What are the prevention and treatment options for Zika virus infection?

Zika Virus Prevention and Treatment

There is no specific treatment or vaccine for Zika virus infection; management is entirely focused on prevention through mosquito bite avoidance and sexual transmission precautions, with supportive care only for symptomatic cases. 1, 2

Prevention Strategies

Mosquito Bite Prevention (Primary Route)

• Use EPA-registered insect repellents containing DEET when outdoors, which is effective for disease mitigation 3, 4
• Wear long sleeves and pants, and use permethrin-treated clothing and gear 3
• Stay in air-conditioned or well-screened indoor environments 3
• Pregnant and lactating women can safely use all EPA-registered insect repellents according to product labels 3

Sexual Transmission Prevention

For men with possible Zika exposure planning to conceive:

• Wait at least 3 months after symptom onset (if symptomatic) or last possible exposure (if asymptomatic) before engaging in unprotected sex 5, 1
• This 3-month waiting period is based on evidence showing Zika virus RNA detection in semen declines substantially after 90 days, with only ≤7% of men having detectable viral RNA beyond this timeframe 5

For men whose partner is currently pregnant:

• Use condoms consistently and correctly during all sexual activity or abstain from sex for the entire duration of pregnancy 1

For couples not trying to conceive:

• Men should consider using condoms or abstaining from sex for at least 3 months after symptom onset or last exposure to minimize sexual transmission risk 5, 1

Travel Recommendations

• Pregnant women should avoid travel to areas with active Zika virus transmission 6
• Anyone traveling to or residing in areas with risk for Zika transmission is considered to have possible exposure 5

Treatment Approach

No specific antiviral therapy exists for Zika virus infection 2, 7

• Provide supportive care only: rest, fluids, and symptomatic treatment for fever and pain 2
• No vaccine is available, and development continues 2, 7

Pregnancy-Specific Considerations

Maternal-Fetal Transmission Risk

• Mother-to-child transmission occurs in 20-30% of maternal infections 7
• First-trimester infection carries the highest risk for structural birth defects 6
• Overall risk of structural birth defects ranges from 5-10% among infants born to mothers with confirmed or suspected Zika infection during pregnancy 6

Monitoring Requirements

• Prenatal ultrasound assessment is essential for monitoring fetal development and early detection of severe anomalies including microcephaly 7
• Most maternal infections are asymptomatic, making screening critical 7
• RT-PCR molecular methods are the most reliable diagnostic tool, as the virus persists in bloodstream for only a narrow window 7

Congenital Zika Syndrome

• Includes microcephaly, severe brain malformations, and Guillain-Barré syndrome 2, 3
• Even normocephalic infants with no observable birth defects at delivery may develop neurodevelopmental delays or postnatal microcephaly, requiring mid- and long-term follow-up 7

Common Pitfalls

• Underestimating viral persistence in semen: Zika virus RNA can be detected for months after infection, with 21% of men still positive at 61-90 days post-symptom onset 5, 1
• Failing to counsel about both mosquito AND sexual transmission prevention: Both routes require simultaneous attention 1
• Assuming asymptomatic infection means no risk: Most infections are asymptomatic or cause only mild symptoms, but fetal consequences can still be severe 2, 7