Editor's note: This explainer was updated on Dec. 15, 2016, to reflect the latest information from federal and Texas officials.

With several locally transmitted cases of Zika identified in Texas, the Centers for Disease Control and Prevention is now urging pregnant women to avoid Brownsville. Health officials across the world are also still combating the virus.

Here's everything you need to know about the Zika threat in Texas.

What is Zika?

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Zika is a mosquito-borne virus. The virus is also transmitted sexually. Just 20 percent of people infected have symptoms, which can include fever, joint pain and rashes. It is not a fatal virus for most adults. But researchers have linked it to extreme complications in pregnancy. A pregnant woman with the Zika virus could give birth to a baby with microcephaly, a birth defect that causes abnormally small heads, blindness, behavioral delays and other neurological issues. Additionally, a small portion of Zika infections may cause Guillain-Barré syndrome, an illness that can result in paralysis. 

This isn't the first time there's been a Zika outbreak in the world, but it is certainly the largest. An earlier outbreak of Zika — which included fewer than 100 cases — was in 2007 in Micronesia. There was another outbreak in 2013, when there were nearly 20,000 suspected cases in French Polynesia. 

The current outbreak has affected more than an estimated 1 million people.

Is Zika widespread in Texas?

No.

According to the Centers for Disease Control and Prevention, there have been 268 cases of Zika in Texas. But most of the cases involved people who contracted the virus while traveling elsewhere. A few involved sexual transmission. Very few cases have involved people getting the virus locally from a mosquito.

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In August, a Harris County infant became the first Zika-related fatality in Texas. It was just the second death related to Zika in the continental United States after an elderly man died in Utah in June. 

Where are the other U.S. Zika cases?

So far, there have been 184 cases of locally acquired Zika virus transmissions in Florida. The CDC recommends that pregnant woman not travel to a 4.5-square mile area near Miami Beach. Like Texas, there have been travel-related cases all over the United States. The virus has spread to far more people — and caused much more damage — in Latin America.

What do I do if I think I have Zika?

If you haven't traveled to a country or place where the virus is prevalent, you probably don’t. The virus isn’t widespread in the United States yet, and certainly not in Texas. 

But if you are concerned, visit a doctor and get a blood test to confirm any diagnosis and discuss recovery options with your doctor. If you do have the virus — which is unlikely — there is no medication or Zika vaccine. The CDC recommends treating the symptoms, getting rest and drinking plenty of fluids.

Men who have the Zika virus should not have unprotected sex for six months after symptoms start because the virus can survive in semen. The CDC recommends that women with the Zika virus wait at least eight weeks after symptoms start before trying to become pregnant. 

What are lawmakers doing to combat Zika in Texas?

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Texas officials announced in August they would allow low-income pregnant women to pay for mosquito repellent with Medicaid. That benefit expired at the end of October, but the Texas Health and Human Services Commission reinstated it in November once officials announced they had found a locally-transmitted Zika case in Cameron County. Over the summer, Texas Gov. Greg Abbott and other Texas lawmakers urged the federal government to fund Zika prevention efforts. In September, Congress approved $1.1 billion to combat Zika across the country. Members of the Texas delegation praised the move, but some said it wasn't enough.

Even if there only a few cases so far, Zika is spreading via mosquitos in Texas. Now what?

Public health officials warned for months that it was possible that mosquito-to-human transmission of the Zika virus would eventually happen on a small scale in Texas. And after news broke of the Zika virus spreading in Florida, Texas officials said the Lone Star State was prepared. “This is exactly what we’ve been on alert for in Texas,” Carrie Williams, a spokeswoman for the Texas Department of State Health Services, said via email at the time. 

In mid-December, CDC Director Tom Frieden said the federal agency is working closely with the Texas Department of State Health Services and local officials to monitor cases and keep the public informed.

Some advocates have renewed calls for expanding Medicaid in light of the burgeoning public health crisis. They argue that low-income Texans are most vulnerable to Zika so expanding subsidized healthcare makes sense to ward off a possible public health emergency. But Medicaid expansion, long opposed by the state's Republican leaders, would be an uphill fight in Texas.

How can I learn more? 

On Oct. 18, we hosted a conversation about the Texas response to the Zika virus in Richardson. 

Panelists included state Rep. Myra Crownover, R-Denton, chairwoman of the House Public Health Committee; Christopher Frei, associate professor and division head for the Department of Pharmacotherapy at the University of Texas at Austin College of Pharmacy and a gubernatorial appointee to the Texas Task Force on Infectious Disease Preparedness and Response; Dr. Binh-Minh "Jade" Le, assistant professor of Internal Medicine at the University of Texas Southwestern Medical Center; and Zachary S. Thompson, director of Dallas County Health and Human Services. 

You can watch the video here

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