(CNN) The mayor of Los Angeles told CNN on Tuesday that residents shouldn't overreact to a top county health official's announcement that a stay-at-home order will stay in place for months.
Mayor Eric Garcetti told Anderson Cooper, "When our county health officer Dr. (Barbara) Ferrer merely said that an order would stay in place for at least three more months, that doesn't mean the order stays in place exactly as it is today."
Garcetti -- and Ferrer -- said restrictions on stores and public places will gradually be eased over time as health data shows it is possible. They also want treatment for coronavirus and testing to become more readily available.
The mayor said that some vulnerable population groups may have to continue to stay at home.
The extension of the stay-at-home order is "just a reminder of how delicate and fragile this time is, but do not freak out when you hear a scientist say that it's still going to be here and we're still going to be living under health orders," Garcetti added.
Earlier, he told CNN's Jake Tapper the needs for social distancing and wearing face coverings won't be going away in the near future.
"I think we know it's going to be even longer than three months. ... We're not moving past Covid-19, we're learning to live with it. We're not going to go back to pre-Covid life any time soon" or move forward without a medicine or vaccine, he said.
Ferrer, the health director of Los Angeles County, said at a Board of Supervisors virtual meeting that it was "with all certainty" that the county's stay-at-home will be extended from May 15 for three months.
The county has already modified some restrictions. Last week, some stores and outdoor spaces in the county were reopened with restrictions. Beaches open Wednesday for runners, swimmers and surfers, but not sunbathers.
Several big universities in the county, including Cal State Northridge and Cal State Long Beach, are among 23 schools in the state where in-person classrooms will be closed for the most part through the fall semester.
California State University System Chancellor Timothy White said exceptions will be made in some cases, such as nursing students. The schools have about 480,000 students.
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New York health officials are now investigating about 100 cases of an inflammatory illness in children that might be related to Covid-19, up from 73 last week, Gov. Andrew Cuomo said Tuesday.
The children had been hospitalized with a condition doctors described as "pediatric multisystem inflammatory syndrome."
The children had fever and symptoms similar to toxic shock syndrome and Kawasaki disease, the state has said. Kawasaki disease causes inflammation in the walls of blood vessels, including those that supply blood to the heart, which in rare cases can lead to deadly limitations in blood flow.
Three youths -- a teenager and a 5-year-old and a 7-year-old -- have died of the inflammatory illness, officials have said.
Medical experts said that immune treatments and blood thinners can help children affected by the syndrome.
A panel of pediatricians called the International PICU-COVID-19 Collaboration has compared notes and released a consensus statement defining the condition, named "Pediatric Multi-System Inflammatory Syndrome Potentially Associated with Covid-19."
"To date, most children affected have done well. Treatments have included anticoagulation, IV immunoglobulin, IL-1 or IL-6 blockade, and corticosteroids. Some children have only needed supportive care," Boston Children's Hospital said on its website.
New York has said many of its pediatric patients tested positive for Covid-19 or had its antibodies, but that they did not present with typical symptoms for the coronavirus disease. So health officials are investigating whether coronavirus presents a danger to children not previously understood.
The plurality of cases -- 29% -- involved children ages 5 to 9. About 28% of the patients were between 10 and 14, according to the state.
Similar reports of this syndrome in children have been made in Seattle; at Stanford Children's Hospital in California; and in the United Kingdom, Italy and Spain.
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More evidence is emerging that the virus was in the country earlier than initially thought.
The onset of five Covid-19 cases in five separate counties in Ohio happened as early as January, state Health Director Dr. Amy Acton has said, citing results of antibody testing.
"I think we'll see a lot more of this. I also think there are a lot of deaths and coroner reports yet to be seen, so I think as time goes on, we will learn more and more about history with this virus," Acton said Monday.
That meshes with a growing body of research suggesting the virus was spreading in the United States and elsewhere at least weeks, if not months, before official case counts started picking up in February and March.
Ohio will soon conduct 1,200 voluntary antibody tests to help it understand how many people already were infected without knowing it, Acton said. Some state and county governments, including Illinois' Cook County, have said they're reviewing deaths as far back as late last year to see whether they could be connected to the virus.
On Tuesday, the nation's top infectious disease expert warned senators of serious consequences for states reducing social distancing restrictions ahead of federally suggested milestones, even with the pandemic already having claimed more than 82,000 lives in the US.
Those milestones, which the White House recommended in mid-April, include a downward trajectory in virus cases for 14 days and a robust testing program in place for at-risk health care workers.
"If some areas, cities, states or what have you jump over those various checkpoints and prematurely open up without having the capability of being able to respond effectively and efficiently, my concern is that we will start to see little spikes that might turn into outbreaks," Fauci told the Senate Committee on Health, Education, Labor & Pensions.
The hearing was Democrats' first chance in weeks to question leading medical experts -- including Fauci and Centers for Disease Control and Prevention Director Robert Redfield -- about the Trump administration's response to the pandemic.
Witnesses made appearances remotely because they're self-isolating or self-quarantining after contact with people who tested positive for coronavirus.
Ahead of the testimony, 54% of Americans say the US government is doing a poor job preventing the spread of Covid-19, according to a new CNN poll.
Also, a vast majority of poll's respondents were "afraid" or "concerned" (35% and 46%, respectively) about the potential for a second wave of Covid-19 cases this year, while 18% were not concerned. Those two questions in the multi-topic poll -- conducted by phone Thursday through Sunday, with 1,112 adult Americans -- had a margin of error of +/- 3.7%.
So far, more than 1.35 million people have been infected in the US, while at least 81,571 have died. And the global death toll is approaching 300,000 reported deaths, according to Johns Hopkins University.
Some other developments from Tuesday's Senate panel hearing:
• Don't expect a vaccine in time for the start of the school year in the fall, Fauci said. That goes with what he's said previously about a vaccine: Maybe January at the earliest, and even that's pushing it. So, schools will have to rely on testing to help students feel safe enough to return, Fauci said.
• School reopenings will vary from region to region because "dynamics of the outbreak are different in different regions," Fauci said.
• The nation's actual death toll is likely higher than reported, Fauci said. He cited New York City, where the health care system was overwhelmed. "There may have been people who died at home (in that city) who did have ... Covid who are not counted as Covid because they never really got to the hospital."
• The US should have the capacity to produce, distribute and apply "at least 40 (million) to 50 million tests per month" by September, said Adm. Dr. Brett Giroir, assistant secretary for health at the Department of Health and Human Services.
The federal government has been under fire for the pace of the country's production of coronavirus tests. Public health experts say regular testing is critical to understanding the spread of the virus and to control it.
Last month, the Rockefeller Foundation argued the US should expand testing capacity to 3 million tests per week within the next two months, and expand capacity to 30 million tests per week over the next six months.