An attacking rogue hippo, giant jumping spiders, even a coup in Timbuktu couldn't knock out Tom Patterson, but now he was losing the fight against a microscopic bacteria.
Death seemed inevitable, perhaps hours away, despite heroic efforts to keep him alive.
It was the deadly drug-resistant superbug Acinetobacter baumannii. The infection struck during a holiday trip with his wife to the pyramids in Egypt and had sent his body into toxic shock. His health was deteriorating so rapidly that his insurance company paid to medevac him first to Germany, then home to San Diego.
Weeks passed as he lay in a coma, shedding more than a hundred pounds. Several major organs were on the precipice of collapse, and death seemed inevitable, perhaps hours away despite heroic efforts by a major research university hospital to keep Tom alive.
Tom Patterson in a deep coma on March 14, 2016, the day before phage therapy was initiated.
(Courtesy Steffanie Strathdee)
Then doctors tried something boldly experimental -- injecting him with a cocktail of bacteriophages, tiny viruses that might infect and kill the bacteria ravaging his body.
It worked. Days later Tom's eyes fluttered open for a few brief seconds, signaling that the corner had been turned. Recovery would take more weeks in the hospital and about a year of rehabilitation before life began to resemble anything near normal.
In her new book The Perfect Predator, Tom's wife, Steffanie Strathdee, recounts the personal and scientific ordeal from twin perspectives as not only his spouse but also as a research epidemiologist who has traveled the world to track down diseases.
Part of the reason why Steff wrote the book is that both she and Tom suffered severe PTSD after his illness. She says they also felt it was "part of our mission, to ensure that phage therapy wasn't going to be forgotten for another hundred years."
Tom Patterson and Steffanie Strathdee taking a first breath of fresh air during recovery outside the UCSD hospital.
(Courtesy Steffanie Strathdee)
From Prehistoric Arms Race to Medical Marvel
Bacteriophages, or phages for short, evolved as part of the natural ecosystem. They are viruses that infect bacteria, hijacking their host's cellular mechanisms to reproduce themselves, and in the process destroying the bacteria. The entire cycle plays out in about 20-60 minutes, explains Ben Chan, a phage research scientist at Yale University.
They were first used to treat bacterial infections a century ago. But the development of antibiotics soon eclipsed their use as medicine and a combination of scientific, economic, and political factors relegated them to a dusty corner of science. The emergence of multidrug-resistant bacteria has highlighted the limitations of antibiotics and prompted a search for new approaches, including a revived interest in phages.
Most phages are very picky, seeking out not just a specific type of bacteria, but often a specific strain within a family of bacteria. They also prefer to infect healthy replicating bacteria, not those that are at rest. That's what makes them so intriguing to tap as potential therapy.
Tom's case was one of the first times that phages were successfully infused into the bloodstream of a human.
Phages and bacteria evolved measures and countermeasures to each other in an "arms race" that began near the dawn of life on the planet. It is not that one consciously tries to thwart the other, says Chan, it's that countless variations of each exists in the world and when a phage gains the upper hand and kills off susceptible bacteria, it opens up a space in the ecosystem for similar bacteria that are not vulnerable to the phage to increase in numbers. Then a new phage variant comes along and the cycle repeats.
Robert "Chip" Schooley is head of infectious diseases at the University of California San Diego (UCSD) School of Medicine and a leading expert on treating HIV. He had no background with phages but when Steff, a friend and colleague, approached him in desperation about using them with Tom, he sprang into action to learn all he could, and to create a network of experts who might provide phages capable of killing Acinetobacter.
"There is very little evidence that phage[s] are dangerous," Chip concluded after first reviewing the literature and now after a few years of experience using them. He compares broad-spectrum antibiotics to using a bazooka, where every time you use them, less and less of the "good" bacteria in the body are left. "With a phage cocktail what you're really doing is more of a laser."
Collaborating labs were able to identify two sets of phage cocktails that were sensitive to Tom's particular bacterial infection. And the FDA acted with lightning speed to authorize the experimental treatment.
A bag of a four-phage "cocktail" before being infused into Tom Patterson.
(Courtesy Steffanie Strathdee)
Tom's case was scientifically important because it was one of the first times that phages were successfully infused into the bloodstream of a human. Most prior use of phages involved swallowing them or placing them directly on the area of infection.
The success has since sparked a renewed interest in phages and a reexamination of their possible role in medicine.
Over the two years since Tom awoke from his coma, several other people around the world have been successfully treated with phages as part of their regimen, after antibiotics have failed.
The Future of Phage Therapy
The experience treating Tom prompted UCSD to create the Center for Innovative Phage Applications and Therapeutics (IPATH), with Chip and Steff as co-directors. Previous labs have engaged in basic research on phages, but this is the first clinical center in North America to focus on translating that knowledge into treating patients.
In January, IPATH announced the first phase 2 clinical trial approved by the FDA that will use phages intravenously. The viruses are being developed by AmpliPhi Biosciences, a San Diego-based company that supplied one of the phages used to treat Tom. The new study takes on drug resistant Staph aureus bacteria. Experimental phage therapy treatment using the company's product candidates was recently completed in 21 patients at seven hospitals who had been suffering from serious infections that did not respond to antibiotics. The reported success rate was 84 percent.
The new era of phage research is applying cutting-edge biologic and informatics tools to better understand and reshape the viruses to better attack bacteria, evade resistance, and perhaps broaden their reach a bit within a bacterial family.
Genetic engineering tools are being used to enhance the phages' ability to infect targeted bacteria.
"As we learn more and more about which biological activities are critical and in which clinical settings, there are going to be ways to optimize these activities," says Chip. Sometimes phages may be used alone, other times in combination with antibiotics.
Genetic engineering using tools are being used to enhance the phages' ability to infect targeted bacteria and better counter evolving forms of bacterial resistance in the ongoing "arms race" between the two. It isn't just theory. A patient recently was successfully treated with a genetically modified phage as part of the regimen, and the paper is in press.
In reality, given the trillions of phages in the world and the endless encounters they have had with bacteria over the millennia, it is likely that the exact phages needed to kill off certain bacteria already exist in nature. Using CRISPR to modify a phage is simply a quick way to identify the right phage useful for a given patient and produce it in the necessary quantities, rather than go search for the proverbial phage needle in a sewage haystack, says Chan.
One non-medical reason why using modified phages could be significant is that it creates an intellectual property stake, something that is patentable with a period of exclusive use. Major pharmaceutical companies and venture capitalists have been hesitant to invest in organisms found in nature; but a patentable modification may be enough to draw their interest to phage development and provide the funding for large-scale clinical trials necessary for FDA approval and broader use.
"There are 10 million trillion trillion phages on the planet, 10 to the power of 31. And the fact is that this ongoing evolutionary arms race between bacteria and phage, they've been at it for a millennia," says Steff. "We just need to exploit it."
No human has run a distance of 100 meters faster than Usain Bolt’s lightning streak in 2009. He set this record at age 22. But what will Bolt’s time be when he’s 105?
At the Louisiana Senior Games in November 2021, 105-year-old Julia Hawkins of Baton Rouge became the oldest woman to run 100 meters in an official competition, qualifying her for this year's National Senior Games. Perhaps not surprisingly, she was the only competitor in the race for people 105 and older. In this Leaps.org video, I interview Hawkins about her lifestyle habits over the decades. Then I ask Steven Austad, a pioneer in studying the mechanisms of aging, for his scientific insights into how those aspiring to become super-agers might follow in Hawkins' remarkable footsteps.
Following the Footsteps of a 105-Year-Old SprinterNo human has run a distance of 100 meters faster than Usain Bolt’s lightning streak in 2009. He set this record at age 22. But what will Bolt’s time be when ...
A new virus has emerged and stoked fears of another pandemic: monkeypox. Since May 2022, it has been detected in 29 U.S. states, the District of Columbia, and Puerto Rico among international travelers and their close contacts. On a worldwide scale, as of June 30, there have been 5,323 cases in 52 countries.
The good news: An existing vaccine can go a long way toward preventing a catastrophic outbreak. Because monkeypox is a close relative of smallpox, the same vaccine can be used—and it is about 85 percent effective against the virus, according to the World Health Organization (WHO).
Also on the plus side, monkeypox is less contagious with milder illness than smallpox and, compared to COVID-19, produces more telltale signs. Scientists think that a “ring” vaccination strategy can be used when these signs appear to help with squelching this alarming outbreak.
How it’s transmitted
Monkeypox spreads between people primarily through direct contact with infectious sores, scabs, or bodily fluids. People also can catch it through respiratory secretions during prolonged, face-to-face contact, according to the Centers for Disease Control and Prevention (CDC).
As of June 30, there have been 396 documented monkeypox cases in the U.S., and the CDC has activated its Emergency Operations Center to mobilize additional personnel and resources. The U.S. Department of Health and Human Services is aiming to boost testing capacity and accessibility. No Americans have died from monkeypox during this outbreak but, during the COVID-19 pandemic (February 2020 to date), Africa has documented 12,141 cases and 363 deaths from monkeypox.
Ring vaccination proved effective in curbing the smallpox and Ebola outbreaks. As the monkeypox threat continues to loom, scientists view this as the best vaccine approach.
A person infected with monkeypox typically has symptoms—for instance, fever and chills—in a contagious state, so knowing when to avoid close contact with others makes it easier to curtail than COVID-19.
Advantages of ring vaccination
For this reason, it’s feasible to vaccinate a “ring” of people around the infected individual rather than inoculating large swaths of the population. Ring vaccination proved effective in curbing the smallpox and Ebola outbreaks. As the monkeypox threat continues to loom, scientists view this as the best vaccine approach.
With many infections, “it normally would make sense to everyone to vaccinate more widely,” says Wesley C. Van Voorhis, a professor and director of the Center for Emerging and Re-emerging Infectious Diseases at the University of Washington School of Medicine in Seattle. However, “in this case, ring vaccination may be sufficient to contain the outbreak and also minimize the rare, but potentially serious side effects of the smallpox/monkeypox vaccine.”
There are two licensed smallpox vaccines in the United States: ACAM2000 (live Vaccina virus) and JYNNEOS (live virus non-replicating). The ACAM 2000, Van Voorhis says, is the old smallpox vaccine that, in rare instances, could spread diffusely within the body and cause heart problems, as well as severe rash in people with eczema or serious infection in immunocompromised patients.
To prevent organ damage, the current recommendation would be to use the JYNNEOS vaccine, says Phyllis Kanki, a professor of health sciences in the division of immunology and infectious diseases at the Harvard T.H. Chan School of Public Health. However, according to a report on the CDC’s website, people with immunocompromising conditions could have a higher risk of getting a severe case of monkeypox, despite being vaccinated, and “might be less likely to mount an effective response after any vaccination, including after JYNNEOS.”
In the late 1960s, the ring vaccination strategy became part of the WHO’s mission to globally eradicate smallpox, with the last known natural case described in Somalia in 1977. Ring vaccination can also refer to how a clinical trial is designed, as was the case in 2015, when this approach was used for researching the benefits of an investigational Ebola vaccine in Guinea, Kanki says.
“Since Monkeypox spreads by close contact and we have an effective vaccine, vaccinating high-risk individuals and their contacts may be a good strategy to limit transmission,” she says, adding that privacy is an important ethical principle that comes into play, as people with monkeypox would need to disclose their close contacts so that they could benefit from ring vaccination.
Rapid identification of cases and contacts—along with their cooperation—is essential for ring vaccination to be effective. Although mass vaccination also may work, the risk of infection to most of the population remains low while supply of the JYNNEOS vaccine is limited, says Stanley Deresinski, a clinical professor of medicine in the Infectious Disease Clinic at Stanford University School of Medicine.
Other strategies for preventing transmission
Ideally, the vaccine should be administered within four days of an exposure, but it’s recommended for up to 14 days. The WHO also advocates more widespread vaccination campaigns in the population segment with the most cases so far: men who engage in sex with other men.
The virus appears to be spreading in sexual networks, which differs from what was seen in previously reported outbreaks of monkeypox (outside of Africa), where risk was associated with travel to central or west Africa or various types of contact with individuals or animals from those locales. There is no evidence of transmission by food, but contaminated articles in the environment such as bedding are potential sources of the virus, Deresinski says.
Severe cases of monkeypox can occur, but “transmission of the virus requires close contact,” he says. “There is no evidence of aerosol transmission, as occurs with SARS-CoV-2, although it must be remembered that the smallpox virus, a close relative of monkeypox, was transmitted by aerosol.”
Deresinski points to the fact that in 2003, monkeypox was introduced into the U.S. through imports from Ghana of infected small mammals, such as Gambian giant rats, as pets. They infected prairie dogs, which also were sold as pets and, ultimately, this resulted in 37 confirmed transmissions to humans and 10 probable cases. A CDC investigation identified no cases of human-to-human transmission. Then, in 2021, a traveler flew from Nigeria to Dallas through Atlanta, developing skin lesions several days after arrival. Another CDC investigation yielded 223 contacts, although 85 percent were deemed to be at only minimal risk and the remainder at intermediate risk. No new cases were identified.
How much should we be worried
But how serious of a threat is monkeypox this time around? “Right now, the risk to the general public is very low,” says Scott Roberts, an assistant professor and associate medical director of infection prevention at Yale School of Medicine. “Monkeypox is spread through direct contact with infected skin lesions or through close contact for a prolonged period of time with an infected person. It is much less transmissible than COVID-19.”
The monkeypox incubation period—the time from infection until the onset of symptoms—is typically seven to 14 days but can range from five to 21 days, compared with only three days for the Omicron variant of COVID-19. With such a long incubation, there is a larger window to conduct contact tracing and vaccinate people before symptoms appear, which can prevent infection or lessen the severity.
But symptoms may present atypically or recognition may be delayed. “Ring vaccination works best with 100 percent adherence, and in the absence of a mandate, this is not achievable,” Roberts says.
At the outset of infection, symptoms include fever, chills, and fatigue. Several days later, a rash becomes noticeable, usually beginning on the face and spreading to other parts of the body, he says. The rash starts as flat lesions that raise and develop fluid, similar to manifestations of chickenpox. Once the rash scabs and falls off, a person is no longer contagious.
“It's an uncomfortable infection,” says Van Voorhis, the University of Washington School of Medicine professor. There may be swollen lymph nodes. Sores and rash are often limited to the genitals and areas around the mouth or rectum, suggesting intimate contact as the source of spread.
Symptoms of monkeypox usually last from two to four weeks. The WHO estimated that fatalities range from 3 to 6 percent. Although it’s believed to infect various animal species, including rodents and monkeys in west and central Africa, “the animal reservoir for the virus is unknown,” says Kanki, the Harvard T.H. Chan School of Public Health professor.
Too often, viruses originate in parts of the world that are too poor to grapple with them and may lack the resources to invest in vaccines and treatments. “This disease is endemic in central and west Africa, and it has basically been ignored until it jumped to the north and infected Europeans, Americans, and Canadians,” Van Voorhis says. “We have to do a better job in health care and prevention all over the world. This is the kind of thing that comes back to bite us.”