It may seem like an unlikely option, but it was viruses that helped to save Tom Patterson when a superbug threatened his life.

Patterson fell ill during a vacation to Egypt in December 2015, experiencing a racing heart, abdominal pain, fever, nausea and vomiting. He was initially diagnosed with pancreatitis, or inflammation of the pancreas, at a local clinic. But when he didn't improve with standard treatment, he was medevaced to Germany.

That's where doctors discovered he was infected with a multidrug-resistant strain of Acinetobacter baumannii — one of the World Health Organization's so-called "priority pathogens" because of the serious threat they pose to human health.

Once stable, Patterson was airlifted to a hospital at the University of California San Diego's School of Medicine, where he and his wife are both professors.

Dr. Robert Schooley and Dr. Randy Taplitz successfully administered phage therapy to Tom Patterson. (University of California San Diego )

Patterson had been treated with a combination of antibiotics, including colistin, a drug of last resort that can cause kidney damage. But his bacterial isolate had become resistant, and septic shock was ravaging his bloodstream, damaging organs.

He fell into a coma.

With the virulent superbug pushing Patterson closer to death, his wife, infectious-disease specialist Steffanie Strathdee, decided to take a different tack.

Strathdee asked her partner to squeeze her hand if he was ready to fight; she vowed to leave no stone unturned in her search for alternative therapies. Patterson squeezed back his yes.

What she turned to was phage therapy — a treatment that uses bacteriophages, or viruses that infect bacteria.

'We turned viruses into the biggest weapon against a superbug,' says HIV researcher Steffanie Strathdee, Patterson's wife. (University of California San Diego)

Strathdee heard of a less critically ill patient who travelled to Tbilisi, Georgia to undergo the experimental treatment. She herself had learned about bacteriophages as an undergraduate student at the University of Toronto.

Bacteriophages were once used as a treatment in the U.S. and Europe, but when penicillin came to the market in the 1950s, their use was largely abandoned outside of Russia and Poland.

Patterson's medical team agreed to give it a try, sourcing the bacteriophages from the U.S. Navy Medical Center, Texas A&M University and a U.S. biotech firm.

'What did I miss?'

After multiple injections, his infection started to clear.

"[Both] our careers have been [spent] looking at viruses as the enemy because we study HIV," Strathdee said. "But in this case, the enemy of my enemy is my friend. We turned viruses into the biggest weapon against a superbug."

Three days after the phage therapy began, Patterson's coma ended.

"When I first came out of a coma, I said, 'What did I miss?' And she said, 'Well, Donald Trump is the Republican candidate and we cured you with … purified sewage from Texas,'" Patterson recalls.

"And I said, 'I must be hallucinating still.'"

Despite the ick factor, everyone's GI tracts are teeming with both bacteria and bacteriophages. So it makes sense that sewage is a go-to source for researchers seeking raw phages.

Dr. Robert Schooley, chief of infectious diseases at UC San Diego and Patterson's primary physician, said he was largely willing to try phage therapy due to Strathdee's strong advocacy.

"What's different in some ways about this patient was that he was really extremely ill," he said. "At the time, we did this as a last-ditch effort, and decided the risk of giving him the phage intravenously was worth the potential benefit of saving his life that we thought we would otherwise lose."

Memories lit like a Christmas tree

When Patterson first awoke, Strathdee said he lifted his head off the pillow, recognized his daughter and kissed the girl's hand.

Recovering from the coma, however, was a much more gradual process.

At one point, Strathdee showed him a photo of his childhood sweetheart in a beauty contest.

"When she showed me that photograph, it was as if the lights on a Christmas tree, [with just] one string lit up. I was able to recall all kinds of experiences that occurred in that period of my life. It was not like recalling a memory from yesterday. It is like many, small electric shocks in my brain — where bits and pieces were waking up."

Over his nine months in hospital, Patterson lost about 100 pounds of mostly muscle and had to slowly relearn how to swallow and walk. He's now back at work.

'Phages really did something'

Both Schooley and Strathdee say the U.S. Food and Drug Administration facilitated their search for phages, which needed to be matched exactly to the bacteria ravaging Patterson.

"As it turned out, there was really very little evidence of any untoward effects of giving him the phage," Schooley said.

This week marks the 100th anniversary of the discovery of phage therapy. The Paris-based Institut Pasteur celebrated the anniversary with a presentation of Patterson's case.

It also used the occasion to pay tribute to the role of French-Canadian Fé​lix d'Hé​relle in showing how bacteriophages can treat infection.

The now-healthy Patterson was able to join last week's March for Science in San Diego, where he carried an entirely appropriate sign. (Steffanie Strathdee)

Alan Davidson, a microbiologist at the University of Toronto who studies phages, called Patterson's case extremely exciting and impressive.

"There haven't been enough careful trials of this kind of approach," Davidson said. "This [case] seems to be very well-documented and it seems convincing that the phages really did something."

Schooley says he believes phage therapy could be greatly expanded if it were prioritized by government and the pharmaceutical industry.

As for Strathdee, her outlook is even broader.

"Our hope is that we're going to put phage therapy in the spotlight and move the field forward so that can get it to the developing world," she said. "Because the problems of multidrug-resistant bacteria are so just much more rampant in places where there's no real health-care system."