What is Zika (Zika virus)?

From the Guidelines

Zika virus transmission can be prevented by waiting at least 3 months after symptom onset or last possible exposure before engaging in unprotected sex, and using condoms or abstaining from sex to minimize the risk of sexual transmission. According to the Centers for Disease Control and Prevention (CDC) guidance updated in 2018 1, men with possible Zika virus exposure who are planning to conceive with their partner should wait for at least 3 months after symptom onset or their last possible Zika virus exposure before engaging in unprotected sex. Key points to consider in Zika virus prevention and management include:

• Zika virus is primarily transmitted through the bite of an infected Aedes aegypti mosquito, but can also be transmitted through unprotected sex with an infected partner 1
• The virus can cause severe birth defects, including microcephaly, and infection during pregnancy is a significant concern 1
• Prevention measures include using EPA-registered insect repellents, wearing protective clothing, and eliminating standing water where mosquitoes breed
• Sexual transmission can be minimized by using condoms or abstaining from sex for at least 3 months after symptom onset or last possible exposure 1
• The CDC provides updated guidance and recommendations for Zika virus prevention and management, including travel advisories and areas with risk for Zika virus transmission 1

From the Research

Zika Virus Transmission

• The primary route of Zika virus transmission is through the bite of an infected Aedes species mosquito, primarily Aedes aegypti 2, 3, 4, 5.
• Other routes of transmission include sexual activity, mother-to-fetus during pregnancy, mother-to-infant at delivery, laboratory exposure, and possibly transfusion of blood products 2, 3, 4.
• Zika virus can also be transmitted through sexual activity from an individual who is infected with the virus to their partners 2, 3.

Zika Virus Symptoms

• Most persons with Zika virus infection are asymptomatic or have only mild symptoms 2, 3, 4.
• When symptoms are present, they can include maculopapular rash, fever, arthralgia, and conjunctivitis 2, 3, 4.
• Less frequent symptoms include headache, vertigo, myalgia, vomiting, and diarrhea 3.
• Neurological complications can occur, including Guillain-Barré Syndrome (GBS), congenital ZIKV syndrome, acute myelitis, and meningoencephalitis 4.

Zika Virus Prevention and Treatment

• The primary methods of prevention include avoiding bites of infected Aedes mosquitoes and reducing the risk of sexual transmission 2, 3, 4.
• Pregnant women should not travel to areas with active Zika virus transmission, and men and women who are planning to conceive in the near future should consider avoiding nonessential travel to these areas 2.
• Condoms can reduce the risk of sexual transmission 2.
• Treatment is supportive, and no vaccine is currently available 2, 3, 4.
• Supportive care consisting of rest, hydration, analgesics, antihistamines, and antipyretics is recommended as needed 3.

Zika Virus Epidemiology

• Zika virus has spread rapidly, with active transmission reported in at least 61 countries and territories worldwide, including the United States 2.
• As of December 2023, there is documented evidence of current or prior autochthonous mosquito-borne ZIKV transmission in 92 countries and territories 5.
• Globally, cases declined after the height of ZIKV transmission in the Americas in 2015-2016; however, transmission continues across multiple regions, with intermittent outbreaks reported 5.