Table of contents
Expand All Topics
Zika virus infection
Background
Overview
Definition
The Zika virus is a mosquito-borne flavivirus that is associated with fetal anomalies in humans, including microcephaly and brain abnormalities.
1
Pathophysiology
Zika virus infection is transmitted primarily via the bite of infected mosquitoes (Aedes aegypti and Aedes albopictus species), although vertical and sexual transmission has been reported. When the mosquito's saliva containing the Zika virus is inoculated into human skin, the virus can infect epidermal keratinocytes, skin fibroblasts in the subcutaneous layer, and the Langerhans cells. After replication in these local tissue cells and the regional lymph nodes, the Zika virus can disseminate via the lymphatics and bloodstream to reach other organs and tissues, including the CNS, skeletal muscles, myocardium.
2
3
Epidemiology
In regions of the US with confirmed local transmission of Zika virus, the prevalence of birth defects potentially related to Zika virus infection is estimated at 3.0 per 1,000 live births.
4
Disease course
In adults, acute infection typically results in a self-limiting febrile illness, but may also lead to the development to neurological complications (meningitis, meningoencephalitis, Guillain-Barre syndrome). In neonates, Zika virus can lead to birth defects (microcephaly) and death.
1
Prognosis and risk of recurrence
The case fatality rate in neonates is estimated at 8.3% (95% CI, 7.2-9.6).
5
Guidelines
Key sources
The following summarized guidelines for the evaluation and management of Zika virus infection are prepared by our editorial team based on guidelines from the World Health Organization (WHO 2025) and the Center for Disease Control (CDC 2017).
1
2
3
4
5
6
7
Screening and diagnosis
Indications for testing, symptomatic patients
As per CDC 2017 guidelines:
Test for Zika virus infection in pregnant women with recent possible exposure and symptoms of Zika virus disease.
E
Test for Zika virus infection in pregnant women with recent possible exposure and prenatal ultrasound findings consistent with congenital Zika virus syndrome.
E
More topics in this section
Indications for testing (asymptomatic patients)
Indications for testing (preconception)
Diagnostic investigations
Clinical history: as per CDC 2017 guidelines, ask all pregnant women in the US and U.S. territories about possible Zika virus exposure before and during the current pregnancy, at every prenatal care visit.
E
More topics in this section
Serologic tests
Medical management
Fluid management: as per WHO 2025 guidelines, consider implementing protocolized oral fluid treatment in patients with suspected or confirmed non-severe arboviral disease.
C
implement monitoring of hydration and prevention of dehydration in all patients. Provide a cup or other means of measuring oral intake and give advice on how to record the amount taken. Administer volumes of fluids based on age and underlying medical conditions, such as congestive HF, CKD. ⁄
Show 4 more
More topics in this section
Antipyretic and analgesics
Corticosteroids
IVIG
Therapeutic procedures
Blood transfusion: as per WHO 2025 guidelines, avoid administering prophylactic platelet transfusion in patients with suspected or confirmed severe arboviral disease and a platelet count of < 50, 000/mcL who have no active bleeding.
D
consider administering platelet transfusion in specific circumstances, such as prevention of hemorrhage during surgery or other invasive procedures, and in patients receiving pre-existing anticoagulation treatment. ⁄