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Last Updated

04 May 2003

Source: Newsday, May 4, 2003


The SARS Epidemic

The Next Intervention; The U.S. should lead the charge on global disease

By Barry R. Bloom

Barry R. Bloom is dean of the Harvard School of Public Health in Boston and professor of immunology and infectious diseases.

It took enormous courage for the World Health Organization to declare on March 15 a global alert for the first time in its history, and caution against travel to countries with outbreaks of SARS (Severe Acute Respiratory Syndrome). That message galvanized the world to prepare for a deadly respiratory infection and gave us all an early warning.

We know from history that other infections transmitted by respiratory droplets can have devastating effects - the 1918 influenza pandemic killed 20 to 40 million people worldwide, the introduction of measles into Hawaii in the 18th century decimated the population, and tuberculosis continues to infect 8 million people each year and take 2 million lives. Respiratory infections must be taken seriously; one person can spread it to many.

It has been argued, by Canadian health officials and others, that WHO is overreacting: that the number of SARS cases and deaths is still relatively small, compared, for example, to the injuries from motor vehicle accidents and gun injuries in the United States. But those numbers are not increasing at a rapid rate, and SARS is. It is much easier to contain an epidemic when the numbers are small than when they become high. Vietnam and Canada did that, and WHO has lifted its travel alerts; China did not, and there are thousands of probable cases and more suspected cases, putting the country's medical capabilities under severe strain.

From WHO's point of view, the situation might be compared to a surgeon's decision on when to excise a cancerous tumor. Given all the uncertainties, is it more prudent to act while the threat to human life is relatively small but growing, or to wait until it is clear and present?

We also know from history that fear of epidemics exacts a toll in both human and economic terms. The anticipated epidemic of plague in India in 1994 that ultimately spread to fewer than 1,000 people devastated tourism and trade and cost India more than $2 billion. The cholera outbreak in Peru in 1996, though contained, cost the country $2 billion as well. And the swine flu epidemic of 1976 that didn't happen cost the director of the federal Centers for Disease Control his job.

But consider this: While it took two years from the recognition of AIDS to the identification of HIV as its cause, WHO created a global SARS network of 13 laboratories, including the Centers for Disease Control, which identified a coronavirus as the causative agent, in two weeks. In two more, the entire genome of the virus was revealed and made available to scientists all over the world. In an extraordinary way, scientists, rather than competing, collaborated and shared their information, which made much of what we now know about SARS possible in record time. From this knowledge, there is hope for a useful diagnostic test and possibly a vaccine.

This is not the first such network created by WHO. In 1952, the agency established an influenza surveillance network, now 87 functional National Influenza Centers in 70 countries. They sample the newly emerging strains of influenza virus, predict the major strains likely to cause disease over the next year and enable companies to produce different flu vaccines every year to protect people here and abroad.

The tools of public health to prevent infectious disease transmission - public alerts, isolation of cases, quarantine of contacts - certainly can cause enormous inconvenience to a small number of people and engender fear in a larger number. Yet SARS shows how early action is crucial to prevent larger numbers of people from becoming ill and massive human and economic losses from an epidemic out of control.

Epidemic threats raise not only medical questions, but questions of values in society. Will individuals be willing to forgo their personal needs to be respectful of the life and lives of their entire community? Will political leaders attack WHO or CDC for recommending travel restrictions, or provide support for those individual sacrifices made for the civic good of the community and nation?

Our security, particularly from infectious disease threats, increasingly depends upon the integrity and expertise of scientists around the world. Strengthening the public health systems in poor countries can provide the best early warning to enable us to prepare for infectious threats. With the same intensity we gave to Saddam Hussein, we could be waging war against global infectious disease by training experts in disease surveillance, strengthening laboratories around the world and linking them to the best labs in the United States, and by supporting the WHO, which is an agency of the United Nations.

The United States has seen only a small number of SARS cases, and they have not spread. Why? Part may be luck, but a substantial part represents public health preparedness that was not in place before Sept. 11, 2001, or Oct. 5, when we first faced outbreaks of anthrax. Funds for bioterrorism have allowed front-line health workers, police and firefighters, as well as physicians and emergency-room personnel, to be trained and rehearsed. Most hospitals now have isolation facilities and respiratory precautions. We are much better prepared than ever, not only for man-made threats, but for unpredictable threats of nature, which remain the most menacing of all biological threats.

The successful response to SARS outside China demonstrates the value of a global health network that will protect our country and every other from the threat of devastating infectious diseases. And in a world distrustful of our values in the United States, investing in global health could help to change our image from one of self-interest to human interest.