Volume 27, Number 5—May 2021
Dispatch
Evaluating Differences in Whole Blood, Serum, and Urine Screening Tests for Zika Virus, Puerto Rico, USA, 2016
Table 2
Number of positive tests for Zika virus among 514 asymptomatic pregnant women tested by specimen type and assay, Puerto Rico, USA, October 1–November 4, 2016*
Category |
NAAT |
IgM | ||
---|---|---|---|---|
No. positive tests/no. tested (%) |
Median Ct value (range) |
No. positive tests/no. tested (%) |
||
Specimen type | ||||
Serum | 20/509† (4) | 37.2 (29.8–37.9) | 45/508‡ (9) | |
Urine | 10/503§ (2) | 37.4 (36.2–37.9) | ||
Whole blood |
8/507¶ (2) |
34.2 (29.8–36.7) |
||
Total positive tests among pregnant women by test type# |
28/514 (5) |
45/508 (9) |
||
Total positive tests among pregnant women by any test or specimen type# | 69/514 (13) |
*Ct values were not compared across specimen types. IgM was performed only on serum specimens. Ct, cycle threshold; NAAT, nucleic acid amplification testing. †5 serum specimens from asymptomatic women were unable to be provided for Trioplex NAAT. ‡6 serum specimens from asymptomatic women were unable to be provided or were inconclusive for Zika virus IgM testing. §11 urine specimens from asymptomatic women were unable to be provided for Trioplex NAAT. ¶7 whole blood specimens for asymptomatic women were unable to be provided for Trioplex NAAT. #The denominator includes pregnant women who were missing a test type.
1These authors contributed equally to this article.