The Origins of an Epidemic
The Origins of an Epidemic
In most of the world, AIDS was not recognized as a problem in its own right until around 1981—decades after the disease first arose in humans. Scientists now think that AIDS became evident in humans as early as the 1950s, in Europe and Africa, although proper diagnoses were not made at the time. Since AIDS escaped detection for so long, it is impossible to say how many people died of AIDS-related illnesses in the years before doctors became familiar enough with the disease to identify it in patients. In fact, before 1981, most people had never even heard of the disease—and no one understood how it killed.
Awareness of a looming epidemic was growing rapidly by the end of 1982. Over sixteen hundred cases of AIDS had been diagnosed in the United States; over six hundred Americans had died of the disease. Because of the increased awareness and the evident threat to public health, major initiatives were quickly taken to increase understanding of AIDS and to improve diagnostic techniques. Doctors at the federal government's Centers for Disease Control and Prevention (CDC) worked to track and understand the progression of the disease in individual patients. The goal was to recognize symptoms of AIDS, thereby helping with diagnosis. In addition, scientists worldwide sought to isolate the microorganism that causes AIDS and to develop an effective blood test for diagnosis.
In the United States, awareness of the AIDS epidemic can be traced back to a 553-word article, simply titled "Pneumocystis Pneumonia—Los Angeles." The article appeared in the June 5, 1981 issue of theMorbidity and Mortality Weekly Report (MMWR), the CDC's weekly newsletter aimed at informing health care professionals of current medical concerns. The report did not mention a previously unknown virus; instead, authors Dr. Michael Gottlieb and Dr. Wayne Shandera wrote:
In the period October 1980–May 1981, 5 young men, all active homosexuals, were treated for biopsy-confirmed Pneumocystis carinii pneumonia (PCP).… The fact that these patients were all homosexuals suggests an association between some aspect of a homosexual lifestyle or disease acquired though sexual contact and Pneumocystis pneumonia in this population.4
Gottlieb's and Shandera's patients were dying, apparently of PCP, even though PCP was a generally treatable disease that seldom proved fatal. The patients showed other strange symptoms as well: swollen lymph nodes, fevers, weight loss, oral yeast infections, and elevated levels of cytomegalovirus (CMV), a virus that normally causes no adverse symptoms but which in these patients seemed to overwhelm the body. In addition, these patients suffered from reductions in counts of T cells, which are vital for the immune system's proper function.
In the ensuing months, more cases of strange sicknesses among homosexual men were reported. In addition to cases of PCP, doctors saw young men in their twenties and thirties suffering from a rare skin cancer called Kaposi's sarcoma (KS). Many doctors conjectured that the unusual illnesses were linked in some way, and the CDC issued a warning to physicians: "Physicians should be alert for Kaposi's sarcoma, PC pneumonia, and other opportunistic infections associated with immunosuppression in homosexual men."5 By the end of 1981, 422 cases of the syndrome, that is, a group of symptoms that collectively characterize a disease, were reported in the United States alone, with 156 people dead—and still, no one knew the cause.
Following the Trail
When the CDC began studying the syndrome, it became immediately clear that a hallmark was a loss of immune function that allowed the development of opportunistic infections—illnesses that would have never occurred had the immune system been functioning properly. More and more patients were diagnosed with the same strange maladies: yeast infections, toxoplasmosis (a rare parasitic disease that usually causes no negative symptoms in healthy people), infections from cryptococcosis (a fungus commonly found in bird droppings), CMV infections, as well as KS and PCP. A whole host of other rare illnesses were also soon added to the list. Doctors reported patients afflicted with the syndrome were showing signs of diseases as exotic as feline leukemia, a major cause of death in cats, and cryptosporidiosis, a parasitic disease usually seen only in sheep and goats. It appeared that these patients' immune systems were so compromised that microorganisms usually unable to infect humans at all were able to create life-threatening infections.
Another seemingly consistent feature was that the syndrome appeared to affect only homosexual men; in fact, it seemed that the more promiscuous the subject, the more likely he was to become infected. In a New York Times article, Dr. James Curran of the CDC stated that heterosexual men and women, regardless of sexual orientation, were apparently safe from the syndrome: "The best evidence against contagion is that no cases have been reported to date outside the homosexual community or in women."6 With this assumption in mind, in January 1982, the syndrome was named gay-related immunodeficiency disease, or GRID.
Doctors at the CDC looked for connections between the victims of GRID, in an effort to establish the disease's mode of transmission. From interviewing victims, they were soon able to establish social and sexual connections between people who later developed symptoms of GRID. Of the first nineteen cases of GRID investigated, sexual links were confirmed between nine of them. The suspicion arose that whatever was causing GRID was transmitted sexually.
Cancer, a Virus, and GRID
Scientists already knew that certain infections could result in immune suppression; moreover, there were viruses that had been identified that did just that. Certain cancers had also been linked to viral infections, and these cancers sometimes interfered with proper immune function. For example, the human T cell leukemia virus (HTLV) had been shown in 1980 to be a cause of T cell leukemia in Japan and the Caribbean. Patients with T cell leukemia, like those with GRID, experienced severe drops in T cell counts.
Some researchers at the CDC supported the notion that GRID also was caused by a virus. This had ominous implications: Viruses do not consider sexual orientation when they infect a host. If a virus was causing GRID, there was no reason to believe that the contagion would stay confined to the relatively small population of homosexuals. Scientists predicted that the epidemic would soon spread to people outside the gay community.
Drug Addicts, Hemophiliacs, and Children
The prediction turned out to be correct. As early as mid-1981, doctors had noticed symptoms in intravenous drug users that in hindsight were consistent with GRID. By early 1982, at least twenty-three heterosexuals, mostly intravenous drug users, were counted among GRID victims.
Many scientists felt that the infections seen in intravenous drug users suggested that GRID could be spread through the blood as well as through sexual contact, and that it was more likely to have a viral cause. Since intravenous drug users often shared needles, they were exposed to the blood of other drug users. This means of disease transmission was well known. The blood contact spread diseases such as hepatitis B, which was caused by a virus.
The theory that GRID was spread through blood contact got further corroboration when a number of people with hemophilia began showing symptoms. Hemophiliacs, who have a blood disorder that prevents proper clotting following injury, often require transfusions and injections of the components their own blood lacks. In early 1982 in Miami, an elderly man with hemophilia was diagnosed with Pneumocystis. He was not an intravenous drug user, but because of the hemophilia, he received regular injections of a clotting agent. The clotting agent, isolated from the blood of nonhemophiliac blood donors, is called Factor VIII.
The man's doctor initially believed that Pneumocystis carinii microorganisms might have contaminated the patient's doses of Factor VIII. Bruce Evatt at the CDC, however, assured the physician that these bacteria were large enough that they would have been completely filtered out during the process of Factor VIII isolation. Only very small microbes, such as viruses, could pass through the filtering process.
The number of nonhomosexual GRID cases continued to rise. By mid-1982, two more hemophiliacs were confirmed to have GRID. Infected intravenous drug users were also becoming more common. Furthermore, there were reports of children of GRID-infected drug addicts showing GRID symptoms from birth. One account told of a seventeen-month-old baby who had oral yeast infections, staphylococcus aureus infections, and an infection of a bacterium called Mycobacterium avian-intracellular, which was usually only seen in birds. Another thirty-week-old infant was suffering from infections including PCP, cryptococcosis, and CMV—all hallmarks of GRID. Soon, doctors at the CDC were forced to conclude that GRID was not purely a homosexual disease. Furthermore, the fact that babies could be born with the disease made it clear that, although lifestyle was a risk factor, virtually anyone could contact GRID. As this fact became clear, scientists redoubled their efforts to find the cause of GRID.
A New Name and a New Fear
In light of the new information regarding who was at risk, the name "gay-related immunodeficiency disease" seemed inappropriate. Curran argued that a more neutral name should be given to the disease. He later recalled, "By now there had been reports of cases in injecting drug users, and in women who were sex partners of men with AIDS, so it was time to describe it more broadly."7 After some discussion, a new name was proposed: "acquired immune deficiency syndrome," or AIDS. The new name implied a greater risk for the population at large, and more of the public began to take interest in the AIDS situation.
Much of the interest was sparked when a new source of fear concerning AIDS was identified: Blood banks could and had been providing infected blood to unsuspecting patients. The first known case of transfusion-related infection came in 1983, when a fifty-three-year-old man was diagnosed with AIDS. He was not a homosexual, an intravenous drug user, or a hemophiliac, but he had undergone open-heart surgery twenty-nine months before the diagnosis. During his surgery, doctors had given him blood transfusions.
When more transfusion recipients—thirty-nine of them by the end of 1983—began showing AIDS symptoms soon after they had received blood, the list of who was at high risk for contracting AIDS was greatly expanded. Dr. Harold Jaffe of the CDC described the situation: "When it began turning up in children and transfusion recipients, that was a turning point in terms of public perception. Up until then it was entirely a gay epidemic, and it was very easy for the average person to say 'So what?' Now everyone could relate."8
It became more difficult to argue that AIDS was not in the blood. Yet even though the medical evidence suggested that AIDS could be transmitted through blood contact, there was still a great deal of resistance to that theory, especially from the blood banks, many of which sold blood for a profit. If blood banks admitted that their product might be infected, there would be serious financial repercussions for the entire industry.
The problem was having no way to test blood for a microorganism that had not yet been identified. As a stopgap measure, in 1983, the CDC proposed that blood products be tested for hepatitis B, citing the fact that an overwhelming number of people in the highest risk groups for AIDS—gay men, hemophiliacs, and intravenous drug addicts—had also at some point contracted hepatitis B. In fact, 88 percent of homosexual AIDS patients, 80 percent of hemophiliac AIDS patients, and virtually 100 percent of intravenous drug–addict AIDS patients tested positive for hepatitis B. Removing hepatitis B–positive blood from the supply could therefore be expected to reduce the risk of a recipient contracting AIDS.
The blood-banking industry, however, rejected the plan outright. Dr. Aaron Kellner, president of the New York Blood Center, stated that the cost of testing was prohibitive; he estimated the national cost to perform hepatitis B tests would be $100 million annually. He contended that the small number of AIDS cases that resulted from tainted blood was not enough to justify such an expensive course of action: "We must be careful not to overreact. The evidence [that the blood supply may be seriously tainted] is tenuous."9
The Virus Hunt
With the increase in the number of people perceived to be at risk for contracting AIDS, scientists both in the United States and elsewhere knew that answers to the fundamental problems of the epidemic—what causes AIDS and how doctors could diagnose the disease before a victim spreads it—had to be found, and quickly. Researchers at the National Institutes of Health (NIH) in Bethesda, Maryland, and at the Pasteur Institute in Paris followed seemingly unrelated trails in search of the virus that caused AIDS.
At NIH, Dr. Robert Gallo headed the team that was hunting for the AIDS virus. Gallo was an expert in retroviruses, a class of virus whose genes are stored, not as deoxyribonucleic acid (DNA), but as ribonucleic acid (RNA), another type of genetic material. He had identified the only two retroviruses scientists knew of, HTLV-1 in 1979 and HTLV-2 in 1982, both of which were involved in human T cell leukemia. Since that disease also greatly affected T cells, Gallo had long contended that AIDS was also caused by a retrovirus, similar to HTLV-1 and HTLV-2. Despite this promising theory, Gallo and his team had made very little progress in actually identifying the cause of AIDS. By early 1983, they had examined blood samples from thirty-three AIDS patients but had found HTLV-related genetic material in only two of them.
A Major Breakthrough
In the meantime, scientists at the Pasteur Institute had experienced greater success. Dr. Luc Montagnier was in charge of the AIDS research effort at the Pasteur Institute. Using a tissue sample from a French AIDS patient, Montagnier attempted to grow the AIDS virus in a laboratory culture of human T cells. Fifteen days later, the cell culture showed traces of a protein called reverse transcriptase that is used by retroviruses when they proliferate in host cells.
Montagnier was able to isolate the virus from the tissue sample and compare it to other previously identified retroviruses. He was sure that the AIDS patient's virus was different from anything seen before. In May 1983, Montagnier announced his discovery of the AIDS retrovirus, which he later named lymphadenopathy-associated virus (LAV). Montagnier, however, was not able to prove conclusively that LAV actually caused AIDS. Gallo's group, meanwhile, had finally isolated a retrovirus they called HTLV-3 in the blood of AIDS patients. In 1984, they were able to demonstrate a strong correlation between its presence and the onset of AIDS symptoms.
It was eventually shown that LAV and HTLV-3 were the same virus. Since both research teams had worked on the discovery and made important contributions, Gallo and Montagnier agreed to share credit for discovering the virus that causes AIDS. Rather than choose between the names LAV or HTLV-3, in early 1987, an international committee renamed the organism human immunodeficiency virus, or HIV.
By the time the AIDS virus was renamed HIV, a number of scientists had developed tests to screen for its presence in blood samples. These tests were slightly different from each other, and none detected the virus itself; rather, they detected the presence of antibodies to HIV, which the immune system creates in response to exposure to the virus.
The newly developed HIV tests were widely used to screen readily available blood bank samples as well as individuals concerned that they might have contracted HIV. In 1985, after the U.S. Food and Drug Administration (FDA) approved a blood-screening test for HIV, the American Red Cross reported that one in five hundred American blood donors was a carrier of HIV. Even more alarming, because millions of people had received blood tranfusions since the beginning of the AIDS epidemic until the time testing became routine, thousands of transfusion recipients were unknowingly carrying—and transmitting—the disease. The situation elsewhere was even more alarming. That same year, for example, random samples of blood from seventy-five hundred Parisians were screened for HIV antibodies. The study found that one in two hundred people was infected with HIV. Furthermore, an estimated fifty additional infections were occurring every week in hospitals through infected blood.
When the blood-banking industry finally agreed to a "look back" program in April 1986 to identify people who had previously received AIDS-infected blood, the statistics were terrifying to the public. In the final weeks before blood banks began using the HIV test to screen samples, 150 infected donors gave blood that was transfused into 200 unsuspecting patients. In addition, studies revealed that the rate of HIV infection among homosexual men ranged between 10 percent in areas such as New Mexico to 70 percent in areas such as San Francisco or New York City. The CDC also estimated that 25 percent of the approximately 900,000 intravenous drug users were infected with HIV. Overall, the national estimates of Americans carrying HIV ranged from previous figures of 500,000 to 1 million people to approximately 2 million.
The concern felt by the American public grew with the new statistics, but CDC and Health and Human Services officials sought to allay fears by reiterating that the highest risk of contracting HIV was limited to the described risk groups: homosexual men, intravenous drug users, hemophiliacs, and transfusion recipients. Heterosexuals who did not use intravenous drugs, or did not have sex with people in the described risk groups, were still considered to be at low risk. According to Dr. Otis Bowen, secretary of Health and Human Services in 1987, "There is not an [AIDS] epidemic among heterosexuals, as some people think."10 Bowen, however, was mistaken. HIV could be transmitted by any sexual intercourse. Heterosexual individuals who had unknowingly contracted HIV were, in fact, able to transmit the disease. In this way, AIDS was spreading silently through the mainstream.
Though the HIV test provided valuable information that would help prevent the spread of the disease, it did nothing to relieve the suffering of HIV patients; their symptoms continued, irrespective of confirmation from the blood test that they only carried the virus. In fact, the test was often detrimental to these patients' quality of life. As Gallo explained, "We'd see reminders in the faces of all the infected people that we'd done nothing for them. I'd say: 'We have a blood test now.' That was a life-saving public health advance, but they'd say: 'What's a blood test to me—it only defines me as infected.'"11 With the tools in place to identify patients with HIV, the next steps in the AIDS crisis were to gain an understanding of the disease and to find effective treatments, and perhaps even cures.