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Last Updated

23 Apr 2003

Source: New York Times, April 23, 2003


Health Officials Seek Help From U.S. to Control Virus


Canadian health officials, concerned about the continued spread of the illness known as SARS among health care workers and new studies suggesting that the virus can survive on objects for 24 hours, have asked experts from the United States Centers for Disease Control and Prevention to visit their hospitals and help them control the epidemic there.

The C.D.C. team from Atlanta arrived yesterday as health workers caring for SARS patients in hospitals in the Toronto area were advised to wear two sets of gloves and two gowns as well as full face shields while caring for patients with SARS, or severe acute respiratory syndrome. Earlier, health workers were advised to wear only one set of gloves and gown and a special mask.

Health officials also advised hospitals and clinics to clean rooms where SARS patients are treated more stringently and to restrict access to those rooms.

One reason for strengthening the already strong infection control measures is that SARS is still being spread to health care workers even though they took the proper precautions in caring for SARS patients. Yesterday, Ontario health officials said that new SARS cases had occurred among health workers at two Toronto hospitals Sunnybrook Hospital and Mount Sinai Hospital last week.

A second reason is that health officials now say that the SARS virus can survive for 24 hours. SARS is a newly discovered member of the coronavirus family. Some coronaviruses are known to be able to survive on objects for up to three hours.

But the SARS "virus has the capacity to survive for 24 hours, that's been studied," said Dr. Dick Zoutman, an infectious disease specialist from Kingston, Ontario, and chairman of the scientific advisory committee on SARS in Toronto.

The finding "raises the specter of transmitting SARS on objects like a pen or a health care aid or something that goes in your mouth, for example a thermometer, and so we've had to take that into account," Dr. Zoutman said.

Health officials still believe that SARS is spread primarily in large droplets from coughs and sneezes. But the new studies on the length of time that the SARS virus can survive to contaminate an object renews concern about the role of the environment in spreading the disease.

"We think the environment in and around a patient's room becomes heavily contaminated with coronavirus that can survive on table tops, bed rails and blood pressure cuffs for 24 hours," said Dr. Donald Low, chief of microbiology at Mount Sinai Hospital in Toronto. A C.D.C. official said that initial studies showing the long survival capacity of the virus were now being repeated.

Health care workers who strictly enforce infection control measures in caring for patients may then become contaminated when they leave a patient's room and take off their protective gear, Dr. Low said.

Dr. James Young, the Ontario commissioner of public safety, said that health officials began advising the more stringent infection control measures among health workers after "re-evaluating our isolation techniques and procedures and recommendations to hospitals" over the weekend. Dr. Young said his team issued "a new set of guidelines to protect our workers in every way that we can think of."

Dr. Young said Ontario had invited experts from the national government's agency, Health Canada, and the C.D.C. in Atlanta "to talk with us about these measures and give us their ideas and recommendations."

The new measures will help guide hospitals elsewhere in controlling the disease, Dr. Young said.

"We thought we had it right, we thought we had our workers protected, and it worked for a good deal of time," Dr. Young said.

But Dr. Young went on to acknowledge that health officials had overlooked certain factors that might have contributed to further spread of SARS. "What we didn't count on was the extreme risks" involved "or the fatigue factor that comes into play over time and may expose our workers," Dr. Young said.

One of the transmissions of SARS to a health care worker last week involved a nurse at Mount Sinai Hospital in Toronto. Her case raised public concern after health officials disclosed on Sunday that she twice rode a busy commuter train between Toronto and Burlington on the evening of April 14 and the morning of April 15 to and from work while exhibiting early symptoms of SARS.

Health officials said they were interested only in finding the six passengers who shared seats nearest the nurse three people on each trip.

Officials declined to disclose the nurse's name but did say that the three passengers who shared seats with her on the morning trip discussed SARS while one also read from a communicable disease handbook. Health officials said the chances of the nurse's spreading the disease were considered low because at the time she rode the train, her symptoms were mild and thought not to be infectious.

Canada and the United States have had an epidemiologist working with each other's SARS investigating teams from early in the epidemic to exchange information rapidly. But Dr. Julie L. Gerberding, the director of C.D.C. in Atlanta, in answer to a question at a news conference yesterday, said that her agency could not send additional experts until a request from Toronto officials had been cleared through the Ontario and federal Canadian governments. The reason is that the C.D.C. can respond to requests only from another nation, not a city or province.

C.D.C. and Canadian health officials could not be reached for further comment. The C.D.C. was criticized after the anthrax episodes in the fall of 2001, accused of poor communications to the public and health professionals. The C.D.C. has earned high marks as it has striven to improve communications, though there have been problems. Many reporters could not participate in yesterday's news teleconference because the C.D.C. provided the wrong number.

Health Canada plans to hold a meeting next week to share knowledge about the disease and discuss ideas about how to better contain its spread, Dr. Paul Gully, senior director general of the department's population and public health branch, said in Ottawa. The meeting will be held in Canada, but the time and place have yet to be determined.