Mary Pappas, a nurse at New York City's St. Francis Prep High School, has a tip for teachers, students, parents and employers preparing for a possible resurgence of swine flu this fall: Teamwork.
Pappas sent 102 children home sick this spring when St. Francis faced its own outbreak. As lines of students snaked through her office, Pappas tapped security guards to lend a hand.
"They helped," she said. "I taught them quickly how to take temperature, and they took temperatures, and put it on a Post-It note, and stuck it on the child."
Teamwork was also the theme of today's swine flu summit, where federal, state and local health officials gathered to size up what needs to happen to prepare for and prevent a second round of swine flu illnesses at the beginning of the upcoming school year like the ones that hit the world this spring.
President Barack Obama this morning called from Italy to urge the group gathered at the National Institutes of Health in Maryland to prepare now for a fall vaccination program.
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"We want to make sure that we are not promoting panic, but we are promoting vigilance and preparation," Obama said.
Having studied other public health challenges, he said, the president's team is well-prepared for whatever scenario lies ahead but touted local rather than federal efforts as key to curbing the spread of the virus.
"Where it's well-handled, state and local officials have complete ownership over this issue," Obama said. "They are providing good ideas to the federal government. They are critical links to inform us what's working and what's not."
A big part of preparing for a fall outbreak is developing a vaccine to fight this flu. The government today said clinical trials will start in August, with a voluntary vaccine program anticipated to begin in mid-October.
That vaccine program would be limited at first to those most susceptible to the virus. Those first in line to receive the series of two shots would be children, teenagers, health workers and pregnant women. Vaccine would be purchased by the federal government and distributed to state and local health departments.
"Right now the virus strain is being grown," said Health and Human Services Secretary Kathleen Sebelius. "We'll begin clinical trials this summer. We'll know more by, I think, the end of August."
"Even though we can't definitely say we know exactly what's going to happen, I would be terribly surprised if September and October came and all of a sudden this virus disappears because it's still hanging around in the northern hemisphere, and it's acting like a seasonal flu in the season of flu in the southern hemisphere," said Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases.
Sebelius called on all states to update their emergency plans, including ways to carry out a mass vaccination program.
About $350 million in grants will also be divvied up among all states and U.S. territories, Sebelius said. About $260 million of that money will go to state health departments to prepare for vaccines, and $90 million will be funneled to hospitals to prepare for a surge of patients.
"Preparation is key," said Homeland Security Secretary Janet Napolitano. "You've got to be thinking, and we all are thinking, about nuts-and-bolts types of questions."
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Since this spring, more than 94,000 people worldwide have fallen ill from swine flu and 429 have died from the virus, according to the latest numbers released this week from the World Health Organization. By comparison, about 250,000 people worldwide die from the seasonal flu every year.
Swine flu was declared a pandemic June 11, reflecting the continued spread of the virus around the globe as opposed to its severity.
But Sebelius said despite concerns, the outbreak "also brought a valuable opportunity: The attention being paid to the H1N1 virus is accelerating our work to improve the entire public health system."
Sebelius said it's everyone's responsibility to get the word out to curb the spread of swine flu. Today she invited people today to submit their own 60-second swine flu public service announcements, dubbing the effort the "YouTube challenge." The winner's PSA will be aired nationwide.
With teenagers especially at risk for this flu strain, the Health and Human Services Department is also turning to social networking sites like Twitter and Facebook to communicate.
"It's a responsibility that we all share as parents, neighbors, co-workers and community members," she said.
"We want to start reengaging the American public and our state and local and health and private business partners in making sure we use these summer months well to prepare for what could be a serious outbreak," Sebelius said. "If it doesn't happen, we'll be fortunate and this planning won't go to waste."
Youth have been hard hit in the swine flu outbreak, making school district preparation key in prevention efforts.
At the height of the outbreak one day in May, 726 schools were closed in the United States, Education Secretary Arne Duncan said today.
Should that happen again in the fall, Duncan said today, "Whether it's for a day or week or month, again it's critically important for me that learning continues."
Meantime, a total of $1 billion has been appropriated to buy bulk ingredients to produce a vaccine.
Health officials are also keeping an eye on reports of resistance to the antiviral Tamiflu, a drug used to prevent and treat influenza
Dr. Thomas Frieden, director of the Centers for Disease Control and Prevention, told ABC News today that there are three "isolated cases" around the world of resistance to Tamiflu.
"These three individual cases are not worrisome in themselves," infectious disease specialist Christopher Ohl said today. "It doesn't look like the virus spread to another person, so it seems to be contained."
Still, Ohl said, "The problem is that Tamiflu's been the main drug that all across the world we've been stockpiling for use in the pandemic. If it becomes resistant and that drug is not available, then we'll have to turn to an alternative."
"We're anxiously anticipating actually the arrival of the vaccine," Ohl added. "In order to make a real impact on the number of cases that we have and to try to prevent more severe cases of H1N1 pandemic influenza, the real only way to do it is to have a good vaccine for it."
ABC News' Dan Childs contributed to this report.