Dozens of Boston Marathon runners were felled by illness in the unusual heat today as temperatures rose by midafternoon to 87 in Boston, breaking the previous record for the day. Temperatures were even higher inland, where runners began the 26.2-mile trek to the city.
About 50 people had been taken to hospitals by ambulance as of about 3:30 p.m., said Kurt Schwartz, director of the Massachusetts Emergency Management Agency. He said other people may have admitted themselves.
He said one runner had suffered a potentially serious injury in Wellesley but declined to comment further.
Schwartz said about 800 people had sought assistance from medical staff along the course, though he could not say why they sought treatment.
He said that at one point Leonard Morse Hospital in Natick went on diversion for about an hour, during which time its emergency room was not able to admit more patients.
The bulk of the medical issues began to arise in Wellesley. There were also problems in Newton and Brookline, Schwartz said.
Race officials said that while medical tents were operating at or near capacity, medical staffers were not overwhelmed because they had planned for an influx after seeing the hot forecast.
“It is a very busy day, but it is the busy day for which people planned,” said the Boston Athletic Association's executive director, Tom Grilk.
Jack Fleming, a BAA spokesman, said the highest temperature recorded for the day was 89 degrees at the 10-kilometer mark in Framingham at about 12:30 p.m.
Fleming said 3,863 people did not pick up their numbers over the weekend to race, or about 14 percent of the field. He said about 9 percent do not pick up their numbers in a typical year.
Fleming said that of the 22,426 runners who did pick up their numbers, 427 opted to defer for a year. A deferment was also offered in 2010, he said, when volcanic ash made it difficult for some people to fly in from overseas. About 350 people chose deferments that year.
At Newton-Wellesley Hospital, shortly before 3:30 p.m., at least 40 people had been treated for heat-related injuries. All the illnesses were routine, such as dehydration and faintness, but medical personnel were closely watching one middle-aged man, said hospital spokesman Brian O’Dea.
Framingham’s deputy fire chief, Richard Garvey, said his department had taken about 22 people, mostly runners, to hospitals.
“They were showing signs of heat exhaustion, dehydration,” he said. “Nothing that we believe is life-threatening.” Runners also suffered a couple of orthopedic injuries. He said that because of the number of calls the department was receiving, he had triggered an emergency system and got help from the District 13 ambulance task force, which added four ambulances to the department’s five. He even called in the help of four vehicles from Springfield and six from a private company.
Jennifer Mehigan, a spokeswoman for Boston Emergency Medical Services, said, “I do know that lot of runners [were] having issues as early as Framingham and Natick.”
At Newton-Wellesley Hospital, which is along the marathon route, a triage tent was set up. At one point, a runner jogged to the sidewalk and leaned on an electric pole, exhausted. Spectators gathered around, asking if he needed help.
Anke Preiss, visiting from Germany, poured water on his shoulder. “I was just trying to help,” she said.
The man recovered quickly and took off running.
The marathon course runs from Hopkinton west of Boston to the city’s downtown. In the interior of the state, temperatures were sizzling in the middle to high 80s and in some places 90, according to the National Weather Service.
The 87 degrees in Boston recorded at 2:42 p.m. was higher than the previous record of 84 in 2003.