The STI Files: Zika

Stat: Zika virus disease (AKA Zika fever or sometimes simply "Zika," though that's technically the name for the virus, not the disease it causes) isn't officially classified as an STI, because sexual transmission isn't the primary route by which this virus is spread. However, the CDC and other health agencies have found that this newly emerging virus can be transmitted or acquired through some kinds of sex.

What is it exactly? Zika virus disease is caused by a virus in the family Flaviviridae, first isolated in Africa in 1947. From there, it spread slowly across the tropics, leading to an explosion of cases in 2015, when the virus first attracted international attention.

What are its symptoms? Many patients with Zika virus disease have few to no symptoms. Some people develop fever, joint pain, headaches, rash, muscle pain, and eye irritation, according to the CDC, but the vast majority recover from the infection without incident.

However, some patients later develop a neurological condition called Guillain-Barré Syndrome, where their immune systems begin attacking their nerves. Most patients recover, but in extreme cases, the condition can cause permanent nerve damage and even paralysis. Other patients have developed inflammation in their brains and spinal cords. Infection during pregnancy has been linked with neurological developmental anomalies, including a condition called microcephaly, in which an infant's head is unusually small. It can be difficult to determine if Zika infection has affected a pregnancy until around 24 weeks of pregnancy or even later — sometimes not even until the baby is born.

About how many people have it? Zika is an emerging virus, and as of August 2016, the World Health Agency was counting cases in the tens of thousands worldwide. It's statistically rare, but we don't know enough about the virus yet to determine exactly how rare it is.

How is it spread? This virus is carried by the Aedes mosquito, which likes to come out and play during the day, but isn't afraid to guest star at night, either. People of all genders can also transmit Zika sexually, through vaginal, anal, and/or oral sex, as well as by sharing sex toys. It can also spread transplacentally — a fancy way of saying that a pregnant person can pass the virus to the developing fetus.

How is it diagnosed? A patient's recent travel history, sexual activity, and symptoms can determine whether a doctor should order a blood test to look for signs of the virus. Even if you haven't traveled in an area with an active Zika outbreak, your doctor may be concerned if you had sex with someone who has, especially if they haven't been tested.

Is it treatable? No treatment is currently available, although some medications can manage symptoms like headaches and joint pain. Most patients recover on their own.

Is it curable? As of September 2016, Zika doesn't have a cure, and researchers are working on a vaccine.

Can it affect fertility? We don't know enough about Zika yet to know whether it affects fertility — but concerns about developmental anomalies are significant enough that pregnant people and those planning to get pregnant have been advised to exercise caution to prevent Zika infection.

What happens if you get Zika while pregnant? Research has linked infection to a number of neurological problems including microcephaly. Babies exposed to the virus in utero could have seizures, vision loss and hearing loss, difficulty swallowing, balance problems, developmental delays, and intellectual disabilities — they may require ongoing health care throughout their lives, and some may also need personal care attendants, aides, or part-time home health workers to help them manage tasks of daily living.

Can it cause death? Yes, but very rarely. Many of the Zika-related deaths on record occurred in people with preexisting medical conditions that likely complicated their situations.

How can we protect against it? When it comes to sexytimes, barriers, barriers, barriers! Condoms and dental dams are your friends. If you're using toys, don't share them unless you're using barriers with each partner and cleaning them between uses. If you're in an area with an active Zika outbreak, take precautions to protect yourself from mosquito bites, including wearing protective clothing, using mosquito repellant, and not diving headfirst into swimming pools filled with mosquitos.

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