For more than half a century, scientist Bernard Moss has been commanding the attention of peers interested in prying biological secrets from poxviruses and other microbiological targets. Now he’s commanding the attention of a different audience: House Republicans.
Moss, who will mark his 86th birthday in late July and who goes by Bernie, has worked for more than 55 years in the laboratories of the National Institute of Allergy and Infectious Diseases in Bethesda, Md. Over that time, he has been investigating viruses in relative anonymity — except, that is, among the virological cognoscenti.
But last year, in an interview with Science, Moss said he planned to try to determine why one strain of mpox viruses, known as Clade 1, is so much more virulent than those in a second strain, Clade 2, by taking genes from the former and putting them into the latter. Clade 2 viruses are responsible for the ongoing mpox outbreak first detected in May 2022.
Though the NIAID says Moss never actually conducted the work, his public expression of interest in research that might be seen as a so-called gain-of-function study appears to have been catnip to Republicans on the House Energy and Commerce Committee.
Gain-of-function research is a controversial type of study whereby the risk posed by a pathogen is potentially increased by techniques such as adding or removing genes. Though the concept is poorly understood by the public, in the current political climate the mere term is at times used to evoke images of out-of-control researchers putting scientific glory ahead of the safety of humanity.
In this case it is, in effect, a gong that, once sounded, reverberates with echoes of an unproven yet oft-repeated allegation — that the Covid-19 pandemic was sparked by poorly executed studies on bat coronaviruses at China’s Wuhan Institute of Virology. Some of the coronavirus research at the institute was funded by an NIAID grant, at a time when NIAID was overseen by Anthony Fauci, a popular foil for Republicans.
Plans to do the type of work Moss described in the Science article would need to undergo an internal review to determine if the benefits of having an answer to the question posed outweighed the inherent risks. But a spokesperson for NIAID told STAT in late May that there had been no formal proposal from Moss to do the research and the institution had no plan to proceed with the study.
Fauci, who retired at the end of December, professed to be in the dark about when and how Moss’ plans changed. “I don’t know, to be honest with you,” he said.
The GOP committee members want to know what happened between the time when Moss told Science about his plans and when they asked earlier this year to interview him about the work.
“It seems unlikely that Dr. Moss changed his mind. On the other hand, it is hard to believe the NIAID has apparently overruled one of its most highly respected scientists. These circumstances demand a detailed explanation about what happened with this research project publicized by Dr. Moss,” they wrote in a letter to the Department of Health and Human Services, which oversees the National Institutes of Health.
Moss declined to speak to STAT for this article, and it’s not yet clear if he will sit for the videotaped interview the GOP committee members seek. “HHS remains committed to working in good faith with Congressional oversight efforts,” a spokesperson for the Department of Health and Human Services said via email when STAT asked if NIAID would instruct Moss to take part in the requested interview.
Though Moss’ scientific output is prodigious, his public profile is slight. His Wikipedia entry runs to a scant 450 words. Yet among his peers, Moss is considered a scientific giant. He has published more than 800 scientific articles, which have been cited in other publications nearly 62,600 times.
“There’s no doubt [if] you ask anybody in the field that Bernie Moss is unquestionably one of the best, if not the most important poxvirus scientist in the country, if not the world,” said Fauci, who used to be Moss’ boss at NIAID. Fauci retired as the research institute’s director at the end of 2022 after nearly 40 years in the job. Moss headed the laboratory of viral diseases from 1984 to 2017; he is now chief of the genetic engineering section.
“He’s a very distinguished scientist. Highly, highly regarded and respected in the field. He’s very quiet. Shy,” Fauci told STAT.
Inger Damon, who studied under Moss, also speaks in glowing terms about her former mentor. “He has an amazing brain,” said Damon, a poxvirus expert who was head of the division of high-consequence pathogens and pathology at the Centers for Diseases Control and Prevention until she retired late last summer.
But her description of Moss deviates from Fauci’s on the issue of shyness. “He’s not a shrinking violet,” said Damon, who remains a member of the World Health Organization’s advisory committee for variola virus research — variola is the now-extinct virus that caused smallpox — and the WHO committee tasked with trying to get to the bottom of how the Covid pandemic began.
“In a scientific meeting he will always ask a question of the speaker. It will always be insightful, and it will always open something that people had not necessarily thought of before,” Damon said.
Damon also made a point about the study Moss spoke of undertaking, noting that it’s impossible to know whether work like this would actually make a Clade 2 virus more lethal. Over a decade ago, she and colleagues investigated whether a protein found in Clade 1 viruses but not Clade 2 viruses might explain why the former is so much more lethal than the latter. After getting the necessary ethical permissions, they engineered Clade 2 viruses so that they would generate the protein in question. Its presence made no changes to the lethality of the Clade 2 viruses.
“What it told us is that Clade 1 and Clade 2 … are deeply divergent and have evolved in different ways,” she said.
People who have worked with Moss describe a scientist with a razor-sharp mind, one who created a supportive environment for people who studied under him.
“Some of the best years of my scientific life were spent in his lab,” said Stuart Isaacs, an associate professor of medicine at the Perelman School of Medicine at the University of Pennsylvania, and a co-author in the paper that Damon described. Isaacs said many of the scientists who study poxviruses “can trace our genealogy back to Bernie’s lab.”
“He just had such a diverse group of scientists that were doing all sorts of things, from understanding how genes are turned on and off by the virus, to how genes interact with the immune system, to how the virus spreads in a culture dish, or in an animal,” said Isaacs. “And he became the expert, and he remains the expert on all of those topics.”
Moss’ work also illuminated how vaccinia, the pox virus he has worked on for decades, could be used as the backbone for vaccines. There are now a number of veterinary vaccines that are made using this approach, including one that vaccinates wildlife against rabies.
Rich Condit, a professor emeritus in the University of Florida’s department of molecular genetics and microbiology, is a co-host of the popular podcast “This Week in Virology.” At the end of a nearly two-hour interview with Moss in February 2020, Condit — himself a poxvirologist — opined on what would have happened to the field had Moss followed the path his family had hoped he would take and became a physician.
“Had Bernie done something else, poxvirology — and a lot of other science influenced by poxvirology — would have been completely different,” Condit said. “Bernie’s been the undisputed leader for decades.”
In his childhood, Moss’ eventual career path might have seemed unlikely. The child of immigrants — his mother’s family came to America from Ukraine, his father’s from Romania — he was an indifferent student with mediocre grades, he revealed in a long interview for the National Institutes of Health’s Office of History that was conducted in June 2018.
He loved to read, but not the things his teachers wanted him to focus on. Instead, he’d check out adventure stories from the local library. Still, he scored highly in intellectual testing, and was placed in a program for gifted students, doing his last year of middle school and his first year of high school at the same time in Brooklyn, where he grew up. In his final year of high school, he decided to apply himself to see what happened. He got all As and won a chemistry prize — the first of many strings of As and accolades that would come his way.
He completed undergraduate and medical degrees at New York University, where a stint working in a professor’s laboratory ignited in him a love of research. He thought of switching into a Ph.D. program, but decided to see the medical training through. “I was really on a track,’’ he said. But before he finished his pediatric residency at Boston Children’s Hospital, he knew his future lay not at a bedside, but in the lab. He was given an NIH grant to get a Ph.D., choosing to study at MIT.
In 1966 he joined the U.S. Public Health Service Commissioned Corps — fulfilling a service requirement of the Vietnam draft — and moved to Washington to begin work at the NIH. There, the scientist he went on to work for suggested he study vaccinia, the poxvirus used as the basis for the vaccine that was the tool that led to the successful eradication of smallpox.
Moss, who had wanted to study the functioning of genes, realized that inserting them into vaccinia would allow him to chart the way individual genes functioned. Moss later acknowledged he had gone to “probably the best medical laboratory that I could have for the work that I wanted to do.”
Moss’ work is largely what would be characterized as fundamental biology — figuring out how viruses infect cells, how they co-opt a cell’s internal functions for their own ends, and how a host’s response influences what happens after infection.
“He’s just really creative and really seeing: What is the next question that could be asked? And what’s the right approach to ask that question?” said Damon, who worked in Moss’s lab from 1996 to 1999 while on a postdoctoral infectious diseases fellowship after completing her medical degree at the University of Pennsylvania.
“A lot of what I learned in terms of how I managed a lab when I went to CDC was really reflective of how I saw him manage a lab, in terms of frequent lab meetings where people presented their work, the questions they had. It opened a dialogue where other people within the group, not just the director of the lab … would ask questions,” she said. “It was just a very social and collaborative way of approaching science.”
On the “This Week in Virology” podcast, Moss was asked why he’d never moved on from the NIH. There were opportunities, he acknowledged — but none enticing enough to lure him away.
“For me, I wouldn’t leave unless there was both a pull and a push. And NIAID has been so good to me that I never had a push,” he said.
Retirement may not be on his to-do list either. In the same interview, he noted that when he left the Commissioned Corps after nearly 25 years of service, he met with someone in the NIH’s human resources department who was urging him to choose a retirement plan that would cost him more in deductions while he worked, but pay more in pension benefits on his eventual retirement. He opted for the lower deductions/lower pension benefits plan.
“You have to retire in order to get that advantage,” Moss recalled telling the woman. “And I don’t have a plan to retire.”
Sarah Owermohle contributed reporting.