As the number of coronavirus cases grows in the U.S., we’re hearing a lot about how social distancing, self-monitoring and even quarantine play into containment efforts.

But what do those terms mean and when do they apply?

We asked experts and found out there is some overlap and lots of confusion.

Here’s a quick guide for what you need to know.

Q: Why is all this happening?

In the U.S., testing got off to a slow start, limiting efforts to isolate those with the disease. Public health experts now say the most important goal is to slow the spread of the coronavirus so that the number of people who require medical attention doesn’t overwhelm hospitals.

If evidence holds from experiences to date in countries further along in the outbreak, most people who contract this virus will have mild cases. Still, the data from abroad indicates that 10% to 20% could end up in a more serious condition. That means if tens of millions of Americans come down with COVID-19, potentially hundreds of thousands may need hospital care.

No one wants that to happen.

“That could stress the health system. We’re trying to avoid becoming like Italy,” said Joshua Sharfstein, vice dean for Public Health Practice and Community Engagement at the Johns Hopkins Bloomberg School of Public Health in Baltimore.

In Italy, the number of cases rapidly skyrocketed from a handful a few weeks ago to nearly 28,000 cases and more than 2,100 deaths as of Monday afternoon. The rapid escalation may be partly attributed to aggressive testing, but hospitals in the northern part of the country are running out of ICU beds.

Q: What is the difference between self-quarantining and self-monitoring?

There’s a bit of overlap, say experts.

Both strategies aim to keep people who have been exposed, or might have been exposed, away from others as much as possible for a period. That has generally meant 14 days, considered the incubation period of COVID-19, although symptoms can appear within a few days of exposure.

Self-monitoring might include regularly checking temperature and watching for signs of a respiratory illness, such as fever, cough or shortness of breath, according to the Centers for Disease Control and Prevention. It also involves limiting interaction with others.

Say, you attended a large conference where someone was later found to be positive for the coronavirus, even if you were not in close contact with that person. “The person speaking at the podium was later diagnosed and you were in the audience ? you’re not considered at risk. Those people may want to strictly self-monitor,” said Dr. Marcus Plescia, chief medical officer for the Association of State and Territorial Health Officials.

“But if you had a long conversation [with that person] or that person coughed or sneezed on you, that’s different,” he added. You “would then self-quarantine.”

Self-quarantine is a step up from self-monitoring because the person at risk of infection — even though they still don’t have symptoms ? had a higher chance of exposure.

Canadian Prime Minister Justin Trudeau, for example, is self-quarantining because his wife tested positive for the virus after returning from a trip to Great Britain.

Quarantining means staying home and away from other people as much as possible for that 14-day period. People in this circumstance who don’t live alone should do their best to retreat to their room or find a separate area in their home, and don’t go out shopping, eating or socializing.

“Don’t sleep in the same bedroom [with other family members] and try to use a separate toilet, if you can,” said Dr. Georges Benjamin, executive director of the American Public Health Association. “Be careful with dishes. They should go right from you into the dishwasher.”

If you are under a self-quarantine because of possible exposure, then develop a fever, cough or shortness of breath, call your doctor, local hospital or public health department to find out what to do. Some insurers and hospitals systems have online or phone assessment programs. For mild cases, physicians may direct you to stay home and treat your symptoms with over-the-counter fever reducers and other treatments. Those with more serious symptoms and people in higher-risk groups may be directed where to seek medical care.

As test kits become more available, you may also be directed to a place where you can get one.

Q: What does isolation mean?

A diagnosis of COVID-19 triggers isolation.

“Isolation is when you are sick, either at home or in the hospital,” said Benjamin. “Infectious disease precautions are then much more rigid than in self-quarantine.”

Medical staff, for example, wear gear that is more protective. In addition, the person in isolation would be asked to wear a mask when leaving their room or traveling from home to a medical facility —to try to prevent spreading droplets that might contain the virus.

Q: What is a quarantine?

This is when ? under state or federal law — individuals or groups are essentially on lockdown. Recent examples include passengers from cruise ships where passengers fell ill with COVID-19 and were then required to stay at military bases for 14 days to see if they developed the disease.

The U.S. hasn’t closed off entire areas ? such as towns or cities — since the “Spanish flu” of 1918-19. But the federal government and the states do have the power to do so.

In New Rochelle, New York, officials have established a “containment zone,” because of a high number of COVID-19 cases in the region. School and houses of worship are closed and large gatherings barred. But it is not considered a quarantine because people can come and go.

Q: OK, I’m not sick or exposed. What else can I do? What is social distancing?

This is a broad category. It means not shaking hands, standing several feet from other people and avoiding crowds. And, most important, staying home if you feel sick.

Businesses are doing it when they ask employees to work from home or stagger work hours. Government is doing it when they close schools. We’re seeing it in the sports world, with no-spectator games or the postponement of sporting events. Museums, theaters and concert halls where large groups of people gather are closing their doors.

It means trying to find the least-crowded train car or possibly driving instead of taking mass transit.

“It’s about taking stock, how closely you interact with people in day-to-day life,” said Christopher Mores, a professor in the department of global health at the Milken Institute School of Public Health at George Washington University. “Increase distances. Cut out handshakes. The idea is to try to empower people to break the lines of transmission.”

Q: Why should I care if I don’t think I’ll get very sick?

Public health is all about the public. Individual risk may be low. And, thus, the inconvenience of some of these measures may seem high. But taking steps like these will benefit the population as a whole, said Sharfstein.

“An individual who doesn’t get very sick might still pass the infection along to others, including parents, neighbors, people on the bus,” he noted.

Some of those people, in turn, may end up in the hospital. A surge of patients with the virus could fill beds also needed by a broad range of others, such as cancer patients, newborns or car accident victims.

“This is a condition that may not pose a threat to the individual, but a threat to the community,” warned Sharfstein.