This 2006 colorized scanning electron micrograph image made available by the Centers for Disease Control and Prevention shows the O157:H7 strain of the E. coli bacteria. On Wednesday, May 26, 2016, U.S. military officials reported the first U.S. human case of bacteria resistant to an antibiotic used as a last resort drug. The 49-year-old woman has recovered from an infection of E. coli resistant to colistin. But officials fear that if the resistance spreads to other bacteria, the country may soon see germs impervious to all antibiotics. (Janice Carr/CDC via AP)
"This is terrifying — I don't think we can overestimate the danger here."
polls here 3602

Health officials are sounding the alarm that a new bacteria resistant to all current antibiotics could leave doctors and hospitals with no way to fight potentially deadly infections.

A Pennsylvania woman was diagnosed this week with a strain of bacteria that researchers said was resistant to their last-resort antibiotic. They fear that if other strains of bacteria evolve to include the same resistance, antibiotics will no longer be effective in fighting infection.

"It is the end of the road for antibiotics unless we act urgently," Dr. Tom Frieden, director of the U.S. Centers for Disease Control and Prevention, said during an appearance in Washington, according to The Associated Press.

"This is terrifying — I don't think we can overestimate the danger here," said Dr. Mark Anderson, an infectious disease specialist with CHI Memorial hospital here in Chattanooga. "We are on the verge of potential catastrophe."

Antibiotics have been available only since the 1940s, when penicillin was introduced. Before that, doctors were often powerless to treat infections.

"There are a lot of things now we hardly even think twice about that killed people on a routine basis," Anderson said. "If someone showed up with one of these, the doctor held their hand, called the priest or minister. That was it."

While doctors and hospitals know how to avoid infections while performing surgeries, they are a common post-surgery occurrence. However, they normally are easily controlled with antibiotics.

But if those antibiotics no longer work, "I face the prospect of not being able to treat [patients] and watching them die," Anderson said. And it isn't just sick people in a hospital who would be at risk. "My family and neighbors and you and I — we're up and about in good health, and if we run into the wrong organism, there is nothing medicine can do for us."

In the Pennsylvania case, the woman had gone to a military clinic and was treated for a urinary tract infection, according to The Associated Press. Initial tests found she was infected with E. coli bacteria, a common variety of germ seen in the gut that often makes its way to the bladder.

But the tests showed this E. coli was resistant to antibiotics commonly used first for such infections. She was successfully treated with another kind of antibiotic.

But while she has recovered, further testing completed in the last week confirmed that the E. coli was carrying a gene for resistance against the drug colistin.

Colistin is an old antibiotic. By the 1970s, doctors had mostly stopped using it because of its harsh side effects. But it was brought back as other antibiotics began losing their effectiveness.

It's used against hard-to-treat bacteria that resist one of the last lines of defense, antibiotics called carbapenems. If those germs pick up the colistin-resistance gene, doctors may be out of treatment options, health officials say.

"This is another piece of a really nasty puzzle that we didn't want to see here," said Dr. Beth Bell, who oversees the CDC's emerging infectious diseases programs.

Researchers blame heavy use of antibiotics by farmers raising domestic livestock and over-prescription by doctors for making the problem worse. Since penicillin was discovered, doctors have realized that when bacteria exposed to antibiotics mutate, some new strains will evolve that are no longer affected by the drug. The greater the exposure, the faster new strains will show up, researchers say.

"We need to stop using antibiotics in animal feed," CHI Memorial's Anderson said. "I grew up in a farming family, but that has to stop. I'm sympathetic to farmers, but it is coming at too high a human cost."

And doctors and hospitals need to greatly reduce the number of prescriptions they write for antibiotics, he added.

"As much as 50 to 60 percent of antibiotics use by doctors and nurse practitioners is incorrect," he said.

One reason for the over-prescribing is that it is often hard for a doctor to tell if a patient has an infection that can be treated with an antibiotic or instead has a virus, which is not affected by antibiotics. New diagnostic tools can scan blood or saliva samples and identify 20-30 strains of bacteria at a time, if they are present, Anderson said. But the challenge is to reduce the cost of the equipment such that it can be afforded by individual doctor's offices or even smaller hospitals.

Anderson is worried that needed changes won't happen fast enough.

"The animal husbandry industry has been reluctant to change. Their bottom line is going to take a hit," he said. "Legislators are reluctant to create laws. Physicians don't want to change. It is hard to change people's practices no matter what field they are in."

But there is no magic cure on the horizon.

"There's promising leads," Anderson said, "but nothing right around the corner. There is no miracle drug at present."

The Associated Press contributed to this story.

Contact staff writer Steve Johnson at 423-757-6673, sjohnson@times, on Twitter @stevejohnsonTFP, or on Facebook,