(Associated Press)

Major streets and highways were deserted in many parts of the world Saturday as curfews and lockdowns multiplied in the face of a rapidly advancing virus that is severely straining many health systems.

Three American states with a combined population of 70 million are moving to restrict residents to their homes. California started Friday and New York and Illinois were to follow this weekend. Connecticut and Oregon were preparing to do the same.

Once bustling outdoor plazas fell quiet in Bavaria after it became the first German state to tell people to stay home, except to go to work, buy food, visit the doctor or exercise. Colombia became the latest South American country to announce a lockdown, and Sri Lanka closed all expressways for a weekend curfew.

With hospitals already under pressure, officials in many countries are desperate to prevent — or at least limit — a repeat of what has happened in China and southern Europe. The coronavirus outbreak overwhelmed medical services in the central Chinese city of Wuhan earlier this year and now is pushing them to the limit in Italy and Spain. Britain has asked 65,000 retired nurses and doctors to return to work.

More than 275,000 cases have been confirmed globally, including more than 11,000 deaths, according to a running tally by Johns Hopkins University. At least 88,000 have recovered.

For most people, the new virus causes only mild or moderate symptoms, such as fever and cough. For some, especially older adults and people with existing health problems, it can cause more severe illness, including pneumonia. The vast majority recover.

The pandemic has moderated in Asia, with the concern shifting to preventing its return. China and other parts of the region are now importing cases from Europe, the U.S. and elsewhere.

China reported Saturday that its mainland had no new home-grown cases of the disease for the third straight day, but 41 imported ones in the previous 24-hour period. That followed a surge in cases in the territory of Hong Kong on Friday, including 35 imported ones.

Restrictions on movement are being eased gradually in China, as it tries to restart the economy without bringing back the disease.

Officials in Wuhan are permitting supermarkets, convenience stores and some other retail businesses to reopen from 9 a.m. to 6 p.m. if they are in areas with no confirmed or suspected cases. One person from each household is allowed to go out daily for a shopping trip of up to two hours.

The Beijing Zoo said its outdoor areas would reopen Monday, but visitors have to wear masks and make reservations at least one day in advance. Most major museums and attractions in China have been closed for nearly two months to stop the spread of the virus.

In the U.S., the restrictions on movement take effect Saturday in Illinois and Sunday in New York. All workers in nonessential businesses will be required to stay home and gatherings of any size are banned in New York. Exceptions will be made for important errands, such as buying groceries and medicine, and for exercise.

The lockdowns in California and other states sent stock markets tumbling again. Wall Street had its worst week since the 2008 financial crisis, with the Dow Jones Industrial Average falling more than 900 points and down 17% for the week.

BMW said it would shut down a huge manufacturing complex in South Carolina from April 3 to 19 and Nissan said it would suspend vehicle production at its two Mexican assembly plants from next Wednesday through April 14. Auto production has resumed in China, but only partially.

A member of Vice President Mike Pence’s staff has tested positive for the coronavirus, the White House said. A spokeswoman said the person did not have close contact with either Pence or President Donald Trump.

Colombian President Iván Duque announced Friday night that everyone would be required to isolate in their homes for three weeks starting Tuesday. The capital, Bogota, began its own lockdown Friday, leaving the city’s usually traffic-filled streets largely empty.

Colombia has 158 confirmed cases, and officials are hoping that drastic measures now will limit the number of new cases in the weeks ahead. Peru, Ecuador and Venezuela already are in lockdown.