With back-to-school season just around the corner, federal health and education officials today are not suggesting drastic K-12 schools closures where students have already caught swine flu.
Instead they're releasing guidance for schools that outlines what schools can do while keeping doors open -- and have loosened their recommendation for the amount of time sick students and teachers should stay home.
If the flu does not get any more severe, the advice is for those sick with swine flu to stay home just 24 hours after their fever subsides and they are off of fever medications rather than holing up for seven days as previously instructed, Thomas Frieden, director of the Centers for Disease Control and Prevention, said today.
"We are relying on the science for the guidance we are providing," added Homeland Security Secretary Janet Napolitano.
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Still, there is a list of specific advice for preventing the spread of the virus while learning continues.
"Ill students and staff should be separated and given protected gear such as a mask until they can leave the school," Napolitano said. "Hand washing and cough covering are essential."
Today Kim Dockery, assistant superintendant at Fairfax County Schools in Virginia, told ABC News that part of that school system's plan is to teach a health curriculum to students in the first two weeks of the school year that stresses those very tips.
Dockery said that's just one of several preparations underway, including bringing in masks and more hand sanitizer.
"We're preparing online resources so that parents can access materials if kids are out," she said. "We're also preparing principals and schools to be flexible and be able to respond to whatever situation might come up. We don't know the severity of the disease, we don't know how much vaccine will be available, so we're planning a lot of eventualities."
Advocating "prevention, close monitoring and common sense," Education Secretary Arne Duncan, the father of a second grader and a kindergartener, said it's also a good idea to think about how to keep sick kids engaged from home, whether by considering temporary home schooling, or lessons via phone and the internet. Duncan also suggested there be a room set aside at schools where sick kids can go until they head home.
The secretaries added that ultimately decisions must balance the disruptions caused at school with the risk of swine flu spreading -- and those decisions must be made locally.
They added that schools for pregnant teenagers, students with medical conditions and other vulnerable populations should consider taking more stringent measures and more seriously consider closing schools.
If and only if the swine flu virus takes a more deadly turn, they said all K-12 schools should consider more dramatic measures, like actively checking students and staff for fever, moving desks farther apart in that case, and staying home longer to prevent swine flu's spread.
Meantime, only 45 percent of schools have a full-time nurse and a quarter of schools don't have one at all, according to the National Association of School Nurses.
So far, however, they are confident there's no need for panic.
"What we are seeing looks very much like seasonal flu so far," Health and Human Services Secretary Kathleen Sebelius said.
Today's guidelines for K-12 schools will be followed in the weeks ahead by guidelines specific to colleges, day care facilities and employers.
Visit the ABC News OnCall+ Swine Flu Center to get all your questions answered.
Government recommendations on swine flu preparations and prevention can also be accessed at www.flu.gov.
U.S. Clinical Trials To Start Today
Today the first three of thousands of volunteers also begin clinical trials in Seattle so health officials can learn more about whether the immunization shots are safe.
Tests also start Monday at the University of Maryland, Children's Hospital in Cincinnati and Emory University.
The test centers in the United States have been flooded with volunteers to try out the vaccine. The U.S. government alone wants nearly 160 million Americans to be vaccinated, and students are among the first in line. Also on the priority list are pregnant women, people who care for infants under 6 months of age, health care and EMS workers, and anyone under the age of 64 with underlying medical conditions.
Two shots of the swine flu vaccine -- in addition to one shot for the regular seasonal flu -- are expected to be administered to protect people.
"Young adults haven't seen it before," said Dr. William Schaffner, a volunteer in the clinical trials and professor and chairman of the department of preventive medicine at Vanderbilt University School of Medicine in Nashville, Tenn. "You need the first shot to get things going and then the second as a kind of booster that will actually give you complete protection," he added.
The results of this month's clinical trials in the U.S. are expected at the end of September. It could take another four to six weeks from that time to begin a vaccination program, pushing the start of the nation's voluntary vaccination program into November.
That could mean a two-shot series, with shots likely given about three weeks apart, may not bring full immunity against the swine flu virus until December.
"We first recommend that people who are ready and willing to get a seasonal flu vaccine do that quickly," Sebelius said today.
Today health officials also said it would make sense to designate schools as places where vaccinations take place. Duncan said he met yesterday with school boards and teachers associations who are receptive to that plan.
The government's school guidelines released today come in response to extensive school closings last spring when swine flu first surfaced.
In May, the Obama administration urged schools to shut down to stop the spread of swine flu, and hundreds did -- affecting half a million students. But within weeks, the CDC revised its lesson plan.
"In the spring, we had much less information about H1N1 than we have today," said Frieden, who was health commissioner in New York City at the time.
"Once you close a school, as we saw last spring, that causes a very significant ripple effect. We do not want kids going to the mall or anywhere else," Napolitano said. "The whole point is to reduce transmission."
ABC News' Dan Childs contributed to this report.