BOSTON -- Fifteen Shrewsbury students and their chaperones have been quarantined in China after one student showed signs of the H1N1 influenza.

The students, who attend St. John's High School, were among 15 students and two chaperones who left the United States on June 11 on a school-sponsored trip to China.

One student was being monitored at a Beijing hospital and is expected to be released next week. Two students and a chaperone were quarantined in a Beijing hotel. School officials said that their quarantine period was expected to end at about 2 a.m. on Friday.

The other 12 students and a chaperone went on with their trip, but were later quarantined in a hotel in Shanghai.

"We anticipate their quarantine period will end early next week, if not sooner," the school said in a statement. "All students and chaperones in Shanghai are reportedly doing well."

Earlier this week, health officials announced that a 30-year-old Boston woman died from the H1N1 influenza.

There have been more than 1,100 cases of H1N1 in the Bay State since the start of the outbreak. Eighty of the cases required hospitalization, according to the Massachusetts Department of Public Health.

Many local schools continue to feel the brunt of the outbreak. The Carter Development Center and Louis Agassiz Elementary School in Boston remain closed.

"We expect that as the school year comes to an end across the commonwealth, we have issued guidance for schools as well as camps, where children are likely to be over the summer," said Dr. Lauren Smith, of State Health Department.

Department of Public Health Commissioner John Auerbach reassured residents that there is more than enough anti-viral medication for patients with influenza.

"We do know that influenza, for some people, causes serious illness. We expect that other people will be ill because of H1N1," Auerbach said.

Last week, the World Health Organization raised the worldwide pandemic alert level to Phase 6, which means that a global pandemic is under way.

NewsCenter 5 and TheBostonChannel.com will have more information when it becomes available.