Hoping to eradicate Lyme disease, doctor baits mice with antibiotics

Kim Lewis believes we might see an end to Lyme disease in the not-too-distant future.

“There's only a handful of diseases that are amenable to eradication,” he said. “I think Lyme is really primed for eradication.”

Lewis, is a professor of biology at Northeastern University and director of that university’s Antimicrobial Discovery Center, which he said “should explain what I do for a living.”

Next summer, Lewis and his colleagues will be releasing antibiotic-laden mouse bait in the woods of Massachusetts, in the hope of halting transmission of the disease at its source.

Lewis has rediscovered a compound, forgotten since the 1950s, that he believes might change the game in how Lyme disease is treated, and perhaps take a major step in getting rid of the disease.

“Mice are the main host and transmitter,” he said. “If you can get rid of the disease in mice, essentially you break the chain of transmission, and that may very well eradicate the disease.”

The syndrome was first identified by researchers from Yale University in the 1970s, found in patients from Lyme and East Lyme. Since then, the disease has spread widely.

Of the 3,320 ticks tested by the state in 2020, 28.8 percent were found to carry Lyme disease.

There were more than 27,500 cases of Lyme disease identified in Connecticut residents in the 11 years between 2009 and 2019, the most recent available data.

There are Lyme disease cases reported every month of the year, according to data from the state Department of Public Health, though there are spikes each year in the summer months, usually in July.

Most of the time, Lyme disease is treated with broad-spectrum antibiotics like doxycycline, Lewis said, “And they work very well.”

But broad-spectrum antibiotics have drawbacks. Their use results in increased antibiotic resistance, which Lewis said was “a huge problem,” and they kill both harmful and helpful bacteria in the body.

So Lewis and his team went digging, literally, for a more specific drug. “We decided that it would be a good idea to define an antibiotic that selectively kills borrelia burgdorferi,” the bacteria that causes Lyme, Lewis said.

They found in soil samples a compound that specifically attacks spirochetes, a type of bacteria like Lyme and syphilis, which “are quite different from other bacteria,” Lewis said.

He found it, hygromycin, which he thought was new but was originally discovered in 1953. It was largely abandoned, he said, because it does not have wide application.

“It's terrifically potent against spirochetes, all spirochetes we tested, including borrelia burgdorferi,” Lewis said.

Lewis’ research is now going on two tracks. They are investigating the use of hygromycin as a treatment in humans, but that’s going to take time. They’re several trials away from seeking FDA approval.

They’re also baiting mouse traps out in the wilds of Massachusetts. Mice are central to the spread of Lyme, considered primary carriers, acting as reservoirs of the disease. The ticks that spread Lyme feed on White-footed mice, so if you can cure the mice, you can maybe cure the disease.

Lewis said he and his colleagues are “gearing up to set out baits next year in the wild,” each bait innoculated with hygromycin. “I actually have a grant from the NIH to try out exactly that proposition.”