The degradation of language is a luxury. After the end of the Cold War, and with it the threat posed by the Soviet Union, Americans could afford to loosen their definition of what constituted a "vital security interest." During the 1990s, quite optional interventions around the world, from Kosovo to Somalia, were all declared to serve "vital U.S. interests." This happy linguistic fuzziness persisted until September 11 reminded us what a real "vital interest" looked like. Severe Acute Respiratory Syndrome, or SARS, may prove to be the 9/11 of public health.
The meaning of "public health," too, has sprawled out lazily over the decades. Once, it referred to the project of securing health benefits that were public -- clean water, improved sanitation, and the control of epidemics through treatment, quarantine, and immunization. Public health officials worked to drain swamps that might breed mosquitos and thus spread malaria. They strove to ensure that water supplies were not contaminated with cholera, typhoid, or other diseases. The U.S. Public Health Service began as the Marine Hospital Service, and one of its primary functions was ensuring that sailors didn't expose domestic populations to new and virulent illnesses from overseas.
Those were legitimately public health issues because they involved consumption of a collective good (air or water) and/or the communication of disease to parties who have not consented to put themselves at risk. It is difficult for individuals to protect themselves against illnesses found in air, water, or food. A breeding ground for disease-carrying insects poses a risk to entire communities.
Plenty of people in Africa and Asia still need those basic public health measures. As Jerry Taylor writes in Regulation magazine: "Diseases associated with inadequate sanitation, indoor air pollution from biomass stoves and furnaces, and contaminated water occur mainly in developing countries and account for 30 percent of the total burden of disease in those nations. Diarrheal diseases, brought on by poor sanitation and contaminated water, alone kill more than three million children annually, and experts believe that two million of those deaths could easily be prevented with even minimal improvements in sanitation and water quality. Approximately seven million die each year from conditions like tuberculosis, cholera, typhoid, and hookworm that could be inexpensively prevented and cured and are virtually unknown as serious health problems in advanced countries."
In the United States and other developed countries those public health problems have been largely solved. For instance, in the 1920s there were 13,000-15,000 reported cases of diphtheria each year in the United States. Only one case was reported each year in 1998, 1999, and 2000. Before 1963, there were about 500,000 cases of measles and 500 measles deaths reported each year. A record low annual total of 86 cases was reported in 2000.The last cases of smallpox on earth occurred in an outbreak of two cases (one of which was fatal) in Birmingham, England in 1978, almost 30 years after the last case in the United States.
But bureaucracies are notoriously unwilling to become victims of their own success. So, true to form, the public health authorities broadened their mandate and kept on going. They launched informational and regulatory crusades against such health problems as smoking, venereal disease, AIDS, and obesity. Pick up any newspaper and you're apt to find a story about these "public health crises." Those are all health problems, to be sure, but are they really public health problems? There's an easy, perfectly private way to avoid increased risk of lung cancer and heart disease. Don't smoke. You don't need any collective action for that. Want to avoid AIDS and other sexually transmitted diseases? Don't have sex, or use condoms. (The threat to the blood supply did have public health aspects and was dealt with promptly.) As for obesity, it doesn't take a village for me to eat less and exercise more.
Language matters. Calling something a "public health problem" suggests that it is different from a personal health problem in ways that demand collective action. And while it doesn't strictly follow, either in principle or historically, that "collective action" must be state action, that distinction is easily elided in the face of a "public health crisis." If smoking and obesity are called public health problems, then it seems that we need a public health bureaucracy to solve them -- and the Public Health Service and all its sister agencies don't get to close up shop with the satisfaction of a job well done. So let's start using honest language: Smoking and obesity are health problems. In fact, they are widespread health problems. But they are not public health problems.
Now, however, we are confronted with a new old-fashioned public health problem. SARS and AIDS are both caused by a virus, but they spread in different ways. To become infected with HIV, the virus that causes AIDS, you have to have intimate contact with an infected person. The SARS virus, it appears, can be spread through the air and even on doorknobs. Already, some 7,000 people have been infected with the disease, more than 5,000 in China alone, and over 500 are known to have been killed by it. The World Health Organization originally put the fatality rate for SARS at about 7 percent, but has recently raised its estimate to 15 percent. Of those above 65 who become infected, fewer than half can expect to survive. To put this in perspective, consider that in one of the worst malaria epidemics of the 20th century, 3 million people in Sri Lanka contracted the disease in 1934-35. Only three percent, about 80,000, died. The potential for death if the far more fatal SARS should become as widespread is staggering.
Doctors are working overtime to find out more about SARS. But until we know more, we need some protection. And the only way we can protect ourselves from SARS at this time appears to be to quarantine SARS carriers. We can't allow jet-age Typhoid Marys to walk around threatening infection with every breath and every touch. Quarantine is a step that should only be carried out with great caution, and with appropriate safeguards for due process, but it appears to be necessary. Because the disease is so contagious, each case truly poses a problem for the public, not merely the individual infected.
In the short term, the most pressing demand on public health authorities will be to find a quick and effective way to halt the spread of this epidemic without impinging on civil liberties more than is necessary to protect people. But SARS should also prompt us to reflect more broadly on what those authorities do, and why they do it. The need for a collective response to the threat of SARS should throw into sharp relief the crusades against purely private ailments that have begun to occupy a central place in "public health." Our scarce public resources should be devoted to fighting those health problems that only collective action can address, rather than hectoring the citizenry for its bad habits. The government will have its hands full stopping the spread of SARS. It can leave the task of cutting down on Marlboros and Big Macs to us civilians.