What honeybees can reveal about a neighborhood’s germs — from Queens to Brooklyn to Tokyo

Urban honeybee hives may serve as tiny lighthouses, notifying people of the good and bad germs moving through their neighborhoods, according to a study published Wednesday in the journal Environmental Microbiome. The research team proposes that honeybees could help humans make decisions about the health of their urban surroundings, though the concept would need to mature significantly to do that.

“This methodology uses honeybees as collaborators to help us collect microbial information from the environment,” Dr. Elizabeth Hénaff, a computational biologist and professor at the NYU Tandon School of Engineering who co-led the project, said at a press briefing on Tuesday. “We were looking for systems that already existed — living systems that kind of aggregate and collect information from a broader area.”

Honeybees were solid candidates because they interact with an untold number of places as they forage for food. Each of those settings can harbor a microbiome — a collection of microorganisms or germs that’s unique. Our bodies, the sidewalks outside, the smartphones in our hands and pretty much any non-sterile thing can harbor these invisible ecosystems of bacteria, viruses and fungi.

Part of what they found was a new way to systematically measure the germs that honeybees bring back to artificial hives. They piloted the method in Astoria, Fort Greene and Crown Heights — before successfully replicating the idea in Venice, Sydney, Melbourne and Tokyo. This global tour occurred in 2015 and 2016, but the project remains ongoing in New York.

The findings suggest that foraging honeybees don’t only interact with microbiomes on plants or places where the insects hunt for sweet things. Some bee hives in Tokyo had signs of the bacteria that causes cat scratch fever. This germ, as the name suggests, tends to live in felines but can spread to humans if a cat bites or scratches a person.

“There’s a researcher named Jack Gilbert, who has coined the term microbial cloud,” Hénaff said. “Each human being, each pond, each tree has its own microbial cloud that’s surrounding it. And that occupies a three-dimensional space.”

Hénaff and her colleagues think that bees may encounter these spaces even while the bugs are mostly focused on finding plants and sweets during their foraging missions. That’s how they end up carrying this cornucopia of germs back to a hive.

But Gilbert, a microbial ecologist and pediatrics professor at the University of California San Diego who wasn’t involved with the study, had a mixed view of the project.

He told Gothamist that using bees to surveil the environment is a “fun scientific concept,” but the study is limited when it comes to precisely identifying where those germs came from and what to do about them.

The honeybee hives gave clues to environmental germs that could be beneficial or harmful to humans, plants and the bees themselves. But honeybees typically forage within a 2-mile radius around their hive — an area in NYC that could stretch from downtown Brooklyn to Prospect Park and contain hundreds of thousands of New Yorkers.

Gilbert said, for now, the results could offer some insights into the health of a bee hive, but sussing out the connections to human or plant diseases in the immediate vicinity would require a lot more work.

“You’d need a much longer timeframe….You’d need to capture the human and the plant health data,” Gilbert said. “That’s the basic epidemiology that we all understand from SARS-CoV-2 [coronavirus]. “

How the bee hive study was done

The team worked with urban beekeepers in the survey locations to take honey samples and occasionally swab parts of hives. They also collected debris that the bees discarded outside their homes, including the bodies of their kin who’ve died naturally inside the hives. Bees are known to be neat freaks.

The researchers then used DNA analysis to identify all the random germs that had been brought back to the hives, using a technique known as metagenomics.

One of the project’s inspirations was the mystery of the red honey of Brooklyn, where urban beekeepers in Red Hook noticed their hives produce a rouge version of the delicious foodstuff.

It turned out to be “the maraschino cherry factory that was a mile away — that the bees had gotten into,” said Kevin Slavin, an independent researcher who helped launch the study while working at the MIT Media Lab in Boston. The team also consisted of researchers based at Weill Cornell Medicine, the Parsons School of Design and Cooper Union.

This type of study isn’t new, but it’s advanced in recent years as the price of high-volume genetic analysis has dropped. New Yorkers will recall recent investigations of the microcosmic jungles living on subway poles. Wastewater surveillance, which can detect the coronavirus, polio virus and other harmful pathogens, is basically an examination of the sewage microbiome.

Hénaff, Slavin and Gilbert said knowing more about all of these different microbiomes can help inform ways to improve environmental health — think probiotics but for urbanism.

“There are really interesting strategies that we can use to add microbial diversity back into people’s lives,” Gilbert said. “Using urban farms or teaching outside in parks can provide children with the kind of immune exposure, which would enable them to develop a healthy functioning immune system. And that can have ramifications throughout their life reducing chronic disease.”

In a 2020 study, a research team took dirt from Finnish forests and mixed it into the yards at urban daycares. Diversifying these environmental microbiomes led to an immune system boost for the students. This pattern was mimicked in a study last year of a primary schoolyard in Adelaide, Australia.

“There’s a really growing body of literature that shows that exposure to diverse microbiomes is a key component for positive health outcomes,” Hénaff said.