SARS: DOWN BUT STILL A THREAT (original) (raw)

DISCUSSION

The Global Health Challenge

The emergence of SARS illustrates the challenge of battling infectious diseases in an increasingly globalized world. SARS is the latest of more than 35 new or reemerged infectious diseases over the last 30 years. Infectious diseases have long raged through human communities, but forces of globalization—including rapid growth in international trade and travel and increasing urbanization—have amplified their spread and impact. These same forces of globalization, however, also have led to significant advances in communication, travel, and technology, which have aided in the fight against infectious diseases.

Downsides of Globalization

Population growth and development are bringing more people into contact with non-domesticated animals, introducing new diseases more frequently into the human population. The transmission of pathogens from animals to humans is a process called zoonosis. Some researchers believe that SARS may have originated in China in animals such as wildcat species that were trapped and sold as food in exotic markets. In mid-August 2003, China lifted the ban on the sale and consumption of exotic animals imposed during the SARS epidemic.

Modern travel and labor migration patterns played a key role in spreading SARS after it emerged in November 2002 in Guangdong Province, China (see Figure 5-7). From Guangdong, the disease made its way to Hong Kong and then to Vietnam, Singapore, and Taiwan as well as Europe and North America.

FIGURE 5-7. Portrait of a superspreader: spread of SARS from the Metropole Hotel in Hong Kong as of March 28, 2003.

FIGURE 5-7

Portrait of a superspreader: spread of SARS from the Metropole Hotel in Hong Kong as of March 28, 2003.

In addition to spreading the disease geographically, global links also have amplified the economic and political impact of the disease. Even though SARS has killed far fewer people up to now—around 815—than those who die each year from more common maladies such as pneumonia, influenza, malaria, and tuberculosis, as a new disease it was more disruptive and generated more attention (see Figure 5-8). The disease exhibited some characteristics of a potentially explosive epidemic in the early stages, and SARS hit countries that have extensive commercial links with other parts of the world, generating widespread economic disruptions and media attention.

FIGURE 5-8. Comparative worldwide mortality of infectious diseases.a.

FIGURE 5-8

Comparative worldwide mortality of infectious diseases.a. aWHO estimates of worldwide deaths in 2001 from major infectious diseases. SARS deaths occurred from November 2002 to July 2003.

Benefits of Globalization

Intense international media coverage facilitated by global communication networks increased pressure on governments to respond effectively to SARS and prompted many citizens and healthcare workers to be vigilant in taking precautions, monitoring symptoms, and seeking early treatment.

Modern communications and medical technologies provided key tools to combat SARS.

Economic and Political Fallout of SARS

Government and private sector economists have had difficulty calculating the costs of the SARS epidemic. Early on, forecasters estimated that the macroeconomic impact would be negligible but hastily cut growth estimates for several economies, including China, as the disease spread, cases mounted, and the situation appeared to be out of control (see Table 5-3). Service industries, particularly airlines and tourism, were affected immediately. SARS began to threaten the retail and manufacturing sectors, particularly in China, when business trips and trade fairs were canceled, new orders were placed on hold, and investors delayed new expansion and constructions plans.

TABLE 5-3. Economic Impact of SARS.

TABLE 5-3

Economic Impact of SARS. NOTE: The chart below reflects estimates for 2003 based on second quarter data, but the delayed impact and potential for recurrence in the fall suggest that it may be premature to measure the full impact on growth.

Recent data suggest that growth in most countries plummeted in April and May but started to recover as the disease was brought under control, reports of new cases dwindled, and the WHO removed countries from its travel advisory list. Most notably, no major disruptions in trade and investment flows occurred. Moreover, most factories in China, including those in Guangdong where the disease originated, continued to operate even during the height of the epidemic. In some countries, monetary and fiscal stimulus packages also helped to cushion the blow.

Certain locales, notably Hong Kong, Beijing, and Toronto, were hurt more than others. Moreover, additional indirect costs—the so-called SARS tax—probably will be incurred by businesses consumers, governments, and nongovernment agencies.

SARS dealt a body blow to the travel and tourism industries, already facing a slowdown from post-9/11 terrorism concerns. They will be slow to recover. Business travel has resumed more rapidly as firms catch up on a backlog of deals, but tourist travel is far below last year’s levels. Hotels in Asia are cutting room rates in a bid to attract customers.

An industry trade group estimates the tourist sector in China, Hong Kong, Singapore, and Vietnam will lose up to $US 10 billion and 3 million jobs this year because of SARS.

Airlines have restored most canceled flights, but carriers will have difficulty recouping lost revenues, and some may be forced into bankruptcy. The airline industry’s slow recovery will be a further drag on the aviation industry. Asian airlines were to account for one-quarter of Airbus deliveries and 30 percent of Boeing’s deliveries in 2003. Several Asia-Pacific carriers asked Airbus and Boeing to postpone deliveries of new aircraft. Both manufacturers have been counting on robust growth in the Asian travel market to boost revenues.

Anecdotal evidence suggests that some export-oriented industries, particularly clothing manufacturers, temporarily shifted some orders to Bangladesh, Turkey, India, and Pakistan. Foreign electronics manufacturers, including a large Japanese electronics firm, shifted some production to plants in Philippines and Malaysia with highly specialized sectors and relatively low costs. There is no evidence to suggest that foreign manufacturers pulled out investments or permanently shifted production outside China or East Asian production plants. Some multinationals probably have begun to rethink the costs and benefits of concentrating investment in one country or region, however.

SARS has had minimal impact on global semiconductor production, even though nearly 80 percent of production in this $US 8 billion industry is located in Asia, largely in Taiwan and China.

None of the semiconductor operations was forced to curtail production, although SARS disrupted some visits by foreign equipment suppliers and prompted the temporary closing of some Hong Kong sales and marketing offices.

Political Impact

SARS seriously tested the leadership skills of politicians and civil servants in every country affected. The public was quick to criticize leaders in China, Canada, Hong Kong, and Taiwan for failing to grasp the seriousness of the situation, to act quickly to contain the spread, and to accept responsibility for missteps. In some countries, public confidence in the ability of government leaders and state institutions to protect them may be permanently damaged.

In contrast, the WHO and CDC lauded the Vietnamese government’s swift action and willingness to accept outside assistance, noting these factors were key to its success in containing the spread of SARS. In Singapore, the public expressed confidence and support for the government’s rigorous efforts to identify and isolate suspected SARS patients. An early April poll showed three out of four Singaporeans were confident that the government could stop SARS.

Tracking the Downturn in SARS

Since WHO first issued a global alert about SARS in March 2003, almost 8,500 probable cases have been reported from 29 countries around the world, with most cases (over 7,000) occurring in China. At one point in May, over 180 new infections were being reported daily, mostly in China.

The number of SARS cases peaked in May and steadily declined worldwide with the WHO declaring on July 5 that all transmission chains of the disease had been broken. The decline may reflect a seasonal retreat of the disease in warmer months, which is common for respiratory illnesses in temperate climates. Nonetheless, the downturn clearly illustrates that, even in a globalized world, the old-fashioned work of identifying and isolating suspected cases, tracing and quarantining others who might be exposed, and issuing travel advisories can control an emerging disease.

Surveillance

The first line of defense in arresting the spread of SARS has been the success in identifying possible cases—despite the lack of a proven screening test and symptoms common to many respiratory ailments. Taking people’s temperature generally has been the simplest, most cost-effective means of initial screening for possible SARS cases, followed by clinical examination for respiratory symptoms in those with fevers.11

BOX 5-3SARS Basics

Origins. The SARS epidemic spread rapidly because people had little immunity to the newly emerged coronavirus that causes the disease. Close contact with sick individuals appears to be the primary means of virus transmission, although research indicates that SARS does not transmit as easily from person-to-person as more common diseases like the cold or flu. The disease spread most rapidly among healthcare workers and family members of infected individuals. Evidence indicates that the virus also is spread through contact with inanimate objects contaminated with virus-containing secretions. Recent detection of a related coronavirus in wildcat species in China raises concerns that SARS may continue to have an animal reservoir, which would complicate control efforts.

Symptoms. SARS can progress rapidly from fever and cough to serious pneumonia after an average four-to-six-day incubation period, with up to 20 percent of patients needing mechanical ventilation to survive. In some patients, progression to pneumonia may be delayed. Death may occur several weeks to months after initial symptoms.

Diagnosis. Accurate, rapid screening diagnostic tests for SARS are being developed but are not yet licensed in the United States. During the epidemic healthcare workers generally relied on clinical symptoms for detection. WHO defines a suspected SARS case as someone with a temperature over 38° Celsius, a cough or difficulty breathing, and one or more of the following exposures: close contact with a person who is a suspect or probable SARS case, or someone who has lived in or visited a region with SARS transmissions. A “probable case” is a suspected case with radiographic evidence of pneumonia or positive laboratory tests that may take days to weeks to complete.

Treatment. No proven therapy is available for severe SARS pneumonia cases. Most clinicians employ respiratory support, antibiotics, fever reduction, and hydration. Some Chinese doctors have used steroids and the antiviral drug ribavirin with varying degrees of success.

Fatalities. Although the overall lethality of SARS is higher than initially believed, most deaths continue to be among older patients and those with underlying health problems, such as diabetes or hepatitis B. The WHO reported in May 2003 that death rates vary substantially by age:

Preliminary reports on nonfatal cases showed SARS patients required longer hospital stays—an average of three weeks for those under 60 years of age—than patients with other typical respiratory viruses, raising the economic costs of the SARS outbreak. Moreover, preliminary evidence suggests that some people who survive SARS could suffer long-term respiratory damage that increases health complications and costs.

Even though checks of passengers at airports were relatively effective at keeping infected people off airplanes, some lapses did occur.

Quarantines and Isolation12

As SARS spread and political and economic stakes rose, countries took tougher measures to contain it. Some countries resorted to strong steps, such as closing schools despite the low number of cases among children, probably to compensate for weaknesses in their health-care infrastructure. Open societies seemed to have trouble enforcing quarantine orders.

BOX 5-4The World Health Organization: Playing Fairly Well with a Weak Hand

The World Health Organization (WHO) issued an international health warning on SARS in March 2003 and travel advisories regarding particular regions hit by the disease. The WHO, in collaboration with the U.S. Centers for Disease Control and Prevention (CDC) and other organizations, worked to identify the cause of the disease, assisted local investigators, and provided guidance on control measures.

The SARS experience highlights the bureaucratic and technical limitations WHO faces in trying to identify and control the international spread of infectious diseases. Under existing international health regulations, countries are only required to report to WHO outbreaks of yellow fever, cholera, and plague. With these diseases, WHO, the United Nations, and domestic officials have the authority to intervene and prevent the movement of people and goods to avert cross-border transmission. With other diseases, WHO plays an advisory role, including issuing travel advisories and offering advice to member governments on screening procedures. Unless a country invites in WHO investigators, WHO has a limited ability to respond to outbreaks. Moreover, WHO has limited capability to investigate suspicious outbreaks before a country officially reports them.

BOX 5-5The World’s Quick Response to SARS

Several factors appeared to facilitate a faster international reaction to SARS in comparison to other diseases in recent decades.

Fear and Uncertainty. The rapid geographic spread of the mysterious illness created a sense of urgency to respond to a disease that seemed able to “go anywhere and hit anyone.”

Stronger Leadership. The World Health Organization took a more public, activist stance in sounding the alarm and mobilizing the global response.

Scientific Advances. New tools and techniques allowed researchers better and faster ways to study everything from patterns of lung damage to the genetic sequence of the coronavirus.

Heightened Awareness of BW Threat. Concerns about the threat posed by biological weapons enhanced the ability and speed of many countries to identify new infectious diseases.

Concern About Missing “Another” AIDS. Some health officials acknowledge they reacted more quickly to SARS partly due to fears that the world’s slow response in the 1980s to the emergence of HIV/AIDS allowed the disease to build up devastating momentum.

Sometimes the most effective isolation and quarantine policies raised concerns about political freedom and human rights. For example, India and Thailand at one point isolated foreign visitors from countries that had SARS outbreaks, even though they did not have symptoms or known exposures.

Political Leadership

A key variable in managing the SARS epidemic was the willingness of political leaders to raise public awareness of the disease, focus resources, and speed the government response. As noted above, Vietnamese leaders promptly acknowledged the SARS threat at an early stage in the outbreak and sought international help. In contrast, China’s political leaders clearly exacerbated the situation by initially suppressing news of the disease.

Reasons to Stay on Guard

Despite the downturn in cases, SARS has not been eradicated and remains a significant potential threat. Senior WHO officials and many other noted medical experts believe it highly likely that SARS will return. SARS, like other respiratory diseases such as influenza, may have subsided in the northern hemisphere as summer temperatures rise, only to come back in the fall.

No Reliable Screening Tests

Diagnosis remains almost as much an art as a science as long as no proven screening test has been developed. Diagnostic kits currently under development can catch only about 70 percent of SARS cases, and their utility for widespread deployment is not yet known. SARS is difficult to detect, particularly in the early stages, even for countries with the most modern medical capabilities, raising the risk that healthcare workers will miss mild cases. Moreover, there is little prospect of a vaccine in the short-term.

Various countries have different definitions of suspected and probable cases and have changed the definitions over time.

SARS Could Mutate

Natural mutations in the coronavirus which causes SARS could alter basic characteristics of the disease, but whether a mutation would make SARS more or less dangerous is impossible to predict. A significant increase in the transmissibility or lethality of SARS obviously would pose greater health risks and raise fears around the globe.

Difficult to Maintain Vigilance

The willingness of healthcare workers to serve in the face of significant infection risks has been a key variable in the battle against SARS and other emerging diseases. Most healthcare workers in countries hit by SARS toiled long hours under dangerous conditions. The rate of infection among hospital workers was much higher than among the general public, underscoring the difficulty even professionals had in maintaining stringent infection control procedures.

Some health workers refused to work in SARS wards. This problem is likely to grow in both rich and poor countries if the disease resurges.

Shortages in trained healthcare personnel were exacerbated when many healthcare workers fell ill to SARS and were replaced by workers with less training.

SARS Scenarios

Faced with these uncertainties, we have constructed three scenarios to consider potential trajectories for the disease and the implications for the United States. We have not attempted to identify a most likely scenario because the future course of SARS will depend on a host of complex variables, including the scope of present infections, mutations in the virus, the vulnerability of host populations, how individuals and governments respond, and chance.

Scenario One: SARS Simmers

SARS could resurface this fall but be limited to random outbreaks in a few countries. Rapid activation of local and international surveillance systems and isolation procedures would be key to identifying suspect cases and containing the spread. Initially, some cases might elude detection by hospital workers and airport personnel, who have relaxed screening procedures since the disease ebbed. Smaller, poorly funded transit facilities would remain vulnerable because they lacked trained staff and equipment to effectively monitor all passengers.

Some countries would be tempted to hide a resurgence. China’s experience demonstrated that hiding an outbreak is increasingly difficult and costly in a globalized world, but some governments still probably calculate that transparency also has drawbacks. Indeed, the economic repercussions of WHO travel advisories for SARS probably reinforce the incentives countries have to hide or under-report cases.

Even if new SARS outbreaks were sporadic and small-scale, economic, political, and psychological ripples would occur. China faces the biggest risks. Although foreign investors are unlikely to withdraw substantial amounts of FDI, firms with considerable exposure to China might redirect a percentage of new investment to other locations to diversify their manufacturing operations. Companies that already have temporarily shifted some production outside China probably would establish more permanent arrangements.

Multinationals also are likely to become more concerned about the “SARS tax” on their businesses, including increased healthcare expenditures for expatriate employees and expanded insurance to cover the risk to operations and personnel from infectious diseases. Some firms probably would calculate that the risks of frequent business travel outweighed the costs and switch to teleconferencing, telecommuting, and e-commerce.

Paradoxically, keeping SARS out of the United States might become more difficult as fewer cases are seen, because health, transportation, and security workers are more likely to drop their guard in monitoring for infected people if only a few cases pop up now and then.

Scenario Two: SARS Spreads to Poor Countries, Regions

SARS could gain a foothold in one or more poor countries, potentially generating more infections and deaths than before but with relatively little international economic impact. Few poor countries have had SARS appear on their doorstep up to now because most have relatively few links to the affected regions, but the longer the disease persists the more likely it is that SARS will spread more widely.

Most poor countries would have trouble organizing control measures against SARS, especially if the disease gained momentum before it was identified by healthcare workers. Most countries have inadequate hospital facilities to effectively isolate large numbers of patients, and most hospitals even lack the resources to provide food and care to patients.

The spread of SARS into various poor countries is likely to significantly disrupt local economies while having relatively little impact on broader international markets.

The spread of SARS to poor countries also would complicate international efforts to control the disease.

The spread of SARS to countries with weak healthcare systems and vulnerable populations also is likely to make the disease appear more transmissible and lethal, heightening public fears in other parts of the world:

An outbreak of SARS in poor countries would pose particular challenges for the United States and other governments and multilateral organizations providing assistance. WHO and CDC probably would come under pressure to provide money and technical assistance to compensate for weak healthcare systems. The higher the number of infected people, the more the international community would be called on to do something.

Scenario Three: SARS Resurges in Major Trade Centers

SARS could stage a comeback this fall in the main places it hit before—such as China, Hong Kong, Taiwan, and Canada—or gain a foothold in other places with extensive international travel and trade links like the United States, Japan, Europe, India, or Brazil.

Even if the number of infected persons were not greater in a second wave, an outbreak of SARS in major trade centers again would be likely to have significant economic and political implications. The resurgence of SARS in Asia probably would cause less disruption as citizens, companies, and governments learn to live with it, as they do with other diseases, unless the transmissibility or lethality rose substantially. Nonetheless, a second wave of SARS in Asia probably would prompt some multinationals to modestly reduce their exposure to the region if they concluded that SARS posed a long-term health challenge.

A substantial decline in China’s manufacturing sector would reverberate in Southeast Asian economies that provide critical manufactured inputs, raw materials, and energy and disrupts production chains throughout East Asia.

Bigger outbreaks in places such as Europe and the United States would affect new sets of business and government players. The level of public fear almost certainly would be higher in places that had not been affected by the first wave of SARS, driving up social disruption and economic costs.

Even the health systems of rich countries could be overwhelmed if the resurgence of SARS cases coincided with the annual influenza epidemic this winter. As long as no quick and reliable test to diagnose SARS exists, people with fevers and a cough could overwhelm hospitals and clinics as healthcare workers struggled to distinguish patients with SARS and isolate them from others.

Given the high economic and political stakes already seen in the SARS epidemic, some jurisdictions probably would try to fudge health data in an effort to avoid official health warnings or get them lifted more quickly.

Building Better Defenses Against Disease

The emergence of SARS has sparked widespread calls for greater international surveillance and cooperation against such diseases. SARS has demonstrated to even skeptical government leaders that health matters in profound social, economic, and political ways.

BOX 5-6Influenza: Lurking Killer

Influenza is an ideal virus for worldwide spread (a pandemic) and many epidemilogists argue that the world is “overdue” for a major influenza pandemic. When a new type of flu virus emerges from a reassortment of animal and human viruses to which humans have no prior immunity, a pandemic may ensue. Scientists believe the past two influenza pandemics originated in China where people live in close contact with birds and swine, the major sources of animal flu viruses. Influenza spreads even more quickly than SARS because flu can be transmitted efficiently through the air. As a result, close contact is not required for people to become infected, making it almost impossible to trace and isolate ill people who are spreading the disease.

Three major flu epidemics stand out in modern U.S. history:

This intense focus on SARS has opened a window of opportunity to pursue bilateral and international cooperation against infectious diseases. The United States and WHO may be able to develop new institutional channels to foster long-term cooperation on health issues.

Areas of Need

Several countries already are seeking assistance from the WHO and the U.S. CDC in an effort to strengthen their health systems. Some even are moving to commit more resources.

Surveillance

Despite substantial progress in recent decades in building networks to monitor disease, the surveillance systems in most countries remain weak. Many surveillance systems have been built over the years to detect specific diseases, such as polio and guinea worm. The WHO also has created a global network of over 100 centers in 83 countries to track influenza. The longer-term challenge is to build networks throughout countries and regions and the means to issue warnings to national and international authorities.

BOX 5-7Health Surveillance and Biological Weapons

The SARS outbreak illustrates the difficulty in distinguishing the emergence of new infectious disease from the release of a BW agent. Ongoing efforts to improve global health surveillance, however, probably will aid international monitoring for detecting the possible release of biological warfare agents, especially traditional types. As baselines for natural diseases are established in the coming years, a deliberate release of traditional BW agents could be more readily recognized. Unfortunately, many developing countries probably will not acquire domestic detection capabilities, such as tools to identify genetic sequences in disease organisms. Moreover, history suggests that some countries will not support internal disease surveillance efforts for political or economic reasons, leaving significant gaps in a global surveillance system.

Epidemiological Expertise

Many countries lacked trained experts to map the trajectory of SARS. Such expertise was critical to understanding the transmissibility, lethality, and scope of the disease.

Laboratory Facilities

Few countries have the sophisticated laboratories or trained personnel to do the hard science of cracking mysterious new illnesses. As a result, regional or mobile labs may be the most viable prospect for speeding up diagnoses and research.

BOX 5-8SARS and HIV/AIDS

SARS has focused greater international attention on the importance of health, but the new disease probably will not lead to a significant boost in the fight against HIV/AIDS in the coming years. Indeed, many countries are likely to view spending on diseases like SARS and HIV/AIDS as a zero-sum game in the short term.

China’s new health minister has said she plans to focus on HIV/AIDS now that SARS has subsided, according to press reports. Some AIDS activists and NGOs within China also have expressed hope that the government response to SARS will translate into more action on HIV/AIDS.

A resurgence of SARS this winter could delay activity on AIDS, and some AIDS activists in China fear the government might believe the stringent controls used to fight SARS should be used against HIV/AIDS as well.

Equipment

The cost of basic diagnostic and protective equipment is relatively modest yet still unaffordable for many countries. SARS highlighted a widespread shortage of ventilators to support patients with pneumonia. The lack of adequate sterilization equipment raises the risk of spreading disease when medical instruments are reused.

Developing Countermeasures

Progress in developing diagnostic tests, treatments, and vaccines would fundamentally improve prospects for combating SARS. This will take time, however, and first-generation products often are not completely effective without further research and improvement.

Political Hurdles

Almost all countries will express support for improving international healthcare capabilities, but negotiations are likely to be contentious, and many players will see this as an opportunity to win concessions or score points with Washington. Some areas of possible contention are: