21 May Update 61
Taiwan As a result of ongoing assessments WHO recommending, as a measure of precaution, all traveling to Taiwan province, China consider postponing all but essential travel. Advisory based on magnitude of the outbreaks, including number of prevalent cases and daily new cases, local chains of transmission and potential for spread beyond these areas.
Extension of 8 May recommendation of postponing non-essential travel to Taipei. WHO recommends that people consider postponing all but essential travel to Beijing, Hong Kong, Guangdong, Hebei, Inner Mongolia, Shanxi, Taiwan and Tianjin.
Prompt detection and isolation of initial cases in many countries, have prevented further transmission altogether or held additional cases to a very small number. WHO's 27 March recommendation of additional measures aimed at preventing the travel-related spread of SARS include the screening of air departures from areas with recent local transmission of SARS, continues to apply.
Aim of precautionary measures to reduce the impact of SARS and contain the disease while it is still in a relatively early stage.
For more information contact:
Dick Thompson - Communication Officer
Telephone: (+41 22) 791 26 84
20 May Update 60
Philippines (never on restricted travel list) removed from list of areas with recent local transmission. Last locally acquired probable case isolated 30 April - twice maximum incubation period meaning chain of transmission broken.
To date, Philippines DOH has reported a total of 12 probable SARS cases and 2 deaths. All cases have been linked to source cases, five of which imported. One imported case (deceased), from Toronto, infected 7 others in the only chain of secondary transmission - all being family members (1 deceased) or health care workers who treated deceased cases.
The SARS situation in the Philippines illustrates the scale of the emergency effort needed to respond effectively to an imported case and ensure that an outbreak is swiftly contained, reducing number of secondary cases.
The imported case travelled to 5 provinces prior to hospitalization. Contact tracing identified 250 casual and close contacts, 4 of whom developed fever and were quarantined until SARS was excluded.
The list of areas with recent local transmission is issued to facilitate detection/reporting suspect and probable cases through assessment of symptoms of illness in international travellers.
New deaths occurred in China(5), Hong Kong SAR(2), Taiwan(12). Taiwan 39
new probable cases, has the highest number of new cases.
Report on Guangxi (China) visit
Guangxi Province appears to be responding well to its relatively small SARS outbreak. To date, Guangxi has reported 22 probable SARS cases and 3 deaths. Some concern that provences with weak health infrastructure, unable to cope with a SARS. "We found the province well mobilized. There appears to be no major epidemic there," said WHO team leader CK Lee.
Experts found an effective surveillance system set up to detect cases. While no evidence of concealment of cases was found, the numbers of probable SARS cases could be higher due to problems with how cases are being defined. An adequate case reporting system has been set up with daily reports sent to provincial level. No health care workers reported as infected. However, some measures taken may be unwarranted, unsustainable or even inappropriate i.e., three layers of protective gear and up of a 12-layer gauze material in masks.
According to official records, some 260,000 migrant workers returned to Guangxi between April 1 and May 8, of whom 200,000 workers came from neighbouring Guangdong province. Surveillance checkpoints register and screening teams visit villages to monitor returning workers.
WHO requests joint research on origins of the coronavirus to predict its possible reintroduction into the community.
Situation in Taiwan
Taiwan has a cumulative total of 344 probable SARS cases with 40 deaths. On 17 May Taiwan reported 34 new cases, and 36 new cases were reported the following day. Taiwan is most rapidly growing outbreak at present. Possibility that large number of cases represents a backlog of cases only now recognized as SARS. Also lapses in infection control, particularly in emergency rooms.
Local authorities focusing on improving infection control measures. Emergency rooms reorganized to minimize risk of SARS transmission. A new monitoring system with guidelines/procedures for assignment of isolation ward hospital beds.
WHO confident Taiwan will bring outbreak under control. Additional WHO support staff sent to Taiwan soon.
Risk of SARS transmission during air travel
As of 12 May, there have been 35 flights in which that was a probable symptomatic SARS case among passengers or crew, with possible transmission of infection on four flights. The last may have occurred on the 23 March Bangkok to Beijing flight. On 27 March, WHO issued recommendations for pre-flight screening.
control measures, currently recommended by WHO, supported by the available evidence.
Still questions requiring urgent attention include:
WHO asked to review guidelines:
The outcome will serve as
Travel recommendations for Hebei Province (China)
WHO is today recommending that persons planning to travel to Hebei Province, China consider postponing all but essential travel due to:
Similar travel advice is currently in effect for Hong Kong SAR and Taipei and for several areas of mainland China, including Beijing, Guangdong, Inner Mongolia, Shanxi, and Tianjin.
Situation in Singapore
Singapore MOH has determined that cluster of patients and staff in the Institute of Mental Health who developed fever on 11 to 12 May does not represent SARS. None of 34 inpatients and 20 staff have shown any signs of clinical progression characteristic of SARS.
The most recent probable SARS case in Singapore developed symptoms on 27 April and was isolated the following day.
The new deaths occurred in China (7) and Hong Kong SAR (5).
Situation in China
China has today reported 39 new probable SARS cases and 4 new deaths, bringing the cumulative total to 5191 probable cases and 275 deaths.
WHO experts interpret the decrease in case numbers in Beijing as encouraging, but have cautioned against concluding that the city's SARS cases were on a downward trend. They warned that misdiagnosis of cases could have contributed to the lower numbers of probable cases in recent days.
Exclusion as probable cases
WHO officials fear that patients with milder symptoms of SARS are being excluded as probable cases.
There is the assumption that SARS patients must be very sick. If they get better in a few days, not seen as probable cases. Patients also excluded as probable SARS cases simply because they had no known previous SARS case contact. Dr Chin said occurring due to confusion over case definition, not attempt to hide cases.
Patients with milder symptoms start off being isolated as suspect cases. But after their condition improves, they end up being sent to general medical wards, where they could infect other patients. Others may be sent home too early. "They may not need to be hospitalized but they could still be infectious," Dr Chin said.
A study in 75 SARS patients, Lancet by a Hong Kong laboratory - three clinical stages found in patients from the Amoy Gardens cluster
Guidance for mass gatherings
Recommendations in line with WHO efforts to prevent the further international spread of SARS while also protecting the travelling public from unjustified restrictions.
The purpose of the recommendations is to help hosting governments and organizers of such events make decisions that protect domestic populations.
Such decisions are left to the authority of individual countries based on their own assessment and on preparedness and capacity to manage situation
See Guidance for Mass Gatherings: hosting persons arriving from an area with recent local transmission of SARS
Viabilitity of SARS virus
Studies by laboratories in the WHO network indicate that SARS virus in sterilized stool can survive:
The new deaths occurred in China (4), Hong Kong SAR (4), and Taiwan, China (5).
15 May Situation in China
The joint Ministry of Health-WHO team in Guangxi will soon complete its mission. Based on visits and a review of data, the team is of the view that large scale unreported transmission is not occurring in the province.
New guidelines on blood safety WHO has today issued a series of recommendations as precautionary principles to address the theoretical risk that SARS might be transmitted through the transfusion of labile blood products. WHO is stressing that the recommended measures are precautionary.
Guidance for mass gatherings WHO has today issued a series of recommendations for the organizers of mass gatherings hosting persons arriving from an area with recent local transmission of SARS.
According to current understanding of SARS, only persons with symptoms are contagious and can transmit the disease. Close contact is required for transmission.
Wearing of masks by well persons who are travelling from an area with recent local transmission of SARS is not recommended by WHO.
The new deaths occurred in China (4) and Hong Kong SAR (7).
Taiwan, China reported 26 new cases and no new deaths today, bringing the cumulative
total to 264 probable cases and 30 deaths. Taiwan now ranks just below mainland China
in the number of new cases reported since yesterday. Hong Kong SAR reported 5 new
probable cases and Singapore reported no new probable cases today.
14 May Change in status of Toronto WHO has today removed Toronto, Canada from the list of areas with recent local transmission. Toronto has also been removed from the list of areas for which WHO has issued recommendations pertaining to international travel.
The most important WHO consideration is whether 20 days have passed since the last locally acquired case was isolated or died. The last locally acquired case in Canada was isolated on 20 April.
Situation in China
Members of a WHO team currently in Hebei report that SARS has already spread to 9 of the province's 11 prefectures. Forty of Hebei's SARS cases have been traced to migrant workers returning home.
Hebei has adopted a unique approach to SARS that relies on support from local communities. Physicians are working in individual townships to record all people travelling to and from areas in China with local transmission. Individuals who are found to have fevers are sent to fever clinics for further monitoring. Workers from provinces with recent local transmission are placed in observation for as long as 3 weeks, during which their temperatures are checked numerous times each day. In some cases, entire villages where cases of SARS in farmers have been detected have been placed under quarantine.
The WHO team has found that infection control measures in Hebei hospitals are scrupulously following the national guidelines, which may help explain low rate of infection in health care workers. Up to now, fewer than 10% of the province's front-line health care staff have become infected, a figure considered by team members to be remarkably low.
Situation in Singapore Health officials reported yesterday a cluster of 24 patients and 6 nurses from the Institute of Mental Health who have recently developed fevers. All but one of the patients were from a single ward at the Institute.
In line with aggressive containment efforts in Singapore, officials decided to treat cases as though they represented a cluster of SARS cases until proven otherwise.
Singaporean authorities are carrying out active contact tracing. All patients discharged from the Institute of Mental Health from 23 April until 2 May are being recalled for medical consultations at Tan Tock Seng Hospital. Any patients discharged after 3 May will be quarantined at home for 10 days beginning 13 May. Close contacts of the staff and patients affected in the cluster are also being quarantined at home.
The WHO team in Singapore reported today some signs that patients in the cluster, many of whom are elderly, may be ill from causes other than SARS.
The new deaths occurred in Canada (1), China (5), Hong Kong SAR (2),
and Taiwan, China (6).
13 May To date, the WHO approach to SARS has been aimed at sealing off opportunities for further spread, both within countries reporting cases and internationally.
In the absence of a vaccine, the most effective way to control a new disease such as SAS is to break the chain of transmission from infected to healthy persons.
For SARS, three activities – case detection, patient isolation, and contact tracing – can reduce the number of people exposed to each infectious case and eventually break the chain of transmission.
Case detection aims to identify SARS cases as soon after onset of illness as possible. Once cases are identified, the next step is to ensure their prompt isolation, in a properly equipped facility, and management according to strict procedures of infection control. The third activity – the detective work – involves the identification of all close contacts of each case and assurance of their careful follow-up, including daily health checks and possible voluntary home isolation.
Together, these activities limit the daily number of contacts possible for each potentially infectious case. They also work to shorten the amount of time that lapses between onset of illness and isolation of the patient, thus reducing opportunities for the virus to spread to others.
If each new SARS patient infects more than one additional person, then the number of new cases will increase with time. If each new SARS patient infects one further person, then the number of new cases will remain static. However, if each new SARS patient infects, on average, less than one further person, then the number of new cases will fall and the outbreak will die out. This remains WHO's overall objective, both in its support to individual countries and globally.
The example of Singapore Nonetheless, as SARS has clearly demonstrated, a single case admitted to an unprepared hospital can ignite a new outbreak.
While trends are moving in an encouraging direction in many areas, even greater focus on control measures is needed if SARS is to be contained globally. WHO experiences with outbreaks of Ebola haemorrhagic fever have repeatedly shown that the initial stages of containment are the most dangerous time to start lowering the level of control.
"We can't become complacent," says Michael J. Ryan, Coordinator of WHO's Global Alert and Response Programme. "In fact, this is the time to intensify our efforts."
The new deaths occurred in China (10), Hong Kong SAR (7), and Taiwan, China (4). China has reported today 80 new probable cases and 10 deaths New cases were concentrated in Beijing (48), Hebei (14), and Shanxi (13).
Taiwan reported 23 new cases and 4 deaths
"Singapore has greatly increased its containment measures aimed at halting further transmission of SARS. A special effort has been made to raise the standards of infection control at Tan Tock Seng Hospital, which was converted into the country's specialized hospital for managing SARS patients." "Singapore has also introduced strict screening measures for all outbound air passengers..."
"Last week, of the 70,000 passengers that were screened, 58 were found to have fever and taken to the SARS-designated hospital. Two were later admitted as suspect SARS cases, but neither has been reclassified as probable. All contacts of known SARS cases are being placed under supervised home quarantine for 10 days."
"Situation in Hong Kong today reported 5 new probable cases of SARS. The territory has seen a steady decline in the number of new cases, which has been in the single digits for the past eight days." "All close contacts of known SARS cases are quarantined at home. In addition, their Hong Kong Identity Card numbers are passed to the Immigration Department to ensure that these individuals cannot leave the territory. Contact tracing has established epidemiological links for the majority of Hong Kong's SARS patients. Around 8.6% of patients have no identifiable exposure source. Detailed investigation is ongoing. The last known exportation of a SARS case from Hong Kong occurred on 18 April."
"Beginning today, WHO is posting on its website a new table indicating those areas with recent local transmission for which WHO has issued recommendations pertaining to international travel. Two recommended measures are specified: exit screening for international travellers departing the area, and traveller to consider postponing all but essential travel to the area. The table will be updated daily.
No travel restrictions are recommended by WHO to any other areas."
Situation in China "Although today's figures are lower, WHO officials in Beijing have cautioned against any clear conclusions that the SARS outbreak has begun to decline in the city"
"WHO officials will be working with Beijing authorities to improve data analysis and develop policy options for responding to the outbreak. The lack of known contact to a SARS patient among the more recently reported cases could be related to either how cases are being reported or how and where the virus is being transmitted."
"Philippines - that the cluster of SARS cases has been well contained. There appears to be no increased transmission risk in the Philippines. For these reasons, WHO does not recommend any restrictions on travel to the Philippines."
Mongolia -Yesterday Mongolia was removed from the list of countries with recent local transmission. Twenty days had passed since the only case resulting from local transmission was appropriately isolated"
"WHO Director-General nominee, Dr. Jong-Wook Lee, arrived in Beijing today for a one-day visit" "Yesterday, a WHO team travelled to Hebei Province, which borders Beijing municipality, to assess the SARS situation. The WHO investigation is being conducted in collaboration with the Ministry of Health and marks the first time that a joint WHO-Ministry of Health team has been sent to a province." "The cumulative total of probable SARS cases in Mongolia is nine. No deaths have occurred. Six of the nine cases have recovered. The additional three cases remain in isolation in a SARS-designated hospital."
"As of today, a cumulative total of 7183 probable cases of SARS and 514 deaths have been reported from 30 countries on six continents. This represents an increase of 144 new cases and 8 deaths when compared with yesterday. Of the new deaths, 6 were reported in China, and 2 were reported in Hong Kong SAR."
8 May "...WHO is now recommending, as a measure of precaution, that people planning to travel to Tianjin and Inner Mongolia provinces of China, and Taipei in Taiwan province of China consider postponing all but essential travel."
"...In many countries, prompt detection and isolation of initial cases have prevented further transmission altogether or held additional cases to a very small number. On 27 March, WHO recommended additional measures aimed at preventing the travel-related spread of SARS. These recommended measures, which include the screening of air passengers departing from areas with recent local transmission of SARS, continue to apply."
Case fatality ratio
WHO has revised estimates of case fatality ratio of SARS, as the proportion of all people with a disease who will die from the disease, based on data from 5 countries finding that the ratio ranges from 0% to 50% depending on the age group affected with an overall estimate of case fatality of 14% to 15%. Estimates range from 5% to 19% in different countries. Gives analysis and background for estimation.
"...the case fatality ratio is estimated to be less than 1% in persons aged 24 years or younger, 6% in persons
aged 25 to 44 years, 15% in persons aged 45 to 64 years, and greater than 50% in
persons aged 65 years and older."
Maximum incubation period
"...WHO continues to conclude that the current best estimate of the maximum incubation period is 10 days..." and discusses "...how the incubation period as been determined and its purpose having "analysed the incubation periods of individuals with well-defined single-point exposures in three areas of the world".
Early isolation of all suspect and probable cases of SARS continues to be recommended
Particularly impressive among the measures, which is some cases exceed those recommended by WHO, are exit screening procedures at border checkpoints, publication of information on all buildings where residents have developed SARS, procedures for isolation and quarantine, and aggressive contract tracing that relies on a system initially developed by the police force for use in criminal investigations."
"The number of new cases (in the single digits for the last several days) has steadily declined, suggesting that the outbreak has peaked."
Hong Kong has introduced: border point medical posts supported by infrared temperature scanners, all travellers required to sign health declarations, prohibit close contacts of SARS patients from leaving Hong Kong, monitoring residents via their Hong Kong Identity Card numbers, strategic computer system to facilitate contact tracing, geographic clusters of SARS cases, or so-called "hot spots" in certain buildings identified, data on cases and their contacts maintained in centralized, dedicated eSARS database, public information and education campaigns to increase SARS awareness and encouraging people experiencing symptoms to seek prompt medical care
"Cases continued to rise in the two most heavily affected provinces outside of the capital, Shanxi and Inner Mongolia, with 11 and 21 probable cases reported, for a total of 369 and 251 respectively.
WHO experts will visit Hebei province in China as part of a joint Ministry of Health-WHO team to assess the SARS situation and the capacity to cope with an outbreak.
Four WHO experts will leave on 8 May with experts from China's Ministry of Health for the province, which surrounds Beijing and is home to some of the capital's "floating population" of migrant workers."
Clinicians are advised that patients should not have their case definition category downgraded while awaiting results of laboratory testing or on the bases of negative results.
"The number of new SARS cases continues to increase steadily in China, particularly in Beijing. Today, China reported 187 new cases and 11 deaths, more than half of which were in the capital"
"WHO has today updated its case definition for SARS to take into account the appropriate use of results from laboratory tests. Several diagnostic tests have been developed by various laboratories for the detection of the SARS virus and antibodies to the virus. However, all presently available tests have specific strengths and weaknesses.
For this reason, WHO continues to advise clinicians that patients should not have their case definition category downgraded while awaiting results of laboratory testing or on the basis of negative results."
"WHO, supported by members of its laboratory network for SARS diagnosis and the Robert-Koch Institute, Germany, is making standardized reagents available to improve reliability and support the quality assurance of diagnostic tests for SARS. "
"Shanghai is to enforce stricter SARS preventive measures"
"...travel advisory for Toronto lifted..." "Travel advisories for Beijing, Hong Kong SAR, and Guangdong and Shanxi provinces, China, remain in effect." "...The magnitude of probable SARS cases has decreased. Twenty days have passed since the last cases of community transmission occurred. No new confirmed exportation of cases has occurred."
"China's largest number of cumulative cases remains concentrated in Guangdong Province, where the SARS outbreak began in mid-November. Only 10% of these cases are current. As 1201 patients have been discharged and 51 have died, there are less than 150 SARS cases remaining in Guangdong's health care system."
Beijing reported the highest number of new cases (101) and deaths (9), for a cumulative total of 1440 probable cases and 75 deaths. Of these new cases, 31 were previously reported as suspect cases while 70 were reported for the first time"
"...The disease continued to make its mark elsewhere in the country. Jiangsu Province, which borders Shanghai, reported its first case today. More cases were reported in western China, with 34 more probable cases from Shanxi and seven more from Inner Mongolia, giving a total of 299 and 127 probable cases respectively. One fifth of the cases (65) in Shanxi Province are among health workers.
Hebei... with nine more probable cases, giving a total of 48. Tianjin reported five more probable cases for a total of 49 cases, while Guangdong reported six, for a total of 1405.
WHO has today removed Viet Nam from the list of affected areas, making it the first country to successfully contain its SARS outbreak. The change in Viet Nam's status follows 20 consecutive days (the duration of t wo incubation periods) since the last new case was detected.
WHO plans to hold an international scientific meeting in Geneva 17-18 June 2003 "to review the epidemiological, clinical management and laboratory findings on SARS and to discuss global control strategies." To be invited: Key participants in current outbreak, public health authorities.
WHO biosafety guidelines for handling of SARS specimens.
Major Points from WHO Teleconference Briefing 23 April
"...Today, we are making a further recommendation in that we are going to recommend that people who have unnecessary travel to Shangxi, to Beijing, and to Toronto postpone that travel if possible because, as was the case for Hong Kong and Guangdong, we now have these areas which have a high magnitude of disease, a great risk of transmission locally outside of the usual health workers, but still traceable in most instances, and also there is exporting of cases."
Discussion of China's disclosure of additional figures not previously reported - "The Chinese government today announced a further 109 SARS cases in Beijing. This latest report comes after Sunday's announcement of 339 previously undisclosed SARS patients. There is no breakdown of the number of patients in regular and military hospitals. The new numbers bring the total of confirmed cases in China to 1,959.