PLAYING CHICKEN WITH HUMAN LIVES (CONCLUSION)
Does science matter only when it says what you want to hear?
by Richard Conniff
In June 1962, Rachel Carson’s Silent Spring began to appear in weekly installments in The New Yorker, attacking the uncontrolled use of DDT and other pesticides, and also raising broader questions about blind reliance on technological solutions. Biochemist Thomas H. Jukes promptly responded in Chemical Week with a portrait of a more natural world, in which women had no time to be “writers of science fiction horror stories” because they were too busy “squashing black beetles; beating the clothes moths out of the winter woollens; scraping the mould from the fatback pork; and wondering if they could afford the luxury of a chicken for their Sunday dinner.”
That last line hints that he foresaw the developing attack on the use of antibiotics as growth promoters in livestock. It came just three years later, when a Salmonella strain that was resistant to multiple antibiotics killed six people in the United Kingdom. The British government’s “Swann Report” subsequently concluded that the disease organisms “acquired their resistance through the use of antibiotics in animals.” Jukes responded that this remained to be proved. He seemed worried mainly that the press would now “threaten us with the propaganda device of a new Silent Spring.”
Jukes was a brilliant scientist and polemicist. His friends remember him, on his death in 1999, as “cantankerous” but “usually right and always honest.” They celebrated him as a decent, well-rounded man, who loved to take his family on hikes into the mountains, was a careful reader of the novels of Aldous Huxley, listened to Bach and Beethoven, could quote Shakespeare at will, held season tickets to Berkeley’s “Cal Bear” football games, and, though he had grown up in England, enjoyed few things more than watching Oakland A’s pitcher Dennis Eckersley striking out the other side in the ninth inning of a close game.
An obituary called Jukes “one of the giants of 20th-Century biological science.” He may also have been one of its greatest failures. During the long fight over antibiotics in livestock feed, he always focused on the benefits and minimized the risks. When another deadly outbreak of antibiotic resistant Salmonella occurred in 1985, for instance, he noted in Science that “feeding antibiotics to animals has increased meat production by millions of pounds annually for 30 years.” That was what mattered—feeding a hungry world no matter the cost.
Elsewhere, Jukes often stated that he and his fellow researchers at Lederle had foreseen the danger that feeding antibiotics to livestock would make bacterial strains resistant to antibiotics. But he discounted the idea that antibiotic resistance would spill over to affect human health. Resistance would occur within the guts of animals receiving the antibiotics, and that mattered to him, he suggested around the time of the Swann Report, mainly on the narrow, practical grounds of “whether the effect of antibiotics on improving growth … in farm animals would disappear in a year or two because of the emergence of resistance. If this were the case, we would indeed be doing more harm than good by temporarily alleviating a problem only to replace it with a more intractable one.” Then he added this chilling sentence: "The experiment to provide the answer was under way on a gigantic scale by 1951 and is still in progress.”
Researchers continue to argue today about the consequences of this willy-nilly global experiment, particularly as the medical world’s “wonder drug” antibiotics become ineffective against an array of virulent pathogens, notably including Salmonella, E. coli, MRSA (methicillin-resistant Staphylococcus aureus) and the totally drug-resistant variety of tuberculosis that has so far appeared in India, Iran, Italy, and the United States. Margaret Chan, then-director general of the World Health Organization, warned that we stand on the brink of a “post-antibiotic era.” That could mean “an end to modern medicine as we know it. Things as common as strep throat or a child’s scratched knee could once again kill.” Infections of all kinds caused by resistant strains of E. coli already kill more than 800,000 people each year worldwide.
The livestock industry continues to deny that antibiotics in animal feed bear much blame for this alarming development. (In the five years after the U.S. Food and Drug Administration made use of antibiotics for growth promotion illegal in 2017, sales of livestock antibiotics actually increased.) But evidence increasingly indicates that resistance routinely spills over from food animals to people, in ways we are only beginning to recognize. In one revealing study, the Public Health Agency of Canada monitored the effects when the poultry industry in Quebec briefly suspended use of a standard antibiotic. Levels of resistant Salmonella and E. coli on supermarket chicken promptly dropped. So did resistant Salmonella infections in humans. When use of the antibiotic resumed, resistant bacteria soon reappeared in both meat products and in human consumers.
If he were alive today, Jukes might still deny that turning antibiotics into animal feed had anything to do with this problem. But given his public record, the remarkable thing is that he encouraged the pharmaceutical industry’s “gigantic” experiment to go forward in the first place. In arguing with his critics, he always insisted that they back up their words with hard scientific evidence. But in his own work at Lederle, with his tantalizing new discovery ready to go to market largely untested, Jukes had behaved as if all the rules of basic science somehow did not apply. It was an extraordinary act of hubris. If those who oppose the practice of feeding antibiotics to promote growth in livestock are correct, the terrible consequence is that vast numbers of people now pay for it every year with their lives.