Paragraph: "As the spread of coronavirus has fed fears of illness, it has also spurred fears of mass quarantines. And looking at other countries that have been hit hard by the virus, including China and Italy, it’s not an idle question. On March 12, a reader sent us a comment from a website called Stop Mandatory Vaccination, run by a group that opposes bills to curb exemptions for vaccinations. (Here’s some background on the anti-vaccine movement.) The website said in part, ""The CDC can detain anyone with a fever — indefinitely. … Vaccination (is) a way people could get out of detention."" Similar comments on social media soon prompted high-level debunkings. Late on March 15, the National Security Council took to Twitter to knock down rumors about a national quarantine: ""Text message rumors of a national #quarantine are FAKE. There is no national lockdown. @CDCgov has and will continue to post the latest guidance on #COVID19. #coronavirus."" Text message rumors of a national #quarantine are FAKE. There is no national lockdown. @CDCgov has and will continue to post the latest guidance on #COVID19. #coronavirus Quarantines are real, but there’s a lot of misinformation floating around about the details. Here, we’ll attempt to clarify what’s accurate, and what’s not, about quarantines. (An inquiry to Stop Mandatory Vaccination was not returned.) There are two related terms that address this phenomenon: quarantine and isolation. ""Isolation"" separates people with a confirmed case of a communicable disease from people who are not sick. ""Quarantine"" separates and restricts the movement of people who were exposed to a contagious disease to see if they become sick. The last federal quarantine prior to the coronavirus outbreak came in the early 1960s, when officials were concerned about a smallpox outbreak. It’s been a century — back to the 1918-19 ""Spanish flu"" pandemic — since large-scale isolations and quarantines were last enforced. Federal quarantine power stems from Section 361 of the Public Health Service Act, which authorizes the Centers for Disease Control and Prevention to take measures to prevent the entry and spread of communicable diseases from foreign countries and between states. Federal regulations revised in 2017 allow the CDC ""to detain, medically examine, and release persons arriving into the United States and traveling between states who are suspected of carrying"" certain communicable diseases. (Here’s what a sample quarantine order looks like.) Those powers are carried out with help from other federal agencies, such as Customs and Border Protection and the Coast Guard. This federal government has exercised this power recently with travelers returning from locations where coronavirus has been spreading, based on presidential proclamations like this one. So far we’ve been referring to federal quarantines. But most quarantine power actually resides with state and local governments, as well as tribal law on tribal lands. That’s because federal quarantine powers are limited to persons entering the United States from elsewhere. By contrast, states and localities enforce those powers within their own borders ""CDC officials are ‘preparing as if (the new coronavirus) is the next pandemic,’ but in reality, the laboring oar falls to state and local health departments,"" Polly J. Price, a professor of law and global health at Emory University, has written in the Atlantic. So the assertion we’re checking in this article, by focusing on CDC, misses a lot of where the action is: state and local governments. Historically, forcible quarantines have been rare, and they require a court order. Most of the time, experts said, people who are infected are released on their own recognizance with a promise to self-quarantine. There’s judicial precedent for quarantine powers dating back to the early 1800s, but subsequent case law has required a degree of due process, especially given that a quarantine, unlike an arrest, involves the detention of someone who is not suspected of a crime. Past cases ""suggest that there are important limits on the ability of the U.S. and state and local governments when it comes to some types of public health action,"" said David Schultz, a professor of political science and legal studies at Hamline University. The government has to show real harm, as well as that people get due process and a chance to appeal. Becoming subject to forcible quarantines isn’t just a question of having a particular germ; it also requires a strong likelihood that you will spread it to other people. ""Since most people can take precautions, this typically only happens in the case of person who can’t stay away from other people,"" such as people who have a severe mental illness, said Wendy K. Mariner, a professor of health law at the Boston University School of Public Health. What if you refuse a mandatory order? Practical consequences for such an action are tricky. While fines and incarceration are allowed, no public health expert today recommends jailing a person unwilling to quarantine, because they would be introducing a contagion into a confined population. ""The likelier answer is hospitals with secure wards,"" Mariner said. Not any fever gets you quarantined, contrary to the assertion we’re checking. The government ""would have to have good evidence that the individual was exposed to COVID-19"" to impose a quarantine, said Lawrence O. Gostin, faculty director of Georgetown University's O'Neill Institute for National and Global Health Law. ""‘Fever’ is too broad a definition,"" Mariner agreed. In addition to coronavirus, the CDC is able to quarantine only for the following diseases: cholera, diphtheria, infectious tuberculosis, plague, smallpox, yellow fever, viral hemorrhagic fever, SARS and pandemic flu. It’s an exaggeration to say quarantine is ""indefinite"" detention by the government, especially given what we know so far about the course of coronavirus disease. First, as we noted, quarantine is usually self-regulated. And for those instances when it’s not, such as when an individual is uncooperative, the person is able to leave quarantine when they are no longer contagious. Vaccination doesn’t get you out of quarantine. Typically, vaccinations aren’t cures; they’re preventive measures. In any case, it’s moot for coronavirus, because there is no vaccine yet. Claims on the internet said ""the CDC can detain anyone with a fever — indefinitely. … Vaccination (is) a way people could get out of detention."" The CDC does have the power to isolate people with certain infectious diseases and quarantine those who had contact with an infected person. But this claim is wrong or misleading about many of the details. Most quarantine decisions will be up to states and localities, rather than the CDC. People can’t be quarantined for just having a fever; they have to be shown to have been exposed to a specific set of diseases. Most quarantines are done voluntarily, not by force of the state. And vaccination is not a ticket out of quarantine." Claim: “The CDC can detain anyone with a fever — indefinitely. … Vaccination (is) a way people could get out of detention.”