The 'return of our old enemies in an untreatable form'

June 13, 2011 — Before the widespread use of antibiotics, infectious diseases were a major cause of illness and death. Thanks to the drugs, many of those diseases have been brought under control since the 1950s. But the misuse of antibiotics in humans and animals has yielded bacteria that are increasingly antibiotic resistant, and, as reported last week, the agriculture industry in the United States has remained firmly regulation-resistant in the face of calls to reduce or eliminate the non-therapeutic use of antibiotics in animals (for example, antibiotics used for promoting growth).

If the current trend continues, it appears that we are on the threshold of an era in which now-treatable infectious diseases re-emerge as frequent life disrupters, and, ultimately, as major killers (see box).

“We will slowly go back to the situation of the early 20th century when infectious disease was such a scourge that people didn’t live long enough for heart disease and cancer to be our biggest problems,” said Margaret Mellon of the Union of Concerned Scientists.

More complications

One consequence of increased antibiotic resistance is that more people will be more susceptible to life-altering complications from such resistance, such as organ damage, kidney failure, and lung injury, said Brad Spellberg, associate professor of medicine at the UCLA Geffen School of Medicine. He gave the example of a colleague who came down with diverticulitis, an infection of the intestinal lining. That colleague’s doctor gave him the standard antibiotic treatment, but it failed and the infection eroded his colon to the point that a hole was created in the colon wall. He had to have a colostomy bag for several months. “It completely and fundamentally changed his life,” Spellberg said.

Mellon also said she knew a colleague who contracted an antibiotic-resistant infection that did not respond to the first drug she was prescribed. In the time it took for her to return to the doctor for further treatment, the infection had spread to her kidneys. It took six months before she was finally able to get rid of it.

“A lot can happen in the several days that it takes for the doctor and the patient to determine that the first antibiotic that was given didn’t work,” Mellon said.

More hospitalizations and less successful treatment

More people will also have to be hospitalized for routine infections if the effectiveness of antibiotics continues to decline, Spellberg said.

Oral antibiotics have long been the standard treatment for urinary tract infections, which are diagnosed in one out of three women before the age of 24. But doctors are now seeing E. coli infections of the urinary tract that are resistant to all oral antibiotics, requiring patients to go to the hospital for intravenous antibiotic treatment, Spellberg said. If the antibiotics resistance rate in E. coli becomes high enough, then all patients with urinary tract infections would have to be hospitalized, he said.

And going to the hospital has itself become alarmingly risky. Already, 1.7 million people in the U.S. acquire infections in the hospital each year, resulting in 99,000 deaths, according to the Centers for Disease Control and Prevention.

The increased risks might be particularly acute for those who have a serious disease or who are otherwise especially vulnerable; treatment for cancer patients, people in intensive care, premature babies, and those in need of organ transplants, Spellman said, would all be “dramatically negatively impacted.”

More death

In the pre-antibiotic era, people who got a simple skin infection had a 10 percent chance of dying, and people who contracted pneumonia had a 60 percent chance of dying, Spellberg said.

While he didn’t think mortality rates from infectious diseases would become as high as they were in the days before antibiotics, Spellberg said it was reasonable to think that if we continue down the road we are on today, there will be an increasing number of pathogens for which we have no defense at all.