ABSTRACT
The rapid emergence of severe acute respiratory syndrome (SARS) in 2003 caught the medical profession by surprise and posed an enormous threat to international health and economies.1-4 By the end of the epidemic in July 2003, 8098 probable cases were reported in 29 countries and regions, with a mortality of 774 (9.6 per cent).5 A novel coronavirus (CoV) was responsible for SARS,6 and the genome sequence of the SARS-CoV was not closely related to any of the previously characterized coronaviruses.7 SARS re-emerged at small scales in late 2003 and early
Severe acute respiratory syndrome (SARS) is a highly infectious conditions with significant morbidity and mortality. Bats are natural reservoirs of SARS-like coronaviruses. The human and civet isolates of SARS-coronavirus nestle phylogenetically within the spectrum of SARS-like coronaviruses. SARS has the potential of being converted from droplet to airborne transmission. The presence of SARS-like coronaviruses in horseshoe bats raises the possible role of bats in previous and potentially future SARS outbreaks in humans. Respiratory failure is the major complication in patients hospitalized with SARS, and about 20 per cent of patients may progress rapidly to acute respiratory distress syndrome (ARDS), requiring intensive care support. Due to the rapid progression of the clinical course of SARS, most of the published data have been uncontrolled or based on retrospective review. Non-invasive positive pressure ventilation (NIPPV) may play a limited supportive role for early ARDS/acute lung injury as a bridge to invasive mechanical ventilation in SARS although it is contraindicated in critically ill patients with multiorgan failure and haemodynamic instability.However, healthcare workers should take adequate respiratory protection in addition to strict contact and droplet precautions when managing patients with SARS as the application of NIPPV may disperse potentially infected aerosols. Further research is needed to examine the exhaled air dispersion distances during application of NIPPV via different masks so that the healthcare providers can better protect themselves within the dangerous distances when managing patients in acute respiratory failure (ARF) due to highly infectious diseases. In addition, more research is needed in the technical improvement of the different NIPPV masks/viral-bacterial filters and the design of safer hospital ward environments in order to prevent nosocomial transmission of these infections. Advances will facilitate management of ARF due to future SARS outbreaks and other emerging infectious diseases such as pandemic influenza.
