Phages, which are harmless viruses that destroy specific bacteria, are becoming useful tools to protect our food supply.
Every year, one in seven people in America comes down with a foodborne illness, typically caused by a bacterial pathogen, including E.Coli, listeria, salmonella, or campylobacter. That adds up to 48 million people, of which 120,000 are hospitalized and 3000 die, according to the Centers for Disease Control. And the variety of foods that can be contaminated with bacterial pathogens is growing too. In the 20th century, E.Coli and listeria lurked primarily within meat. Now they find their way into lettuce, spinach, and other leafy greens, causing periodic consumer scares and product recalls. Onions are the most recent suspected culprit of a nationwide salmonella outbreak.
Some of these incidents are almost inevitable because of how Mother Nature works, explains Divya Jaroni, associate professor of animal and food sciences at Oklahoma State University. These common foodborne pathogens come from the cattle's intestines when the animals shed them in their manure—and then they get washed into rivers and lakes, especially in heavy rains. When this water is later used to irrigate produce farms, the bugs end up on salad greens. Plus, many small farms do both—herd cattle and grow produce.
"Unfortunately for us, these pathogens are part of the microflora of the cows' intestinal tract," Jaroni says. "Some farmers may have an acre or two of cattle pastures, and an acre of a produce farm nearby, so it's easy for this water to contaminate the crops."
Food producers and packagers fight bacteria by potent chemicals, with chlorine being the go-to disinfectant. Cattle carcasses, for example, are typically washed by chlorine solutions as the animals' intestines are removed. Leafy greens are bathed in water with added chlorine solutions. However, because the same "bath" can be used for multiple veggie batches and chlorine evaporates over time, the later rounds may not kill all of the bacteria, sparing some. The natural and organic producers avoid chlorine, substituting it with lactic acid, a more holistic sanitizer, but even with all these efforts, some pathogens survive, sickening consumers and causing food recalls. As we farm more animals and grow more produce, while also striving to use fewer chemicals and more organic growing methods, it will be harder to control bacteria's spread.
"It took us a long time to convince the FDA phages were safe and efficient alternatives. But we had worked with them to gather all the data they needed, and the FDA was very supportive in the end."
Luckily, bacteria have their own killers. Called bacteriophages, or phages for short, they are viruses that prey on bacteria only. Under the electron microscope, they look like fantasy spaceships, with oblong bodies, spider-like legs and long tails. Much smaller than a bacterium, phages pierce the microbes' cells with their tails, sneak in and begin multiplying inside, eventually bursting the microbes open—and then proceed to infect more of them.
The best part is that these phages are harmless to humans. Moreover, recent research finds that millions of phages dwell on us and in us—in our nose, throat, skin and gut, protecting us from bacterial infections as part of our healthy microbiome. A recent study suggested that we absorb about 30 billion phages into our bodies on a daily basis. Now, ingeniously, they are starting to be deployed as anti-microbial agents in the food industry.
A Maryland-based phage research company called Intralytix is doing just that. Founded by Alexander Sulakvelidze, a microbiologist and epidemiologist who came to the United States from Tbilisi, the capital of Georgia, Intralytix makes and sells five different FDA-approved phage cocktails that work against some of the most notorious food pathogens: ListShield for Listeria, SalmoFresh for Salmonella, ShigaShield for Shigella, another foodborne bug, and EcoShield for E.coli, including the infamous strain that caused the Jack in the Box outbreak in 1993 that killed four children and sickened 732 people across four states. Last year, the FDA granted its approval to yet another Intralytix phage for managing Campylobacter contamination, named CampyShield. "We call it safety by nature," Sulakvelidze says.
Intralytix grows phages inside massive 1500-liter fermenters, feeding them bacterial "fodder."
Photo credit: Living Radiant Photography
Phage preparations are relatively straightforward to make. In nature, phages thrive in any body of water where bacteria live too, including rivers, lakes and bays. "I can dip a bucket into the Chesapeake Bay, and it will be full of all kinds of phages," Sulakvelidze says. "Sewage is another great place to look for specific phages of interest, because it's teeming with all sorts of bacteria—and therefore the viruses that prey on them."
In lab settings, Intralytix grows phages inside massive 1500-liter fermenters, feeding them bacterial "fodder." Once phages multiply enough, they are harvested, dispensed into containers and shipped to food producers who have adopted this disinfecting practice into their preparation process. Typically, it's done by computer-controlled sprayer systems that disperse mist-like phage preparations onto the food.
Unlike chemicals like chlorine or antibiotics, which kill a wide spectrum of bacteria, phages are more specialized, each feeding on specific microbial species. A phage that targets salmonella will not prey on listeria and vice versa. So food producers may sometimes use a combo of different phage preparations. Intralytix is continuously researching and testing new phages. With a contract from the National Institutes of Health, Intralytix is expanding its automated high-throughput robot that tests which phages work best against which bacteria, speeding up the development of the new phage cocktails.
Phages have other "talents." In her recent study, Jaroni found that phages have the ability to destroy bacterial biofilms—colonies of microorganisms that tend to grow on surfaces of the food processing equipment, surrounding themselves with protective coating that even very harsh chemicals can't crack.
"Phages are very clever," Jaroni says. "They produce enzymes that target the biofilms, and once they break through, they can reach the bacteria."
Convincing the FDA that phages were safe to use on food products was no easy feat, Sulakvelidze says. In his home country of Georgia, phages have been used as antimicrobial remedies for over a century, but the FDA was leery of using viruses as food safety agents. "It took us a long time to convince the FDA phages were safe and efficient alternatives," Sulakvelidze says. "But we had worked with them to gather all the data they needed, and the FDA was very supportive in the end."
The agency had granted Intralytix its first approval in 2006, and over the past 10 years, the company's sales increased by over 15-fold. "We currently sell to about 40 companies and are in discussions with several other large food producers," Sulakvelidze says. One indicator that the industry now understands and appreciates the science of phages was that his company was ranked as Top Food Safety Provider in 2021 by Food and Beverage Technology Review, he adds. Notably, phage sprays are kosher, halal and organic-certified.
Intralytix's phage cocktails to safeguard food from bacteria are approved for consumers in addition to food producers, but currently the company sells to food producers only. Selling retail requires different packaging like easy-to-use spray bottles and different marketing that would inform people about phages' antimicrobial qualities. But ultimately, giving people the ability to remove pathogens from their food with probiotic phage sprays is the goal, Sulakvelidze says.
It's not the company's only goal. Now Intralytix is going a step further, investigating phages' probiotic and therapeutic abilities. Because phages are highly specialized in the bacteria they target, they can be used to treat infections caused by specific pathogens while leaving the beneficial species of our microbiome intact. In an ongoing clinical trial with Mount Sinai, Intralytix is now investigating a potential phage treatment against a certain type of E. coli for patients with Crohn's disease, and is about to start another clinical trial for treating bacterial dysentery.
"Now that we have proved that phages are safe and effective against foodborne bacteria," Sulakvelidze says, "we are going to demonstrate their potential in therapeutic applications."
This article was first published by Leaps.org on October 27, 2021.
A patient getting examined at health startup Forward.
What if going to the doctor's office could be … nice?
If you didn't have to wait for your appointment, but were ushered right in; if your medical data was all collated and easily searchable on an iPhone app; if a remote scribe took notes while you spoke with your doctor so you could make eye contact with them; if your doctor didn't seem horribly rushed.
Would you go to the doctor to get help staying healthy, rather than just to stop being sick?
Would that change the way you thought about your health? Would you go to the doctor to get help staying healthy, rather than just to stop being sick? And would that, in the long run, be much better for you?
Those are the animating questions for Forward, a healthcare startup devoted to preventive care. Led by founder Adrian Aoun, formerly of Google/Sidewalk labs, Forward opened its first office in San Francisco in 2016 and has since expanded to Los Angeles, Orange County, New York, and Washington, D.C., with a San Diego location opening soon.
It's been described as the "Apple Store of doctor's offices," which in some ways is a reaction to Forward's vibe: Patients have described the offices as having blonde wood, minimalist design, sparkling water on tap — and lots of high-tech gadgets, like the full-body scanner that replaces the standard scale and stethoscope.
The interior of a Forward office.
(Courtesy Forward)
The more crucial difference, though, is its model of care. Forward doesn't take insurance. Instead, patients, or "members," pay a flat $149 per month, along the lines of a subscription service like Netflix or a gym membership. That fee covers visits, messaging with medical staff through the Forward app, the use of a wearable (like a Fitbit or a sleep tracker) if the physician recommends it, plus any bloodwork or diagnostic tests run in the on-site labs. (The company declined to disclose how many people have signed up for memberships.)
Predictability is Forward's other significant, distinguishing feature: No surprise co-pays, or extra charges showing up on a billing statement months later. Everything is wrapped up in the $149 membership fee, unless the physician recommends visiting an outside specialist.
That caveat isn't a small one. It's important to note that Forward is in no way meant to replace standard health insurance. The service is strictly focused on preventive care, so it wouldn't be much use in case of an emergency; it's meant to help people, as far as is possible, avoid that emergency at all.
Ani Okkasian's family recently went through such an emergency. Her 62-year-old father, an active and seemingly healthy man living with diabetes, had been feeling unwell for a while, but struggled to receive constructive follow-up or tests from his doctor. It finally emerged that his liver was severely damaged, and he suffered a stroke — the risk of which can be elevated by liver disease. He seemed to deteriorate completely within mere weeks, Okkasian said, and in January he passed away.
"He was someone who'd go to the doctor regularly and listen to what they said and follow it," Okkasian said. "I shouldn't have had to bury my father at 62. I still believe to my core that his death could have been avoided if the primary care was adequate."
"I could tell that the people who designed [Forward] had lost someone to the legacy system; it was so streamlined and so much clearer."
Okkasian began researching, looking for a better alternative, and discovered Forward. Founder Aoun lost his grandfather to a heart attack; his brother's heart attack at age 31 was the impetus to start Forward.
"I could tell that that was the genesis," Okkasian said. "Having just lost someone, and having had to deal with different aspects of the healthcare industry — how complicated and convoluted that all is — I could tell that the people who designed [Forward] had lost someone to the legacy system; it was so streamlined and so much clearer."
So Who Is Forward For?
The Affordable Care Act mandates that evidence-based preventive care must be covered by insurers without any cost to the patient. Today, 30 million Americans are still living without health insurance; but for most of the population, cost shouldn't prevent access to standard, preventive care, says Benjamin Sommers, a physician and professor at the Harvard T.H. Chan School of Public Health who has studied the effect of the ACA on preventive care access.
For Okkasian and her family, it wasn't a lack of access to primary care that was at issue; it was the quality of that primary care. In 2019, that's probably true for a lot of people.
"How come all other industries have been disturbed except the medical industry?" Okkasian asked. "It's disturbing the most people. We're so advanced in so many ways, but when it comes to the healthcare system, we're not prioritizing the wellness of a person."
Is Forward the answer? Well, probably not for everyone. Its office are only in a handful of cities, and there are limits to how scalable it would be; it's unavoidable that the $149 per month charge restricts access for a lot of people. Those who have insurance through their employer might have a flexible spending account (FSA) that would cover some or all of the membership fee, and Forward has said that 15 percent of their early members came from underserved communities and were offered free plans; but for many others, that's just an unworkable extra cost.
Sommers also sounded a dubious note about a maximalist attitude toward data collection.
"Even though some patients may think that 'more is always better' — more testing, more screening, etc. — this isn't true," he said. "Some types of cancer screening, ovarian cancer screening for instance, are actually harmful or of no benefit, because studies have shown that they don't improve survival or health outcomes, but can lead to unnecessary testing, pain, false positives, anxiety, and other side effects.
"It's really great for people who are in good health, looking to make it better."
"I'm generally skeptical of efforts to charge people more to get 'extra testing' that isn't currently supported by the medical evidence," he added.
But relatively healthy people who want to take a more active approach to their health — or people who have frequent testing needs, like those using the HIV-prevention drug PrEP, and want to avoid co-pays — might benefit from the on-demand, low-friction experience that Forward offers.
"It's really great for people who are in good health, looking to make it better," Okkasian said. "Your experience is simplified to a point where you feel empowered, not scared."
