SAN FRANCISCO (CBS SF) — While California has successfully “flattened the curve,” with Gov. Gavin Newsom saying the state projects a manageable peak of cases in May, that does not necessarily mean shelter-in-place orders will end come summer.

“We’re working really hard right now, trying to think about what would the signals be,” said Santa Clara County Health Officer  Dr. Sara Cody. “What do we need to have in place in order to relax a little bit? That planning is not just underway here in our county; this is what’s happening really across the world.”

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They are planning, but there is no firm answer yet. Even a flattened curve leaves Californians with the same problem the state faced on day one.

“We’re treading water until vaccine comes,” explained UCSF Epidemiologist George Rutherford. “How do we replace shelter in place until vaccine comes [in] 10 months, 11 months, something like that?”

Rutherford said while the state is doing well, it is also stuck. If the shelter-in-place and social distancing orders are lifted, the virus could could roar back, especially in the fall. As for the possibility of what is call “herd immunity,” that would require more than 70 percent of the population to have been infected.

Rutherford said that scenario was not only unlikely, but potentially dangerous.

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“With the intensive mortality rates that would bring, there’s nothing that’s going to protect the elderly if we try to get 70 percent of the population infected,” Rutherford said. “That’s not going to work.”

A perpetual lockdown won’t work either, so look for the summer to bring something in between: No baseball games with packed stadiums or crowded concerts, but maybe a return to business on the smaller scale, with ongoing precautions.

“Wearing masks in public,”  Rutherford cites as an example. “Maybe people who are older would be encouraged to stay home. Remember the governor’s proclamation of mid-March? Take some seats out of the bars, take every other stool out of the bar, that kind of stuff.”

That lighter lockdown would also require widespread testing and tracing to prevent new outbreaks from starting. Pick any sporting analogy, the challenge remains a long-term one.

“Think of this as three football games,”  Rutherford said. “It’s like the playoffs. So this is the first playoff game.”

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“I think that, in general, this incident is a marathon,”  Cody offered. “Maybe even an ultra marathon. It’s going to be a while.”