Zika is a virus that is mainly spread by the bite of an infected mosquito, though other routes of infection are possible.
The Centers for Disease Control and Prevention (CDC) has an up-to-date world map showing areas with active Zika transmission.
Causes and Risk Factors of Zika Virus Infection
The Zika virus is spread primarily through the bites of infected Aedes mosquitoes (including the Aedes aegypti and Aedes albopictus species).
The mosquitoes become infected when they feed on someone who already has the virus, and they spread it to other people through their bites.
There are other, less common ways that the Zika virus may be spread. Some of these reported modes of transmission have not been confirmed or require more research. It is not spread by respiratory droplets like SARS-CoV-2, the coronavirus that causes COVID-19 infection.
Mother to Child
Zika can be transmitted from a mother to her baby during pregnancy or around the time of birth.
Blood Transfusion
Through Sex
Health officials have confirmed that the Zika virus can be sexually transmitted through unprotected vaginal, anal, and oral sex. The virus remains active in semen longer than in other bodily fluids such as blood and urine.
Laboratory and Healthcare Settings
There have been some reports of Zika virus infections acquired in laboratory settings.
Animals
Duration of Zika Virus Infection
Complications of Zika Virus Infection
Although most people recover from Zika within a week, there can be serious complications related to the virus.
Pregnancy and Zika
Pregnant women should take special precautions to protect themselves, because Zika virus infection has been linked to miscarriage and birth defects.
The CDC recommends that women who are pregnant or trying to become pregnant should consider postponing travel to areas where Zika is a concern. If expectant mothers must travel, they should talk to their doctor ahead of time and come up with a strategy to prevent exposure to mosquitoes and practice safe sex.
The CDC advises men who plan to conceive not to have unprotected sex for at least three months after any possible Zika exposure or symptoms since the virus can survive in semen for a prolonged period.
Microcephaly
Related Conditions of Zika
Guillain-Barré Syndrome
Several countries have reported increases in cases of Guillain-Barré syndrome (GBS) following Zika outbreaks.
Other Insect-Borne Diseases
Diseases Carried by Ticks, Mosquitoes, and Fleas Triple in the US
Just as alarming as the increase in known diseases is the fact that nine new germs spread by mosquitoes and ticks have been discovered in the United States and its territories since 2004. These include the Bourbon virus, a rare and deadly tick-borne disease that was first spotted in Bourbon County, Kansas, in 2014, and the Heartland virus, which is most likely transmitted by lone star ticks and is endemic to midwestern and southern states.
Resources We Love
Centers for Disease Control and Prevention (CDC)
The CDC offers science-based, data-driven info on Zika in the United States and abroad, including the basics about the virus, tips on prevention and mosquito control, and up-to-date maps and statistics.
World Health Organization (WHO)
The WHO directs and coordinates international health within the United Nations. Check out their website for comprehensive coverage of Zika, including fact sheets on the virus and associated conditions, updates on outbreaks, and answers to common questions.
National Institute of Allergy and Infectious and Diseases (NIAID)
Part of the National Institutes of Health, the NIAID undertakes and supports research into infectious, immunologic, and allergic diseases. On their website, you can find the latest news about treatment and vaccine research.
Additional reporting by Lynn Marks.
Editorial Sources and Fact-Checking
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