Volume 23, Number 3—March 2017
Zika Virus RNA Replication and Persistence in Brain and Placental Tissue
|Pregnancy or infant outcome||No. (%) case-patients, n = 52||Trimester of maternal symptom onset
||Zika virus–positive case-patients, by tissue RT-PCR, no. (%), n = 32|
|First, no. (%), n = 27||Second or third, no. (%), n = 24|
|Spontaneous abortion||11 (21)||11 (41)||NA||9 (82)|
|Elective termination||3 (6)||3 (11)||NA||3 (100)|
|Intrauterine fetal demise†||3 (6)||1 (4)||2 (8)||0|
|Infant with microcephaly (fatal outcome)‡||8 (15)||8 (29)||NA||8 (100)|
|Infant with microcephaly (nonfatal outcome)§||5 (10)||3 (11)||1 (4)||4 (80)|
|Apparently healthy infant||22 (42)||1 (4)||21 (88)||8 (36)|
*Of 32 case-patients with positive Zika virus tissue RT-PCR results, maternal serology (IgM and plaque-reduction neutralization test) results were consistent with recent flavivirus infection (9 case-patients) and consistent with recent Zika virus infection (4 case-patients). Zika virus infection was confirmed for 5 patients by RT-PCR at a state laboratory. For the remaining 14 case-patients, no maternal testing was performed. Of 20 case-patients with negative Zika virus tissue RT-PCR results, maternal serology (IgM and plaque-reduction neutralization test) results were consistent with recent flavivirus infection for 12 case-patients (11 who had live-born, apparently healthy, infants, and 1 who had intrauterine fetal demise). For 2 case-patients, maternal serology results were negative for Zika virus IgM, and for 6 case-patients, no maternal serologic testing was performed. Zika virus infection was confirmed for 1 case-patient by RT-PCR at a state laboratory. NA, not available; RT-PCR, reverse transcription PCR.
†Including 1 with microcephaly.
§Information about timing of symptom onset was unavailable for 1 case-patient with Zika virus–positive tissue RT-PCR results. Nonfatal, according to the information received from the case submitters as of the date of testing.