The nation’s top infectious disease doctor has warned that a second-wave coronavirus outbreak later this year is “inevitable.” Local experts say that means everyone will have to keep making sacrifices to slow the spread, even after society begins to reopen.

The extent of the virus’ resurgence this fall in Southern California will depend on people’s adherence to continued social distancing, as well as officials’ ability to identify and track cases, Dr. Barbara Ferrer, Los Angeles County’s top public health official, said Wednesday.

“As we’re all doing our part now, during recovery we have to do our part,” she said. “Nothing really changes in terms of the basics here,” which includes keeping 6 feet of distance in public, isolating yourself when sick and a continued focus on COVID-19 testing and patient contact tracing.

“Those still are our tools,” Ferrer said. “We just have to do it in a way that allows more people to get back to work — and that means there’s even more on each of us to do our part to keep our distance”

Both Dr. Anthony Fauci with the National Institutes of Health and state Gov. Gavin Newsom have said that lifting stay-at-home restrictions too soon could erase the their impact — and make the virus’ second wave worst than the first.

“If we don’t do that successfully, we could be in for a bad fall and a bad winter,” Fauci said Wednesday.

Experts worry the issue will be complicated by a simultaneous start to flu season, which also prompts an increase in hospitalizations.

“If you have been resistant against getting a flu shot, this would be the year to get your flu shots,” Ferrer said.

The sobering warning comes after state and county leaders indicated some restrictions will be eased in the coming weeks. Newsom on Tuesday released a four-stage plan reopening plan he expects will be underway by the middle of next month, while Ferrer said L.A. County currently has no plans to extend its stay-at-home order beyond May 15.

That’s even as the outbreak has yet to peak. L.A. County continues to see large number of virus-related fatalities and had an average of about 850 new cases reported each day over the past week. The county reported 56 more deaths Wednesday, accounting for nearly three quarters of the 78 new deaths statewide.

There are now a total of 22,485 confirmed coronavirus cases in L.A. County, resulting in 1,056 fatalities.

With the virus still spreading, Angelenos returning to beaches, trails and workplaces will have to “figure out how to do work in a different way that keeps us safe while letting us in fact get back to some normalcy in our lives,” Ferrer said.

If that doesn’t happen, we’ll see a spike, Ferrer added — especially considering that the vast majority of the population isn’t immune. A preliminary antibody study being conducted by USC estimated as many as 442,000 people in L.A. County caught the virus by early April — which would mean at least 96% of the population still hadn’t.

“There’s still a lot of infection that’s in our communities, and a lot of people who haven’t seen this infection and can still get infected,” Ferrer said.