This article first appeared on The Washington Post.
The Zika virus has already killed more than 1,000 people in Brazil, according to the latest data.
That number is expected to increase to nearly 3,000 this week, according a Reuters tally.
But experts say the disease can also be passed through the air, and that some pregnant women may be exposed to the virus during pregnancy.
The new case is the first reported in the western hemisphere, but experts say there are many others out there.
Experts say that while there is no vaccine or vaccine-preventable measure to prevent Zika transmission, pregnant women who are infected should avoid being in close contact with people who may be infected.
So, what is the risk of transmission?
A virus that can spread through the respiratory system and gastrointestinal tract can remain in the body for days after a person is infected, said Dr. Eric Schmitt, a professor at the Johns Hopkins University School of Medicine and the director of the Johns Bloomberg School of Public Health.
That means if a person’s blood test for Zika indicates that they have the virus, they could be exposed.
And if that same person has the virus in the liver, kidneys or the intestines, that could result in a death.
The virus also can be transmitted through saliva.
The risk of passing Zika through the eyes is low, Schmitt said.
“If it’s not the eye, then it’s the nose, then the mouth,” he said.
The virus is also not transmitted through coughing or sneezing, but it can still be spread through contact with the body fluids that can be found in the respiratory tract.
“The respiratory fluids, especially if they’re the sweat, the saliva and the mucus that comes from the mouth, are the major vectors,” Schmitt explained.
“It’s very difficult to prevent transmission.”
It’s also not known whether Zika can spread from pregnant women to their unborn babies.
Experts say the virus does not affect fetuses.
What are the symptoms of Zika?
If you have symptoms, call your doctor.
If you don’t have symptoms or you’re worried you might have symptoms of the virus:Unexplained rash that gets progressively worse and has no clear cause, such as fever, sore throat, or chills, or that worsens when the symptoms last more than a day.
You’re likely to have a fever, chills or rash when you have Zika symptoms, but you may not feel them.
You may also notice that your fever has decreased.
A fever that’s higher than 95 degrees Fahrenheit, and is not accompanied by chills.
A rash or bleeding that appears on the face or body and is usually painless.
If the rash or pain is not relieved by medical treatment, call 911 or go to the nearest emergency room.
In addition, a rash that develops when the person has traveled to another country and has symptoms of infection is called microcephaly.
A condition in which the brain appears abnormally small, and a child has microcephalus.
The symptoms of microcephelus include weakness and memory loss, difficulty walking, difficulty swallowing and coordination problems.
The disease can be caused by a virus or bacteria that infects a person or is transmitted through direct contact with a person with the virus.
Symptoms can also occur when the virus spreads from person to person.
In severe cases, the virus can cause brain damage and even death.
The National Institute of Allergy and Infectious Diseases estimates that at least one out of every five cases of Zika infection in the U.S. will result in an unborn child becoming infected.
But experts say Zika has not yet been found to be transmitted to fetuses, or to children.
So what should pregnant women do?
It’s important to discuss the Zika virus with your doctor before beginning any prenatal care, and during the first trimester, if you have questions about pregnancy or birth control.
But it’s also important to know that there are other precautions, such a full screening for other infections, that can help prevent Zika.