-phase samples were tested by CII-ArboViroPlex qPCR NAT assay (Center for Infection and Immunity, 2017). In Nicaraguan samples, anti-DENV antibodies at the time of collection were detected by reporter virus particle neutralization assay (RVPs) (35). DENV convalescent-phase sera from Thailand were tested for positivity with DENV PRNT (40).
CHIKV acute-phase samples were tested by CDC Trioplex assay. Anti-CHIKV antibodies were detected by the method described in reference 34 or Euroimmun Arbo mosaic CHIKV IFA.