The first UK case of congenital Zika syndrome

• We describe the first confirmed case of congenital Zika syndrome (CZS) in the UK. • Typical abnormalities can be identified on routine fetal anomaly screening scanning. • CZS can be diagnosed by obstetric imaging and laboratory testing of blood and amniotic fluid. Following the 2015–2016 Zika virus (ZIKV) epidemic in the Americas and Caribbean, cases have globally declined but persist in endemic regions like the Americas and Southeast Asia. While most infections are mild or asymptomatic, ZIKV during pregnancy can cause congenital Zika syndrome (CZS), leading to severe fetal malformations, including microcephaly. We report the first confirmed case of congenital Zika syndrome (CZS) in the UK. This case involves a 40-year-old Thai woman in her third pregnancy, complicated by a history of gestational diabetes and psoriasis managed with certolizumab. At 20 weeks’ gestation, routine scans identified fetal anomalies, including microcephaly, calcifications, and bilateral talipes. She disclosed first-trimester travel to Thailand, during which she developed a rash. She had travelled to both Bangkok and Phuket over a three-week period, between approximately 7–10 weeks’ gestation. A fetal MRI at 22 weeks showed features of congenital Zika syndrome (CZS) with severe abnormalities, including diminished brain development and limb deformities. Due to the poor prognosis, the patient opted for termination at 24 weeks. Fetal blood and amniotic fluid confirmed ZIKV RNA presence. Placental histopathology was unremarkable, and post-mortem was declined. A blood sample was tested for Zika virus (ZIKV) at the Rare and Imported Pathogens Laboratory (RIPL), Porton Down; the ZIKV PCR result was indeterminate, and the IgG was positive. Booking bloods taken shortly after travel were ZIKV PCR positive but IgG negative, demonstrating seroconversion and confirming recent ZIKV infection. Fetal MRI imaging revealed changes consistent with CZS. Fetal blood and amniotic fluid samples taken at the time of fetocide were also ZIKV PCR positive, confirming CZS. This case underscores the importance of up-to-date travel advice during pregnancy, taking a travel history and the consideration of CZS in fetuses with microcephaly and other typical ultrasound features.