Severe acute respiratory syndrome: time to circle the wagons.

I t is rare, as physicians, to witness a disease from its index case to its global impact within a short time. The severe acute respiratory syndrome (SARS) epidemic started innocently enough as a mysterious illness in November 2002 in the southeast Chinese province of Guangdong. By the following February, five people were reported to have died and more than 300 were infected. Since this innocuous start, there have now been approximately 5,000 cases in 26 countries, with numbers increasing daily. This disease is having tremendous impact on the world economy in that it has rocked Asian markets, ruined tourist trade, and is said to be costing the Canadian economy approximately 30 million dollars per day. Schools in several countries have been closed, thousands have been quarantined, and there are rumors of martial law being imposed in Beijing, China. SARS has even restricted medical education in Toronto (1). In adults, SARS presents as a multiple system disease, with fever, nonproductive cough, and dyspnea as the most prominent clinical manifestations. Chest infiltrates are the most common radiologic finding. Death is usually due to severe atypical pneumonia and respiratory failure, while morbidity is associated with nonspecific generalized inflammation of many organ systems (2–5). The worldwide impact of this disease reveals the double-edged sword of the global village that we now inhabit. On the one hand, we are able to share information almost instantaneously, and from afar, scientists can contribute to the understanding and treatment of epidemics such as SARS. Easy, affordable, and convenient travel, on the other hand, makes our effort to limit its spread very difficult. For instance, closer to the United States, the disease has led to approximately 140 Ontario residents being infected and 20 dying. This started with an index case of a 78-yr-old woman who traveled to Hong Kong in February 2003. The rapid spread to 26 countries indicates that no population seems to be immune. Containment measures are unlikely to succeed until we determine the exact means of spread of the infecting agent (6). Moreover, children are especially vulnerable because they are in close contact with adults (parents and relatives) and isolation from family members is likely to be a traumatic experience. The report by Dr. Chiu and colleagues (7) is an important contribution because it is the first report of the clinical course and outcome of SARS in children. It is, therefore, pertinent to all who practice pediatric critical care medicine. Dr. Chiu and colleagues report SARS in 21 children from a housing estate in Hong Kong. These children came from 17 families, in whom 13 families had other members affected with SARS. The importance of this report is several-fold. It gives us a first glimpse of the clinical findings and outcome in children affected with SARS, and it compares symptomatology and outcomes with adults. Just as important, it outlines a protocol for treatment of children. Although not a randomized clinical trial, the importance of the disease and the timely nature of this report cannot be overemphasized. It is likely to lead to diagnostic and treatment options because many of the advances in medicine have come from detailed observation and innovative ideas arising from the immersion of the investigators into poorly understood clinical realities (8). Dr. Chiu and his team should, therefore, be commended for providing us with this timely information, especially because very little is known about the effect of SARS in children. In fact, little is known about SARS even in adults. It is obvious that we have more questions than answers about this mysterious disease. Although it is likely that this disease is caused by a coronavirus long known to veterinary medicine because it routinely affects livestock, ducks, and other domestic animals (9), the intimate details of this particular coronavirus is still being unraveled. Moreover, identification has not lead to a decrease in spread (10). It is possible that multiple strains or rapid mutation of the virus may underlie these unexpected findings. Another open question is precisely how the disease spreads. Some victims in close contact may not be affected with the virus, whereas others may. This observation has led to speculation that aerosol droplets by coughing and sneezing, direct contact, and spread by contaminated fecal matter may all play a role. An important message from this report is that children are likely to be asymptomatic or suffer from milder disease and less morbidity and mortality compared with adults. Nonspecific symptoms including fever, malaise, and loss of appetite are the most prominent symptoms. Dyspnea, tachypnea, and findings such as lung crepitations are uncommon. Despite radiographic changes in all children during their illness, 20 of 21 children had a normal chest examination compared with most adults who had inspiratory crackles at lung bases (2). This difference in clinical manifestation of the disease is intriguing. Whether this is due to infection with a separate strain of the virus in children is unlikely. What is more plausible is that the body’s response in children may be different from adults such that lung damage is less. This is supported by Dr. Fauci’s (11) contention that “the immunologic and inflammatory response of the body could be contributing significantly to the damage in the lungs. ” Another possible explanation for better outcomes in children is the fact that they were previously healthy, whereas adults who died from SARS had significant co-morbidities (2). Whatever the reason, the outcome in children is heartening and deserves further study. Two additional points merit discussion. First, although SARS produced a relatively mild clinical picture in these healthy children, one cannot downplay its potential consequences if an outbreak *See also p. 279.