The pooled option, which allows riders to book trips at lower prices by sharing the car with up to three other passengers traveling in the same direction, has been disabled for users opening the apps in the two countries.

“Our goal is to help flatten the curve on community spread in the cities we serve,” senior vice president Uber Rides and Platform Andrew Macdonald said in a statement.

A spokesman said similar steps outside the U.S. and Canada would be evaluated on a case-by-case basis.

Regular rides and the company’s food delivery platform Uber Eats remain available, but Uber said it was in contact with local authorities to adjust operations as needed.

North America provides the bulk of Uber’s revenue, but pooled rides make up only a small share of all bookings, data by U.S. cities showed.

Lyft Inc, Uber’s smaller North American competitor, on Monday did not respond to a request for comment on its shared rides policy.

The respiratory virus has spread quickly throughout the United States, killing at least 83 people as of Monday and infecting more than 4,600 Americans.

The White House on Monday urged people to avoid gatherings of more than 10 people and called for closing bars, restaurants and other venues in states where local virus transmission exists. Some state and local authorities independently imposed mandatory restrictions on those places.

Beginning on Tuesday, Uber users in the U.S. and Canada will also see a message reminding them to consider if the ride they plan to book is essential and to “travel only when necessary,” images provided by Uber showed.

Riders are also being asked to consider the safety of their drivers by washing their hands before and after a ride, sitting in the back seat and rolling down the window to improve ventilation.

Uber has previously said it will compensate drivers and delivery people diagnosed with coronavirus or placed in quarantine by health officials for up to 14 days.