SAN JUAN, P.R. -- Puerto Rico is at risk of becoming the front-line of the battle against the spread of the Zika virus in the United States, and public health officials are bracing for thousands of cases in the coming months.
Dr. Jorge Muñoz-Jordán, the Chief of the Laboratory of Entomology and Ecology of the Dengue Branch of the U.S. Centers for Disease Control and Prevention in San Juan, Puerto Rico, is especially worried by the spread of Zika because the island has not been exposed to the virus in the past.
"Identifying the virus in the patients is very important because it will help doctors treat and identify the Zika patients," Muñoz-Jordán told NBC News correspondent Rehema Ellis. "It will also tell us, the health agencies, where the virus is circulating to provide control for the spread of the virus."
Since Zika was first detected in Puerto Rico on February 5, as many as 249 people have been diagnosed - 24 of whom are pregnant women. Muñoz-Jordán and his lab technicians test 250 blood samples every day of the week to track the spread.
"The presentation of the Zika illness is complex enough that it requires more than one test. You need to detect the virus at the beginning of symptoms, but you have to detect antibodies a few days after the symptoms," he said. "… Pretty much we're working seven days a week to determine whether our patients have Zika or not."
The Departamento de Salud, the health ministry on the island, is taking to Twitter to locate areas in which mosquitoes are reproducing. "Are there mosquito breeding sites in your community? Report it here," the Tweet reads.
The Department has also set up a Twitter handle just to inform the public about the Zika virus. The handle, @PRcontraelZIKA, details symptoms of the virus, where to spray insecticides and what to do if a person believes they have been infected.
Zulmarys Molina Paredes, 29, learned she had the virus just days after the first case was reported in Puerto Rico; she is one of the 24 expectant mothers in the CDC count. She went to a doctor February 8 exhibiting symptoms linked to the virus: rashes, red eyes and joint pain. She received a positive Zika diagnosis nine days later.
"When I got to the doctor's office, they confirmed it was Zika," she said.
She is four months into her pregnancy, and the Zika virus can cause microcephaly, a birth defect in which babies are born with small, underdeveloped brains and heads. So far, she is not worried for her unborn baby's health, and she goes to the hospital for regular sonograms.
She will not know definitively whether her unborn baby has been affected until her third trimester. For now, she protects herself by spraying her home with insect repellent so she does not contract another mosquito-borne illness.
"I'm doing my thing, I'm cleaning, I'm spraying myself here and at my job," she said. "I'm praying and I'm staying positive that nothing is going to happen, and also that my baby is going to be good."
The mosquito that spreads Zika also spreads dengue, chikungunya, and yellow fever throughout the world. Stephen Waterman, a researcher at the CDC's Division of Global Migration and Quarantine, said he expects there to be a Zika outbreak in Puerto Rico like the one in Brazil and other Latin American countries.
The CDC Laboratory of Entomology and Ecology of the Dengue Branch in San Juan is testing insecticides that would lower the mosquito population without harming pregnant women or their fetuses.
"We're studying whether the mosquitoes are resistant to the insecticide sprays that we hope to use around the houses of pregnant women," he said. "We need to make sure that the mosquitoes are actually killed by the insecticide because some mosquitos are resistant."
Waterman said up to 15 to 20 percent of Puerto Rico's population is at risk of contracting the virus, and that adds up to hundreds of thousands of people. Waterman said cruise ships and tourism to the island has the potential to bring Zika to states like Florida and Georgia.
"We have this mosquito that has spread throughout the world, particularly the tropical areas, but it is expanding its distribution," he said. "We really don't have great control of the tools yet. We're very close, but it's going to be very hard to control."
NBC's Rehema Ellis, Jane Derenowski and Patty Guerra contributed to the reporting of this story.