In Maine, one inhabited island tried to keep people from coming over from the mainland because of contagion concern; on a nearby island, several residents cut down trees to blockade a house occupied by people feared to be infected by COVID-19. Some states are stopping incoming cars based on their license plates; others are “suggesting” or “requiring” 14-day quarantines, but with no enforcement. All of this is in the context of no nationally mandated restrictions on movement within the U.S. in the face of a fast-spreading virus that knows no borders.

With almost 500,000 “confirmed” cases of infection in the United States and more than 18,000 deaths, one of the surprises has been how little experienced lawyers and government officials seem to know about what are limits of the law to more quickly flatten curves and reduce the exposure of healthy people to those who are infected but asymptomatic.

Can the constitutional right to interstate travel and commerce be limited in a time of a public health emergency? Likewise, few have answers for how local and state governments can either act on their own initiative without running afoul of federal law, or how federal officials could act more proactively based on existing laws and regulations.

COVID-19 is not the first pandemic affecting America, and will not be the last. One federal law authorizes the surgeon general – who has said this week will be our new Pearl Harbor or 9/11 in terms of deaths – to make and enforce regulations “necessary to prevent the introduction, transmission, or spread of communicable diseases from foreign countries into the States or possessions, or from one State or possession into any other State or possession.”

And following the Ebola crisis of just three years ago, such federal regulations exist – but are not being applied, and must be strengthened on an emergency basis. One authorizes the apprehension, examination and detention “of any individual reasonably believed to be infected with a communicable disease and (A) to be moving or about to move from a State to another State; or (B) to be a probable source of infection to individuals who, while infected with such disease in a qualifying stage, will be moving from a State to another State.”

Another 2017 federal regulation also authorizes that if the Centers for Disease Control and Prevention director “determines that the measures taken by health authorities of any State or possession (including political subdivisions thereof) are insufficient to prevent the spread of any of the communicable diseases from such State or possession to any other State or possession, he/she may take such measures to prevent such spread of the diseases as he/she deems reasonably necessary.” A related regulation then provides that the CDC Director “may authorize the apprehension, medical examination, quarantine, isolation, or conditional release of any individual” reasonably believed to be infected.

Can’t the government do more than just try to identify and detain 2020’s equivalents of Mary Mallon – the cook who, in the early 1900s, infected 51 people with typhoid while she herself was asymptomatic? Yes, it can and must, especially in the face of states that either believe they are powerless to stop anyone from coming across state lines, or whose governors still do not see sufficient need.

Currently the U.S. is precluding people from multiple countries that had early COVID outbreaks from entering the 50 states. But with America now leading the world in COVID cases and very soon in deaths as well, it is urgent that Congress – this week – enact and the president sign legislation that likewise restricts people from crossing state borders within the 50 states until the CDC director declares that the public health emergency is over.

States can restrict the entry of diseased animals from another state; our current COVID pandemic requires that we humans also have our right to interstate travel, to sit in crowded sports arenas or to dine in restaurants, restricted as well. Otherwise, thousands of Mary Mallons will be unknowingly putting at risk many thousands more of their fellow Americans.