This site is intended for health professionals only

SARS: unmasking an emerging threat

Liz Rosies
RGN MSc(TravelMed)
Travel Health Advisor
Author of

SARS (severe acute respiratory syndrome) is a "flu-like" illness that first appeared in the Guangdong area of China in November 2002. The virus was carried to Hong Kong in early March and initially spread to Vietnam, Singapore and Toronto. Within a very short period of time it had spread across the globe by means of international air routes to more than 30 countries.(3) The World Health Organization (WHO) declared the disease "a worldwide threat", bringing chaos to health structures, as well as affecting the very social and economic nature of countries around the globe.(4) At a World Health briefing in May, health officials recognised SARS as "the first severe infectious disease to emerge in the 21st century" and warned that it was a threat to any country with an international airport.(5)
Since the first outbreak of SARS much about the disease still remains a mystery; however, many discoveries have been made as experts try to put the pieces into place. Early research indicates that the disease is caused by the coronavirus, a virus usually responsible for the common cold. This variation of the virus has never before been seen in human populations.(6) The experiences of SARS in both Hong Kong and Toronto have been well documented and help to provide ongoing information about the disease. Research indicates that, following an incubation period of 2-10 days, 99% of SARS patients experience a sudden onset of fever, 71% of cases display influenza-like symptoms, and 51% have a dry cough. Diarrhoea has been recorded in a quarter of all cases.(7) Initial research also indicates one common feature - all infected persons have either been to an infected area or have been in direct contact with a known case of SARS within 10 days of the onset of symptoms.
Following infection, the SARS patient develops an atypical pneumonia that can lead to death in approximately 15% of cases. Canadian reports also indicate that death rates are higher in those with existing medical problems, while in Hong Kong the death rate is 55% in those infected patients over the age of 65.(8)

Transmission of SARS
SARS can be transmitted through various routes. One mode of transmission is through respiratory droplets when an infected person coughs or sneezes. This fact has enabled health professionals to ensure strict levels of infection control when treating SARS patients in hospitals around the world to prevent local spread. There appears to be no evidence of airborne transmission due to the fact that spread has not been noticed on airlines leaving infected areas.
The SARS virus is able to survive for one to two days at room temperature and on frequently touched surfaces. Normal washing and cleaning of surfaces using disinfectants has proved effective at preventing spread. The virus can survive for up to four days in human faeces.(9) However, due to the fact that SARS is a new disease, it is possible that further modes of transmission exist that have not yet been discovered.
Advising travellers
WHO is updating travellers about SARS-infected areas on a daily basis via its website.(10) Using information gathered from infected countries, warnings and advice can be given. The advice is reviewed on a daily basis, and before any travel advisory being lifted cases of the disease have to fall below five on a given day, with no new cases recorded outside of the immediate contacts of an infected person. On 28 April 2003 Vietnam was declared the first country to be free of SARS. This was achieved through a massive infection control programme and joint effort with WHO, and provides hope that control of the disease is feasible through education and strict quarantine.(11)
When advising those who need to undertake essential travel to SARS-infected areas, it is vital that they are made aware of the signs and symptoms of SARS before travel.(12) As neither medication nor vaccine exists to control the disease, it is important that control of spread is ­established through traveller awareness. If travellers are forced to travel in close contact (within one metre) with a person having suspected symptoms, a facemask or handkerchief over the mouth and nose should be used to avoid infection.
Travellers should maintain good communication with those back at home using email and telephone, and keep updated on travel advisories from an up-to-date source, as information and advice are constantly changing.
Those going to highly infected areas should ensure that they have adequate insurance cover before travel. If at any time they feel ill they should seek medical attention immediately. If medical attention is sought while away or on return, they should ensure that they alert medical staff that they have travelled to a SARS-infected area within the last 10 days.
When travelling it is important that frequent handwashing and personal hygiene are adhered to. Travellers should be advised to avoid crowded places such as sports events and conferences, and should also avoid travelling on crowded public transport in highly infected areas. It should also be remembered that anyone who is suffering from a respiratory problem and trying to take a flight in an infected country could be refused access to the flight. Such patients will need a letter from their doctor.
Practice implications
During these first few months it has been difficult to establish concrete guidelines regarding SARS due to the changing nature of information. As speculation is replaced by research, we are gradually building a picture of this new disease. It is therefore essential that as nurses we base our advice on the best, most scientific evidence available. By using the internet we are able to receive updates and advisories from around the world. This information will not only increase our knowledge, but also reassure our travellers - by unmasking what is for many a threat to livelihood, health structures and economies.
Please note that the information contained in this article was correct at the time of going to press. For more up-to-date information please refer to the Resources section.


  1. WHO. Press release. 15 March 2003. Available from URL: http://www.who. int/csr/don/2003_03_16/en
  2. WHO. Cumulative Number of ­probable recorded cases of SARS. Available from URL:
  3. Pro-Med Updates. Available from URL:
  4. SARS: epidemics and economics. Business Week 28 April 2003. Available from URL: http://www.businessweek (registration required).
  5. WHO. Severe acute respiratory syndrome (SARS) - status of the outbreak and lessons for the immediate future. 20 May 2003. Available from URL: sars_wha.pdf
  6. Bonn D. Closing in on the cause of SARS. Lancet Inf Dis 2003;3(5):268.
  7. Booth CM, Matukas LM, Tomlinson GA, et al. Clinical features and short-term outcomes of 144 patients with SARS in the Greater Toronto area. JAMA 2003; Published online 6 May 2003. Available from URL:
  8. Donnelly CA, Ghani AC, Leung GM, et al. Epidemiological ­determinants of spread of causal agent of severe acute respiratory syndrome in Hong Kong. Lancet 2003;361:1761.
  9. CDC SARS Information. Available from URL: ncidod/sars
  10. WHO Travel Advisory Website. Available from URL: http://www.who. int/entity/csr/sarsarchive/en
  11. BBC News. Vietnam beats SARS. 28 April 2003. Available from URL:
  12. PHLS. Frequently asked questions about SARS. Available from URL:

ProMed Updates on the global situation

Updates and travel advisories

Centers for Disease Control (CDC)
Updates for professionals

Public Health Laboratory Service
UK advice and updates

For guidance for primary care ­practitioners on investigation, management and reporting of SARS cases and contacts (including ­community ­infection control)refer to the ­following PHLS webpages

SARS Resource