Zebrafish Zika Virus (ZIKV) Infection Models

Introduction

Zika virus (ZIKV) is a mosquito-borne flavivirus transmitted primarily by Aedes aegypti and Aedes albopictus mosquitoes, with additional routes including sexual, vertical (mother-to-fetus), and blood transfusion transmission. While most ZIKV infections in adults are asymptomatic or cause mild febrile illness, infection during pregnancy can result in congenital Zika syndrome (CZS)—a devastating constellation of fetal abnormalities including microcephaly, cortical thinning, ventriculomegaly, ocular defects, hearing loss, and arthrogryposis. The 2015–2016 ZIKV epidemic in the Americas brought global attention to the virus, with Brazil alone reporting over 3,000 confirmed cases of ZIKV-associated microcephaly. The World Health Organization declared ZIKV a Public Health Emergency of International Concern in 2016. To date, no approved antiviral therapy or vaccine is available for ZIKV infection, and management remains supportive.

Zebrafish larvae have emerged as a tractable, physiologically relevant model for ZIKV research. Their external fertilization, optical transparency, and rapid neurodevelopment allow direct, real-time observation of viral infection dynamics and neuropathology. Crucially, zebrafish brain development shares conserved molecular pathways with humans, and ZIKV infection in zebrafish embryos recapitulates hallmark features of CZS—including microcephaly, neural progenitor cell depletion, and apoptosis.

Why Zebrafish?

• Real-Time Imaging: External development and optical transparency allow real-time imaging of ZIKV infection and neuropathology in live embryos.
• Conserved Neurodevelopment: Zebrafish neural progenitor biology mirrors that of the human fetal brain.
• High-Throughput Antiviral Screening: High-throughput antiviral screening in multi-well formats at a fraction of rodent model costs.
• Transgenic Reporters: Transgenic reporter lines (e.g., Tg(neurod:GFP), Tg(elavl3:GFP)) enable fluorescent tracking of neuronal damage.
• BSL-2 Compatible: Zebrafish ZIKV models can be established in standard BSL-2 facilities, unlike non-human primate models.

Available Zebrafish Disease Models

We provide a range of ZIKV infection configurations, from live-virus embryonic models to reporter-based and co-exposure formats:

Phenotypic Evaluation

Key Applications

• Antiviral Drug Screening: Identify and validate small molecules that inhibit ZIKV replication in a whole-vertebrate in vivo system.
• Neuroprotective Agent Discovery: Screen compounds that prevent or mitigate ZIKV-induced neural progenitor cell death and microcephaly.
• Mechanistic Studies: Dissect how ZIKV crosses the blood-brain barrier, infects neural progenitors, and disrupts neurodevelopment using transgenic reporters and live imaging.
• Viral Protein Function: Elucidate the role of individual ZIKV proteins (NS2A, NS4B, etc.) in neurotoxicity and identify host factors required for infection via CRISPR/Cas9 gene editing.
• Vaccine Antibody Evaluation: Test the capacity of vaccine-elicited antibodies to protect against ZIKV challenge in zebrafish embryos via passive transfer.

Study Examples

Zebrafish model reveals ZIKV-induced neurodevelopmental defects and identifies NS4A as a determinant of neuropathogenesis. The researchers established an in vivo ZIKV infection model using zebrafish larvae to investigate viral neuropathogenesis during early brain development. ZIKV-infected larvae developed reduced head size, impaired mobility, neural progenitor cell infection and depletion, and increased apoptosis, recapitulating several neurodevelopmental phenotypes associated with ZIKV infection. Transcriptomic analysis of neural progenitor cells revealed dysregulation of genes involved in cell survival and neuronal differentiation, including reduced expression of the glutamate transporter vglut1, which was associated with altered glutamatergic neuronal development.

Fig. 1. ZIKV infection in zebrafish larvae induces neurodevelopmental abnormalities and identifies NS4A as a key determinant of neuropathogenesis (Sow AA, Jamadagni P, et al., 2024).

Reference

1. Sow AA, Jamadagni P, et al. A zebrafish-based in vivo model of Zika virus infection unveils alterations of the glutamatergic neuronal development and NS4A as a key viral determinant of neuropathogenesis. PLOS Pathogens 20(12), e1012756 (2024).