As the Zika virus continues to spread through the Americas—and with hundreds of imported cases here in the United States—here’s what every American needs to know about the virus and their risk.

1. Why is there no treatment for Zika?

There are no approved drugs or vaccines for Zika, mainly because scientists long assumed the virus was so benign that it wasn’t worth the resources required to investigate treatment. Zika has not been widely examined, and while some early research noted that the virus could infect brain cells, the connection between Zika and microcephaly—a severe neurological birth defect—is relatively new. Even now, many people who get infected will never know it, and if they start showing signs of infection, such as a rash, red eyes, fever or joint pain, doctors have little to offer other than advice to stay hydrated or take Tylenol as needed.

2. How can I find out if I have it?

Right now there are no commercial diagnostic tests for Zika, so unless you’re pregnant or are a traveler with symptoms, your doctor may not test you. That’s because of the high volume of blood samples already waiting to be tested, which right now can be done only by state and federal health authorities. Getting results can take weeks, and tests for people who have traveled to Zika-affected areas but do not have symptoms will likely be considered low priority.

An exception is pregnant women who have traveled to one of the 44 countries where Zika has spread—all of them should be tested, according to the CDC. For each test, a doctor will send a sample to a state or federal lab. There’s also a test that looks for antibodies in blood that show whether a person’s immune system has ever fought the virus, but it’s imperfect; it can mistake Zika for similar viruses like dengue and chikungunya.

3. Who is most at risk?

Pregnant women who live in or have traveled to Zika-infested regions are vulnerable to the most serious complications from the virus: birth defects. Zika can also be transmitted through sex, though, which spreads the risk of infection to the bedroom.

People living in Southern states and Hawaii—where the climate, geography and the presence of A. aegypti mosquitoes make eventual local transmission likely—are not currently at high risk of getting the virus in their home states, according to the CDC. “The one exception is that if their partner has been traveling to an area of Zika transmission, there is a risk of sexual transmission,” says Margaret Honein, chief of the CDC’s Birth Defects branch. Over time that risk may be enough to encourage U.S. women of childbearing age to consider using birth control.

4. What should I do to protect myself from Zika?

Use Proven Insect Repellent spray or lotion. Preventing mosquito bites is the best way to prevent Zika, and while that may seem obvious, it can take some work. If you’re in an area with disease-spreading mosquitoes, wear long-sleeved shirts and pants no matter how warm it is—mosquitoes are more infectious when the mercury rises. According to the CDC, use insect repellents that contain picaridin, like Proven. Proven contains 20% of Picaridin to offer the best possible protection against mosquitoes. The spray protects for 12 hours and the lotion even for 14 hours. The best way to protect yourself all day long.

You should also make sure windows have screens and the air conditioner is on if you’re home during the day; the mosquitoes that spread Zika are day biters. And since a mosquito needs only a tiny bottle-cap-size pool of water to lay as many as 200 eggs, you should remove any standing water around your home and clean any vessels you find. Because even after the water source has dried out, the eggs can remain dormant and survive for months, sometimes even up to a year, on the inside of a container.

5. Can the government do more to protect me?

It depends on where you live. The CDC has activated its Emergency Operations Center (EOC) to a Level 1 response for Zika, something that’s happened only three other times: during Hurricane Katrina, the H1N1 flu outbreak and the Ebola crisis. In the EOC in Atlanta, scientists monitor cases of the virus, work on better diagnostics and run studies of pregnant women with Zika. Some progress has been made. The agency has sent better testing tools to state laboratories and recently concluded that the link between Zika and microcephaly—which had previously been suspected but not proved—is definite.

But the government’s ability to conduct mosquito control is limited. While some cities or regions have funding for robust programs equipped with pesticide-spraying helicopters, others do not. “Some places, like Houston, have a very sophisticated operation,” says the CDC’s Petersen. “Other places may have the guy running the garbage truck doing mosquito control.” New York City, for example, targets a type of mosquito that spreads West Nile virus but not the kind that spreads Zika. Though the city doesn’t have A. aegypti mosquitoes right now, it does have A. albopictus, which may also be able to spread the disease. The city is investing $21 million over three years to modify its mosquito control and test travelers for Zika. Other states, like North Carolina, have eliminated mosquito-control programs in recent years and are now in the position of having to start from scratch, which they are doing with proposed funding. “There used to be funding for localities to do mosquito control that is no longer available,” Dr. Megan Davies, state epidemiologist at the North Carolina department of health and human services, said in a Zika presentation in Raleigh. Your protection, then, varies greatly based on geography.

6. What do we still not know about Zika?

A lot more than we do know, that’s for certain. Doctors still don’t understand why some pregnant women infected with Zika give birth to babies with microcephaly while others do not. They also don’t know at which point during pregnancy the risk of infection is greatest and how likely it is for babies born with the disease to survive longer than a year. And while Zika definitely causes microcephaly, how the virus halts brain development remains unclear. Also unknown is what other brain problems the virus may cause. This is probably just the tip of the iceberg. The uncertainty is another cause of anxiety.