Analyzing what it said was more complete data, the World Health Organization (WHO) said Wednesday that the estimated overall death rate from SARS was about 15 percent -- double its previous estimate.
The new rate is still lower than the nearly 20 percent reported Tuesday by researchers who studied the course of the epidemic of severe acute respiratory syndrome in Hong Kong. Those scientists used different statistical techniques.
Even so, the revised death rate indicates that as new information from the evolving epidemic comes in, SARS is proving much more serious than first thought. Early estimates of the death rate had ranged down to about 2 percent.
The health agency said its new figures were based on the latest detailed data from Canada, China, Hong Kong, Singapore and Vietnam. The death rates varied by age: more than 50 percent in people 65 and older; 15 percent in those 45 to 64; 6 percent among those 25 to 44; and 1 percent for those 24 and younger.
The new mortality rates, like the old ones, are tentative because the epidemic is thought likely to change as more information comes in.
The WHO did not report the higher figures earlier partly because it did not receive the needed data until recent days, said Dr. Michael Ryan, a medical officer at the agency. He added that the WHO also did not want to "panic the world" by releasing death rates that could turn out to be significant overestimates.
Calculating death rates for new diseases like SARS is notoriously difficult for epidemiologists, particularly if there is no definitive diagnostic test, as is the case with SARS. The final death rate will not be known until the epidemic has run its course. Moreover, death rates can vary from one set of patients to another, depending on factors like the amount of virus transmitted, where it entered the body, and the functioning of an individual's immune system.
Another statistic that has been hard to calculate for SARS is the incubation period -- the interval from the time of exposure to the onset of symptoms -- because individuals may have been exposed to the virus on a number of occasions.
On Tuesday, the same study that found a higher death rate in Hong Kong suggested that the incubation period for SARS might be as long as 14 days. But that analysis, published in the medical journal Lancet, was based on only 57 cases among a much larger group.
On Wednesday, the WHO stood by its 10-day estimate. That figure was determined by reviewing cases in which the patient had a single documented exposure to a known SARS patient in Canada, Europe or Singapore, the agency said.
The incubation period has major implications for control of the epidemic.
A 14-day period could mean longer isolation periods for patients and longer quarantines for people who have had contact with them. It could require health workers to trace four more days' worth of patient contacts. And it could lengthen by eight days, to 28, the period health officials use to declare an area free of SARS.
Ryan said the Lancet study held important additional information that needs to be analyzed further.
A sea warning for Typhoon Champi could be issued as early as Wednesday night, possibly followed by a land warning on Thursday night or Friday, as the storm approaches Taiwan, the Central Weather Administration (CWA) said yesterday. The typhoon is expected to have its greatest impact on Taiwan on Friday and Saturday, bringing heavy rain to central and northern Taiwan and to Yilan and Hualien counties in the east, CWA forecaster Liu Pei-teng (劉沛滕) said. As of 2pm yesterday, Champi was about 2,470km east-southeast of Oluanpi (鵝鑾鼻), Taiwan’s southernmost tip, moving westnorthwest at 20kph. It had maximum sustained winds of 191kph and a
EAST OF GUAM: Tropical Storm Champi is forecast to strengthen into a typhoon, but its effect on Taiwan is uncertain due to the presence of a high-pressure system Tropical Storm Champi formed yesterday and has the potential to increase in strength, the Central Weather Administration (CWA) said yesterday. Forecasters are closely monitoring a Pacific high-pressure system that would dictate whether the storm turns north or moves toward Taiwan next week, the CWA said. The most likely scenario is that it turns northward after passing the Ryukyu Islands, CWA forecaster Cheng Chieh-jen (鄭傑仁) said. As of 8pm yesterday, Champi was east of Guam moving west-northwest at 20kph, CWA data showed. It had maximum sustained winds near the center of 72kph and gusts of up to 101kph, the data showed. If the Pacific high-pressure system
ORIGINS: A Taiwanese doctor practicing in Japan said he no longer needed to cover the nationality label on his license with a sticker, as it used to confuse his patients Starting this month, Taiwanese professionals working in Japan can list “Taiwan” as their place of origin following Tokyo’s easing of rules on “nationality” in official licensing documents. The change was announced yesterday by the Japan-Taiwan Friendship Parliamentarians’ League in Tokyo. The license revision covers 322 professions, including doctors and nurses. Previously, Taiwanese had to list “China” as their nationality on professional certifications and licenses, but the new rules updated the “nationality” to “nationality and region” or “nationality, etc,” allowing Taiwanese to use the name “Taiwan.” The league held a meeting about the revision at the House of Representatives Members’ Office Building in Tokyo
US-made M1A2T Abrams tanks are to participate in a major military exercise for the second time, when the Lien Yung exercise (聯勇操演) begin next month, a military source said yesterday. The army’s 584th Armored Brigade, which operates the US-built tanks, has already transported them to the Joint Operations Training Base in Pingtung County for the drills from late next month to December, the source said. During the month-long joint military exercise in southern Taiwan, the tanks’ crew would test their combat coordination, said the source, who asked not to be named. The M1A2T Abrams tanks were included in a major Taiwanese military exercise