Congenital Zika

Background

Infection with Zika virus
Mostly transmitted by mosquitoes (mainly Aedes aegypti), but can be sexually transmitted
Present in most of South and Central America including the Caribbean, sub-Saharan Africa, the Indian subcontinent, southeast Asia, and the Pacific islands
Transmission
- Detectable in serum of pregnant women for 10 weeks after symptom onset
- Detectable in semen for up to 188 days after symptom onset (but only 69 days for replication-competent virus)
  - Longest documented duration from symptom onset to sexual transmission is 32 to 41 days

Cranial morphology due to a disruption in the fetal brain sequence
- Severe microcephaly
- Overlapping cranial sutures
- Prominent occipital bone
- Redundant scalp skin
Brain anomalies
- Diffuse CNS calcifications, primarily subcortical
- Ventriculomegaly
- Polymicrogyria with cortical thinning
- Hypoplasia of the corpus callosum
- Decreased myelination
- Hypoplasia of the cerebellar vermis
Ocular anomalies (25 to 55%)
- Chorioretinal atrophy or scarring
- Focal pigmentary retinal mottling
- Optic nerve atrophy
- Microphthalmia, cataracts, and intraocular calcifications
Congenital contractures (5 to 15%)
- Arthrogryposis
- Club foot
- Congenital hip dislocation
- Other contractures, usually bilateral

Testing is only indicated for returned travellers with compatible symptoms
- CATMAT recommends against routine testing of asymptomatic pregnant women
Molecular testing is the mainstay of diagnosis
Serology also possible

For asymptomatic men and women: no recommendations
For women who have confirmed infection: wait 2 months after returning from the risk area before trying to conceive
For men who have confirmed infection: wait 3 months after returning from the risk area before trying to conceive
For men with compatible symptoms or confirmed infection and a pregnant partner: use barrier protection for the duration of pregnancy