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Zika Virus Infection Guidance, Tools and Resources

Zika virus infection

The Zika virus is a mosquito-borne flavivirus transmitted primarily by Aedes species mosquito (Aedes aegypti and Aedes Albopictus). These mosquitoes that are aggressive biters during the day but also bite at night.  An estimated 80% of persons infected with Zika virus have no symptoms.

Symptoms are usually mild and include acute onset of fever, and maculopapular rash, arthralgia, or conjunctivitis for several days to a week. Severe disease requiring hospitalization is uncommon and fatalities are rare. Currently, no vaccine or medication is available to prevent or treat Zika virus infection.

Outbreaks, cases and transmission

Zika outbreaks are occurring in multiple countries. In 2015, the first local Zika virus transmission in the Americas was reported in Brazil and local transmission has now been in several countries or territories in the Americas. (See world map and list of countriessopens in a new tab.)

Cases in the United States:

As of August 2, 2017 in US Territories, there have been more than 37,007 cases of Zika- the majority were locally acquired from mosquitos. In the US States, there have been 5,381 cases of Zika – the majority were travel-associated cases and 224 cases were locally acquired from mosquitos.


Travelers to areas with ongoing Zika virus transmission and outbreaks are at risk of becoming infected and spreading the virus to new areas.  The cases in Florida were not unexpected because imported cases may result in local spread of the virus in some areas where there are Aedes species mosquito. This happens when people infected with Zika virus infect mosquitoes that bite them and the mosquitos transmit the virus to others.

Clinicians- reporting, lab testing

A blood or urine test can confirm a Zika infection. Healthcare providers are encouraged to report suspected Zika virus disease cases to their state health department to facilitate diagnosis and to mitigate the risk of local transmission. CDC has provided guidance and training materials for clinicians and healthcare providers for evaluation, testing and clinical care of pregnant women, women of childbearing age, infants/children; guidance to prevent sexual transmission; and guidance for diagnostic testingsopens in a new tab.

Pregnant women

CDC is recommending that pregnant women consider postponing travel to any area where Zika virus transmission is ongoing. Pregnant women who do travel to these areas should talk to their doctors or other healthcare providers first and strictly follow steps to avoid mosquito bites during the trip. Women trying to become pregnant should consult with their healthcare providers before traveling to these areas and strictly follow steps to avoid mosquito bites during the trip and throughout the day, as the Aedes mosquitoes bite mostly during the daytime.

Key resources


CDC Health Advisories-Alerts


Location of Zika Infections

Traveler Health Precautions


Pregnant Women

About Zika Virus

Prevention of Sexual Transmission: Men and Their Partners

Mosquito Control

Hospital – Clinic Care Settings

Testing (blood, urine) and Diagnosis

Clinicians – Healthcare Providers


Response to Local Transmission


State and Local Public Health Laboratories

Blood Supply

Photo Credit: Muhammad Mahdi Karimsopens in a new tab Licensed under GNU Free Documentation License 1.2sopens in a new tab