Antibacterial resistance — the ability of bacteria to survive attempts to control or kill them with existing drugs — is widely acknowledged as one of the greatest threats to global public health.
As a World Health Organization official announced a few years ago, “Without urgent, coordinated action by many stakeholders, the world is headed for a post-antibiotic era, in which common infections and minor injuries which have been treatable for decades can once again kill.”
We’re already partially there. In the United States alone, at least 2 million people become infected with drug-resistant bacteria each year, and 23,000 people die as a result of those infections, according to the Centers for Disease Control and Prevention.
Efforts are under way to find new antibiotic drugs, but progress has been slow. Scientists are trying all sorts of approaches, including ones that employ the latest in molecular biology technologies. Earlier this month, for example, a team of Swedish researchers reported how they had used gene sequencing to identify nine different types of Penicillium fungi with a strong potential for producing new antibiotics. (The original antibiotic, penicillin, is derived from such a fungi.)
One of the more intriguing efforts to find new antibiotics, however, has to be the AncientBiotics project. This team of microbiologists, philologists, medicinal chemists, parasitologists, pharmacists, data scientists and medievalists (yes, you read that right) from various universities across the world believes that answers to the antibiotic crisis may be found in medical history.
“To that end, we are compiling a database of medieval medical recipes,” writes AncientBiotics member Erin Connelly, a post-doctoral researcher in medieval studies at the University of Pennsylvania, in a recent article for The Conversation. “By revealing patterns in medieval medical practice, our database could inform future laboratory research into the materials used to treat infection in the past.”
The group has already had one success, as Connelly explains:
In 2015, our team published a pilot study on a 1,000-year old recipe called Bald’s eyesalve from “Bald’s Leechbook,” an Old English medical text. The eyesalve was to be used against a “wen,” which may be translated as a sty, or an infection of the eyelash follicle.
A common cause of modern styes is the bacterium Staphylococcus aureus. Methicillin-resistant Staphylococcus aureus (or MRSA) is resistant to many current antibiotics. Staph and MRSA infections are responsible for a variety of severe and chronic infections, including wound infections, sepsis and pneumonia.
Bald’s eyesalve contains wine, garlic, an Allium species (such as leek or onion) and oxgall. The recipe states that, after the ingredients have been mixed together, they must stand in a brass vessel for nine nights before use.
In our study, this recipe turned out to be a potent antistaphylococcal agent, which repeatedly killed established S. aureus biofilms — a sticky matrix of bacteria adhered to a surface — in an in vitro infection model. It also killed MRSA in mouse chronic wound models.
An important take-away from the Bald’s eyesalve story, Connelly adds, is that practitioners had to follow the recipe precisely, especially the nine-day wait, in order for the remedy to work.
“Are the results of this medieval recipe representative of others that treat infection?” she asks. “Were practitioners selecting and combining materials following some ‘scientific’ methodology for producing biologically active cocktails?”
A cautionary note
These efforts to find new drugs in old treatments should not be viewed as an endorsement of traditional folk medicine, however. Most such remedies were either placebos or, in some cases, palliatives. And certain medieval medicines — like the herb henbane, which was used for pain relief — could be lethal.
Still, Connelly and her AncientBiotics colleagues are optimistic that their efforts to uncover new antibiotics from old remedies will be successful.
“The database could direct us to new recipes to test in the lab in our search for novel antibiotics, as well as inform new research into the antimicrobial agents contained in these ingredients on the molecular level,” she writes. “It could also deepen our understanding of how medieval practitioners ‘designed’ recipes.”
“Our research is in the beginning stages,” she adds, “but it holds exciting potential for the future.”
FMI: You can read Connelly’s article on The Conversation’s website.