COVER

A SWIFT KILLER

The disease that attacked Lucien Bouchard affects only one person in a million

MARK NICHOLS December 12 1994
COVER

A SWIFT KILLER

The disease that attacked Lucien Bouchard affects only one person in a million

MARK NICHOLS December 12 1994

A SWIFT KILLER

COVER

The disease that attacked Lucien Bouchard affects only one person in a million

MARK NICHOLS

The ordeal began in October, when John Jeffs felt a sharp pain under his right arm. Within a few days, recalls Jeffs, a retirement home administrator in Aurora, Ont., 25 km north of Toronto, “pain and swelling started to move across my chest and up my neck.” Perplexed, local physicians had Jeffs transferred to a Toronto hospital, where doctors diagnosed a severe group A streptococcus infection and, at one point, considered amputating Jeffs’s arm. As the disease spread, Jeffs’s heart and liver were affected; he was put on a life support system. “The skin was coming off his hands and feet in thick chunks,” recalls Jeffs’s wife, Janice. Finally, after 10 days in intensive care, antibiotics halted the infection.

But the damage to the man’s body was extensive, and it was four months before Jeffs, 43, could return to work part-time.

Jeffs was luckier than Lucien Bouchard.

The stunning swiftness with which a similar infection robbed the Bloc Québécois leader of his left leg last week focused attention on necrotizing fasciitis, a disease that is still rare—it affects about one person in a million—but may gradually be growing more prevalent.

Until recently, few people had ever heard of necrotizing fasciitis, the virulent bacterial infection that devours human tissue, or of necrotizing myositis, the variant that attacked Bouchard. The disease gained prominence last May, after it attacked seven people in the English city of Gloucester. And suddenly last week, McDonald at Mount Sinai Hospital in Toronto: Mt is almost a Darwinian balancing act’

necrotizing fasciitis seemed to be everywhere. A day after Bouchard’s leg was amputated, a 24-year-old female student at Newfoundland’s Memorial University died of the disease in St. John’s. Two men died of the disease in California last week, and in Winnipeg, a 46-year-old woman died of it in early November. Doctors are only beginning to learn why some strains of group A streptococcus bacteria wreak such terrible damage on the human body. But they know what the disease can do. Because necrotizing fasciitis destroys human tissue so rapidly, it can inflict fatal damage before antibiotics have had time to stop it.

Some doctors are convinced that the disease is becoming more widespread—but they cannot prove it. The reason: because necrotizing fasciitis is not contagious, most doctors in Canada and the United States are not required to report it. In Ontario, one of the few North American jurisdictions where records now are being kept, officials counted 18 cases over the past two years. So far this year, there have been eight cases in the province. Even if it is increasing, says Brett Finlay, a molecular biologist with the Canadian Bacterial Diseases Network in Vancouver, “with numbers like that,

it’s just peanuts—practically non-existent compared with other serious diseases.”

Necrotizing fasciitis is just one of an array of illnesses that can be caused by a versatile family of more than 70 bacterial strains known as group A streptococcus. Group A strep can cause skin rashes, ordinary sore throats and more serious strep throat, as well as scarlet and rheumatic fever and bubonic plague. In its most virulent forms, group A strep can also induce deadly infections, including a form of toxic shock syndrome—which killed Muppets creator Jim Henson in 1990—as well as necrotizing fasciitis, which starts in the connective tissue between skin and muscle and can go on to attack muscles and organs throughout the body.

When the disease engulfs mainly muscle, as it did in Bouchard’s case, the term necrotizing myositis is sometimes used.

Necrotizing fasciitis can start with a simple cut or even a bruise— anything that breaks the body’s protective barrier of skin and lets the bacteria in. At a news conference following the amputation of Bouchard’s leg, doctors rejected a suggestion that the politician might have picked up the bacteria that caused his illness in Montreal’s Saint-Luc Hospital, where he was treated. But other doctors note that people often acquire infections in hospitals. “Certainly, necrotizing fasciitis can be acquired in a hospital setting,” says Dr. Andrew Simor, a microbiologist at the Sunnybrook Health Science Centre in Toronto.

“Unfortunately, hospitals are not very sterile environments.”

Though few Canadians are likely to be struck by necrotizing fasciitis, there is no way of hiding from the bacteria that cause it. About 15 per cent of all North American children and one in every 100 adults are group A strep carriers, which means that they may carry the bacteria in their bodies without ever becoming ill. And the bacteria can easily jump to a new host through bodily contact or when a carrier coughs and sprays bacteria-laden droplets into the air, where another person can inhale them. Luckily, most of the illnesses caused by group A strep are not life-threatening, and some group A-related diseases appear to be on the wane: scarlet fever, regarded as a serious disease 40 years ago, is now increasingly rare in North America.

But some group A illnesses—including necrotizing fasciitis—may be slowly gaining ground around the world as the result of a cyclical shift in the relationship between bacterial and human populations that scientists do not yet fully understand. The principal villains are two strains of group A strep—dubbed Ml and M3—which cause some cases of severe blood infections and toxic shock syndrome, and are responsible for most cases of necrotizing fasciitis and myositis. “These strains have become more prevalent during the past 10 years,” says Benjamin Schwartz, an epidemiologist at the Centres for Disease Control (CDC) in Atlanta.

No one is sure why Ml and M3 are spreading. But scientists have theories. They speculate that the strains were more prevalent a generation ago than they are now. In those days, Ml and M3 caused the same diseases they cause today (though in the past, some cases of necrotizing fasciitis may have been confused with gas gangrene and

other tissue-destroying diseases). And because Ml and M3 were more prevalent a generation ago, more people encountered them and became immune to the bugs without becoming ill.

As immunity in the human population increased, the theory holds, the bacteria population dwindled. “As we build up immunity, the bacteria population becomes dormant,” says Dr. Kelly McDonald, a medical microbiologist at Toronto’s Mount Sinai Hospital. “It is almost a Darwinian balancing act between the bacteria strains and the human response to them.” Then, as people encountered fewer of the Ml and M3 strains over the years, their immunity declined—and now the opportunistic bacteria may be staging a comeback. Because of the lack of immunity, says the CDC’s Schwartz, “more people become sick and give the bacteria to others. And the bacteria gradually becomes more widespread in the population.” Meanwhile, scientists are beginning to understand the mechanisms that enable the Ml and M3 strains to destroy human tissue so efficiently. Many of the Ml and M3 bacteria are armed with a powerful toxin, or poison, called pyrogenic exotoxin A, which can cause widespread damage by causing the body’s immune system to overreact, triggering a destructive “inflammatory cascade.” As well, Simor has discovered that the Ml and M3 strains possess more proteaze enzymes, which specialize in devouring protein, than other members of the group A family. Equipped with its toxin and protein-eating capability, the Ml and M3 strains can eat rapidly through human tissue. “Once the bacteria gets inside a host body,” says Finlay, “it begins chewing up tissue to get at the nutrients.” In this nourishing environment, the bacteria multiply rapidly and eat their way through tissue at a rate that can destroy as much as an inch of human flesh an hour.

Unlike some other disease-causing bacteria—including the ones that cause tuberculosis and some forms of meningitis—the group A strep have not developed immunity to antibiotics. “Drug resistance,” says Schwartz, “is not a problem.” But the swiftness with which necrotizing fasciitis can destroy human flesh often outstrips the ability of penicillin, the antibiotic most commonly used to contain the disease. Antibiotics, notes Finlay, “can take up to 48 hours to kick in. Necrotizing fasciitis just develops too quickly for it.”

Because necrotizing fasciitis is still extremely rare, trying to avoid it, says McDonald, is “like saying, how can I avoid getting hit by lightning.” Still, there are sensible steps that can be taken. Because even a seemingly trivial infection or skin wound can set the stage for deadly infection, experts advise people to see a physician whenever a cut shows signs of redness or swelling or is accompanied by fever. After witnessing the horrifying speed with which a group A infection destroyed Lucien Bouchard’s leg, many Canadians may make a point of following that advice.

MARK NICHOLS with SHARON DOYLE DRIEDGER