How does Zika virus spread?

The Zika virus is spread by Aedes species of mosquitoes. These mosquitoes can pick up the virus by biting an infected person, and then transmit it to someone else they bite later. The virus doesn’t typically spread from person to person directly, though sexual transmission is possible. In fact, the first case of local transmission in the mainland United States was a person who became infected after having sex with someone who had recently traveled from a country where Zika is present.

The type of mosquito that spreads Zika most often is limited to tropical and subtropical areas. In the US, they’re most common in Florida, the Gulf Coast and in Hawaii, but they also go as far north as Georgia and South Carolina. Another species that can carry them can range as far as New York in the summer. Experts think the virus will cause small, localized outbreaks in the US.

There is no vaccine to prevent Zika, so the best way to protect yourself is to avoid mosquito bites if you are in an area where Zika is active. The Centers for Disease Control and Prevention recommends that pregnant women avoid travel to countries where outbreaks are occurring, and also that they abstain from sex or use condoms with partners who have recently returned from one of these areas.

The World Health Organization recommends the following.

If you live in or travel to an area where Zika is common:

• Keep skin covered with with long-sleeved shirts, pants and hats.
• Use recommended insect repellants.
• Sleep under mosquito nets in topical areas.

To keep mosquitoes away from your home:

• Avoid allowing water to stand in outdoor containers.
• Put garbage in bags and closed containers.
• Use screens and mosquito nets in your windows and doors.