older people
To Prevent a Stroke, Household Chores and Leisurely Strolls May Help
Posted on by Lawrence Tabak, D.D.S., Ph.D.
As we get older, unfortunately our chances of having a stroke rise. While there’s obviously no way to turn back the clock on our age, fortunately there are ways to lower our risk of a stroke and that includes staying physically active. Take walks, ride a bike, play a favorite sport. According to our current exercise guidelines for American adults, the goal is to get in at least two and a half hours each week of moderate-intensity physical activity as well as two days of muscle-strengthening activity [1].
But a new study, published in the journal JAMA Network Open, shows that reducing the chances of a stroke as we get older doesn’t necessarily require heavy aerobic exercise or a sweat suit [2]. For those who are less mobile or less interested in getting out to exercise, the researchers discovered that just spending time doing light-intensity physical activity—such as tending to household chores—“significantly” protects against stroke.
The study also found you don’t have to dedicate whole afternoons to tidying up around the house to protect your health. It helps to just get up out of your chair for five or 10 minutes at a time throughout the day to straighten up a room, sweep the floor, fold the laundry, step outside to water the garden, or just take a leisurely stroll.
That may sound simple, but consider that the average American adult now spends on average six and a half hours per day just sitting [3]. That comes to nearly two days per week on average, much to the detriment of our health and wellbeing. Indeed, the study found that middle-aged and older people who were sedentary for 13 hours or more hours per day had a 44 percent increased risk of stroke.
These latest findings come from Steven Hooker, San Diego State University, CA, and his colleagues on the NIH-supported Reasons for Geographic and Racial Differences in Stroke (REGARDS) study. Launched in 2003, REGARDS continues to follow over time more than 30,000 Black and white participants aged 45 and older.
Hooker and colleagues wanted to know more about the amount and intensity of exercise required to prevent a stroke. Interestingly, the existing data were relatively weak, in part because prior studies looking at the associations between physical activity and stroke risk relied on self-reported data, which don’t allow for precise measures. What’s more, the relationship between time spent sitting and stroke risk also remained unknown.
To get answers, Hooker and team focused on 7,607 adults enrolled in the REGARDS study. Rather than relying on self-reported physical activity data, team members asked participants to wear a hip-mounted accelerometer—a device that records how fast people move—during waking hours for seven days between May 2009 and January 2013.
The average age of participants was 63. Men and women were represented about equally in the study, while about 70 percent of participants were white and 30 percent were Black.
Over the more than seven years of the study, 286 participants suffered a stroke. The researchers then analyzed all the accelerometer data, including the amount and intensity of their physical activity over the course of a normal week. They then related those data to their risk of having a stroke over the course of the study.
The researchers found, as anticipated, that adults who spent the most time doing moderate-to-vigorous intensity physical activity were less likely to have a stroke than those who spent the least time physically active. But those who spent the most time sitting also were at greater stroke risk, whether they got their weekly exercise in or not.
Those who regularly sat still for longer periods—17 minutes or more at a time—had a 54 percent increase in stroke risk compared to those who more often sat still for less than eight minutes. After adjusting for the time participants spent sitting, those who more often had shorter periods of moderate-to-vigorous activity—less than 10 minutes at a time—still had significantly lower stroke risk. But, once the amount of time spent sitting was taken into account, longer periods of more vigorous activity didn’t make a difference.
While high blood pressure, diabetes, and myriad other factors also contribute to a person’s cumulative risk of stroke, the highlighted paper does bring some good actionable news. For each hour spent doing light-intensity physical activity instead of sitting, a person can reduce his or her stroke risk.
The bad news, of course, is that each extra hour spent sitting per day comes with an increased risk for stroke. This bad news shouldn’t be taken lightly. In the U.S., almost 800,000 people have a stroke each year. That’s one person every 40 seconds with, on average, one death every four minutes. Globally, stroke is the second most common cause of death and third most common cause of disability in people, killing more than 6.5 million each year.
If you’re already meeting the current exercise guidelines for adults, keep up the good work. If not, this paper shows you can still do something to lower your stroke risk. Make a habit throughout the day of getting up out of your chair for a mere five or 10 minutes to straighten up a room, sweep the floor, fold the laundry, step outside to water the garden, or take a leisurely stroll. It could make a big difference to your health as you age.
References:
[1] How much physical activity do adults need? Centers for Disease Control and Prevention. June 2, 2022.
[2] Association of accelerometer-measured sedentary time and physical activity with risk of stroke among US adults. Hooker SP, Diaz KM, Blair SN, Colabianchi N, Hutto B, McDonnell MN, Vena JE, Howard VJ. JAMA Netw Open. 2022 Jun 1;5(6):e2215385.
[3] Trends in sedentary behavior among the US population, 2001-2016. Yang L, Cao C, Kantor ED, Nguyen LH, Zheng X, Park Y, Giovannucci EL, Matthews CE, Colditz GA, Cao Y. JAMA. 2019 Apr 23;321(16):1587-1597.
Links:
Stroke (National Institute of Neurological Disorders and Stroke/NIH)
REGARDS Study (University of Alabama at Birmingham)
NIH Support: National Institute of Neurological Disorders and Stroke; National Institute on Aging
Advancing Access to Hearing Health Care
Posted on by Debara L. Tucci, M.D., M.S., M.B.A., National Institute on Deafness and Other Communication Disorders
By 2050, the World Health Organization estimates that more than 700 million people—or one in every 10 people around the globe—will have disabling hearing loss. In the United States alone, hearing loss affects an estimated 30 million people [1]. Hearing loss can be frustrating, isolating, and even dangerous. It is also associated with dementia, depression, anxiety, reduced mobility, and falls.
Although hearing technologies, such as hearing aids, have improved, not everyone has equal access to these advancements. In fact, though hearing aids and other assistive devices can significantly improve quality of life, only one in four U.S. adults who could benefit from these devices has ever used one. Why? People commonly report encountering economic barriers, such as the high cost of hearing aids and limited access to hearing health care. For some, the reasons are more personal. They may not believe that hearing aids are effective, or they may worry about a perceived negative association with aging. [2].
As the lead federal agency supporting research initiatives to prevent, detect, and treat hearing loss, NIH’s National Institute on Deafness and Other Communication Disorders (NIDCD) conducts and funds research that identifies ways to break down barriers to hearing health care. Decades of NIDCD research informed a recent landmark announcement by the Food and Drug Administration (FDA) creating a new category of over-the-counter (OTC) hearing aids. When the regulation takes effect (expected in 2022), millions of people who have trouble hearing will be able to purchase less expensive hearing aids without a medical exam, prescription, or fitting by an audiologist.
This exciting development has been on the horizon at NIDCD for some time. Back in 2009, NIDCD’s Working Group on Accessible and Affordable Hearing Health Care for Adults with Mild to Moderate Hearing Loss created a blueprint for research priorities.
The working group’s blueprint led to NIDCD funding of more than 60 research projects spanning the landscape of accessible and affordable hearing health care issues. One study showed that people with hearing loss can independently adjust the settings [3] on their hearing devices in response to changing acoustic environments and, when given the ability to control their own hearing aid settings, they were generally more satisfied with the sound of the devices than with the audiologist fit [4].
In 2017, the first randomized, double-blind, placebo-controlled clinical trial comparing an over-the-counter delivery model [5] of hearing aids with traditional fitting by an audiologist also found that hearing aid users in both groups reported similar benefits. A 2019 follow-up study [6] confirmed these results, supporting the viability of a direct-to-consumer service delivery model. A small-business research grant funded by NIDCD led to the first FDA-approved self-fitting hearing aid.
Meanwhile, in 2016, NIDCD co-sponsored a consensus report from the National Academies of Sciences, Engineering, and Medicine (NASEM). The report, Hearing Health Care for Adults: Priorities for Improving Access and Affordability, which was developed by an independent expert panel, recommended that the FDA create and regulate a new category of over-the-counter hearing devices to improve access to affordable hearing aids for adults with perceived mild-to-moderate hearing loss. These devices will not be intended for children or for adults with more severe hearing loss.
In sum, this targeted portfolio of NIDCD-funded research—together with the research blueprint and the NASEM consensus report—provided a critical foundation for the 2021 FDA rule creating the new class of OTC hearing aids. As a result of these research and policy efforts, this FDA rule will make some types of hearing aids less expensive and easier to obtain, potentially improving the health, safety, and well-being of millions of Americans.
Transforming hearing health care for adults in the U.S. remains a public health priority. The NIH applauds the scientists who provided critical evidence leading to the new category of hearing aids, and NIDCD encourages them to redouble their efforts. Gaps in hearing health care access remain to be closed.
The NIDCD actively solicits applications for research projects to fill these gaps and continue identifying barriers to care and ways to improve access. The NIDCD will also continue to help the public understand the importance of hearing health care with resources on its website, such as Hearing: A Gateway to Our World video and the Adult Hearing Health Care webpage.
References:
[1] Hearing loss prevalence in the United States. Lin F, Niparko J, Ferrucci L. Arch Intern Med. 2011 Nov 14;171(20):1851-1852.
[2] Research drives more accessible, affordable hearing care. Tucci DL, King K. The Hearing Journal. May 2020.
[3] A “Goldilocks” approach to hearing aid self-fitting: Ear-canal output and speech intelligibility index. Mackersie C, Boothroyd A, Lithgow, A. Ear and Hearing. Jan 2019.
[4] Self-adjusted amplification parameters produce large between-subject variability and preserve speech intelligibility. Nelson PB, Perry TT, Gregan M, VanTasell, D. Trends in Hearing. 7 Sep 2018.
[5] The effects of service-delivery model and purchase price on hearing-aid outcomes in older adults: A randomized double-blind placebo-controlled clinical trial. Humes LE, Rogers SE, Quigley TM, Main AK, Kinney DL, Herring C. American Journal of Audiology. 1 Mar 2017.
[6] A follow-up clinical trial evaluating the consumer-decides service delivery model. Humes LE, Kinney DL, Main AK, Rogers SE. American Journal of Audiology. 15 Mar 2019.
Links:
National Institute on Deafness and Other Communication Disorders (NIDCD) (NIH)
Funded Research Projects on Accessible and Affordable Hearing Health Care (NIDCD)
Adult Hearing Health Care (NIDCD)
[Note: Acting NIH Director Lawrence Tabak has asked the heads of NIH’s Institutes and Centers (ICs) to contribute occasional guest posts to the blog to highlight some of the interesting science that they support and conduct. This is the ninth in the series of NIH IC guest posts that will run until a new permanent NIH director is in place.]
The Latest on COVID-19 Boosters
Posted on by Dr. Francis Collins
More than 180 million Americans, including more than 80 percent of people over age 65, are fully vaccinated against the SARS-CoV-2 virus responsible for COVID-19. There’s no question that full vaccination is the best way to protect yourself against this devastating virus and reduce your chances of developing severe or long-lasting illness if you do get sick. But, to stay ahead of this terrible virus, important questions do remain. A big one right now is: How soon will booster shots be needed and for whom?
The answers to this question will continue to evolve as more high-quality data become available. But here’s what we know right now for the Pfizer-BioNTech booster. Late last week, Dr. Rochelle Walensky, the Director of the Centers for Disease Control and Prevention (CDC), recommended that:
- Those 65 years and older and residents in long-term care settings should receive a booster shot at least 6 months after being fully vaccinated with the Pfizer-BioNTech vaccine,
- People aged 50–64 years with underlying medical conditions should receive a booster shot at least 6 months after being fully vaccinated with the Pfizer-BioNTech vaccine,
- Individuals aged 18–49 years with underlying medical conditions may receive a booster shot at least 6 months after getting fully vaccinated with their Pfizer-BioNTech vaccine, based on their individual benefits and risks.
- Frontline workers who received the Pfizer-BioNTech vaccine may receive a booster. This group includes anyone age 18 through 64 whose frequent institutional or occupational exposure to SARS-CoV-2 puts them at high risk of COVID-19. [1]
Taken together, these CDC recommendations are in line with those issued two days earlier by the Food and Drug Administration (FDA) [2].
Some of the most-compelling data that was under review came from an Israeli study, published recently in the New England Journal of Medicine, that explored the benefit of booster shots for older people [3]. Israel, with a population of around 9 million, has a national health system and one of the world’s highest COVID-19 vaccination rates. That country’s vaccination campaign, based solely on Pfizer-BioNTech, was organized early in 2021, and so its experience is about three months ahead of ours here in the U.S. These features, plus some of the world’s largest integrated health record databases, have made Israel an important source of early data on how the Pfizer-BioNTech mRNA vaccine can be expected to work in the real world over time.
Earlier this year, Israeli public health officials noted evidence for an increased number of breakthrough infections, some of which were severe. So, at the end of July 2021, Israel approved the administration of third doses, or “boosters,” of the Pfizer-BioNTech vaccine for people ages 60 and up who had received their second dose at least five months before.
To find out how well these booster shots worked to bolster immune protection against COVID-19, researchers looked to more than 1.1 million fully vaccinated people who were at least 60 years old. They compared the rate of confirmed COVID-19 infection and severe illness from the end of July to the end of August among people who’d received a booster at least 12 days earlier with those who hadn’t gotten boosters.
Nearly 13,500 older individuals who’d been fully vaccinated before March 2021, got a breakthrough infection during the two months of study. Importantly, the rate of confirmed infection in the group that got boosters was 10 times lower on average than in the group that didn’t get boosters. The data on severe illness looked even better. Of course, there could be other factors at play that weren’t accounted for in the study, but the findings certainly suggest that a third Pfizer shot is safe and effective for older people.
Though the Israeli studies on booster shots are a little ahead of the international pack, we are starting to see results from the research underway in the U.S. Last week, for example, Johnson & Johnson announced new data in support of boosters to improve and extend immune protection in those who received its single-dose COVID-19 vaccine [4]. For people who received the Moderna mRNA vaccine, the company has already submitted its data to the FDA for booster authorization. A decision is expected soon.
As the critical evidence on boosters continues to emerge, the most important way to avoid another winter surge of COVID-19 is to follow all public health recommendations. Most importantly, that includes getting fully vaccinated if you haven’t already, and encouraging others around you to do the same. If you’re currently eligible for a booster shot, they are available at 80,000 locations across the nation, and can help you stay healthy and well for the coming holiday season.
For others eager to do everything possible to protect themselves, their families, and their communities against this terrible virus—but who are not yet eligible for a booster—sit tight for now. The data on booster shots are still coming in for folks like me who were immunized with the Moderna or Johnson & Johnson vaccines. It’s likely that the FDA and CDC will widen their recommendations in the coming weeks.
In the meantime, the Delta variant is still out there and circulating. That makes it critical to maintain vigilance. Wear a mask in indoor spaces, keep a physical distance from others, and remember to wash your hands frequently. We are all really tired of COVID-19, but patience is still required as we learn more about how best to stay ahead of this virus.
References:
[1] CDC statement on ACIP booster recommendations. Centers for Disease Control and Prevention news release. September 24, 2021
[2] FDA authorizes booster dose of Pfizer-BioNTech COVID-19 vaccine for certain populations. Food and Drug Administration news release. September 22, 2021
[3] Protection of BNT162b2 vaccine booster against Covid-19 in Israel. Bar-On YM, Goldberg Y, Mandel M, Bodenheimer O, Freedman L, Kalkstein N, Mizrahi B, Alroy-Preis S, Ash N, Milo R, Huppert A. N Engl J Med. 2021 Sep 15.
[4] Johnson & Johnson announces real-world evidence and Phase 3 data confirming strong and long-lasting protection of single-shot COVID-19 vaccine in the U.S. Johnson & Johnson. September 21, 2021.
Links:
COVID-19 Research (NIH)
COVID-19 Vaccine Appears Well-Tolerated and Effective in Developing Antibodies in Small Study of Older Adults
Posted on by Dr. Francis Collins
It’s been truly breathtaking to watch the progress being made on a daily basis to develop safe and effective vaccines for SARS-CoV-2, the novel coronavirus that causes COVID-19. Indeed, months sooner than has ever been possible for a newly emerging infection, several promising vaccines are already working their way through Phase 3 studies, the final stage of clinical evaluation. I remain optimistic that we will have one or more vaccines that prove to be safe and effective by January 2021.
But, as encouraging as the early data have been, uncertainty has remained over whether vaccines that appear safe and effective in developing antibodies in younger adults will work as well in older people, too. It’s a critical issue given that older individuals also are at greater risk for severe or life-threatening illness if they do get sick from COVID-19.
So, I’m pleased to highlight some recent findings, published in the New England Journal of Medicine [1], from an early Phase 1 clinical trial that was expanded to include 40 adults over age 55. While we eagerly await the results of ongoing and larger studies, these early data suggest that an innovative COVID-19 vaccine co-developed by NIH’s Vaccine Research Center (VRC), in partnership with Moderna Inc., Cambridge, MA, is both well tolerated and effective in generating a strong immune response when given to adults of any age.
The centerpiece of the vaccine in question, known as mRNA-1273, is a small, non-infectious snippet of messenger RNA (mRNA). When this mRNA is injected into muscle, a person’s own body will begin to make the key viral spike protein. As the immune system detects this spike protein, it spurs the production of antibodies that may help to fend off the novel SARS-CoV-2.
Earlier findings from the NIH-supported phase 1 human clinical trial found mRNA-1273 was safe and effective in generating a vigorous immune response in people ages 18 to 55, when delivered in two injections about a month apart. Based on those findings, a large Phase 3 clinical trial is currently enrolling 30,000 volunteers, with results expected in the next few weeks [2]. But, given that immune response to many other vaccines tends to grow weaker with age, how well would this new COVID-19 vaccine work for older individuals?
To find out, a team at Kaiser Permanente Washington Health Research Institute, Seattle, and Emory University School of Medicine, Atlanta, expanded the initial Phase 1 trial to include 20 healthy volunteers ages 56 to 70 and another 20 healthy volunteers ages 71 and older. Ten volunteers in each of the two older age groups received a lower dose of the vaccine (25 micrograms) in two injections given about a month apart. The other 10 in each age group received a higher dose (100 micrograms), given on the same schedule.
Here’s what they found:
• No volunteers suffered serious adverse events. The most common adverse events were mild-to-moderate in severity and included headache, fatigue, muscle aches, chills and pain at the injection site. Those symptoms occurred most often after the second dose and in individuals receiving the higher dose of 100 micrograms.
• Volunteers showed a rapid production of protective antibodies against the spike protein following immunization. After the second injection, all participants showed a strong immune response, with production of robust binding and neutralizing antibodies against SARS-CoV-2.
• The higher dose of 100 micrograms safely produced a stronger immune response compared to the lower dose, supporting its use in larger clinical studies.
• Most importantly, the immune response observed in these older individuals was comparable to that seen previously in younger adults.
The researchers will continue to follow the volunteer trial participants of all ages for about a year to monitor the vaccine’s longer-term effects. But these findings provided support for continued testing of this promising vaccine in older adults in the ongoing Phase 3 clinical trial.
There are currently four SARS-CoV-2 vaccines in phase 3 clinical trials in the United States (though two are currently on hold). Trials of two more vaccines are expected start in the next month or two.
It is not known whether all of these vaccines will have the same vigorous immune response in older individuals that has been demonstrated for this one. But if more than one of these vaccines turns out to be safe and effective, it will be important to know about the response in various populations, so that distribution to high-risk groups can be planned accordingly.
References:
[1] Safety and immunogenicity of SARS-CoV-2 mRNA-1273 vaccine in older adults. Anderson EJ, Rouphael NG, Widge AT, Jackson LA, Roberts PC, Makhene M, Chappell JD, Denison MR, Stevens LJ, Pruijssers AJ, McDermott AB, Flach B, Lin BC, Doria-Rose NA, O’Dell S, Schmidt SD, Corbett KS, Swanson PA 2nd, Padilla M, Neuzil KM, Bennett H, Leav B, Makowski M, Albert J, Cross K, Edara VV, Floyd K, Suthar MS, Martinez DR, Baric R, Buchanan W, Luke CJ, Phadke VK, Rostad CA, Ledgerwood JE, Graham BS, Beigel JH; mRNA-1273 Study Group. N Engl J Med. 2020 Sep 29.
[2] “Phase 3 clinical trial of investigational vaccine for COVID-19 begins.” National Institutes of Heath. July 27, 2020
Links:
Coronavirus (COVID-19) (NIH)
COVID-19 Prevention Network (National Institute of Allergy and Infectious Diseases/NIH)
Dale and Betty Bumpers Vaccine Research Center (National Institute of Allergy and Infectious Diseases/NIH)
Moderna, Inc. (Cambridge, MA)
Safety and Immunogenicity Study of 2019-nCoV Vaccine (mRNA-1273) for Prophylaxis of SARS-CoV-2 Infection (COVID-19) (ClinicalTrials.gov)
NIH Support: National Institute of Allergy and Infectious Diseases
Largest-Ever Alzheimer’s Gene Study Brings New Answers
Posted on by Dr. Francis Collins
Predicting whether someone will get Alzheimer’s disease (AD) late in life, and how to use that information for prevention, has been an intense focus of biomedical research. The goal of this work is to learn not only about the genes involved in AD, but how they work together and with other complex biological, environmental, and lifestyle factors to drive this devastating neurological disease.
It’s good news to be able to report that an international team of researchers, partly funded by NIH, has made more progress in explaining the genetic component of AD. Their analysis, involving data from more than 35,000 individuals with late-onset AD, has identified variants in five new genes that put people at greater risk of AD [1]. It also points to molecular pathways involved in AD as possible avenues for prevention, and offers further confirmation of 20 other genes that had been implicated previously in AD.
The results of this largest-ever genomic study of AD suggests key roles for genes involved in the processing of beta-amyloid peptides, which form plaques in the brain recognized as an important early indicator of AD. They also offer the first evidence for a genetic link to proteins that bind tau, the protein responsible for telltale tangles in the AD brain that track closely with a person’s cognitive decline.
The new findings are the latest from the International Genomics of Alzheimer’s Project (IGAP) consortium, led by a large, collaborative team including Brian Kunkle and Margaret Pericak-Vance, University of Miami Miller School of Medicine, Miami, FL. The effort, spanning four consortia focused on AD in the United States and Europe, was launched in 2011 with the aim of discovering and mapping all the genes that contribute to AD.
An earlier IGAP study including about 25,500 people with late-onset AD identified 20 common gene variants that influence a person’s risk for developing AD late in life [2]. While that was terrific progress to be sure, the analysis also showed that those gene variants could explain only a third of the genetic component of AD. It was clear more genes with ties to AD were yet to be found.
So, in the study reported in Nature Genetics, the researchers expanded the search. While so-called genome-wide association studies (GWAS) are generally useful in identifying gene variants that turn up often in association with particular diseases or other traits, the ones that arise more rarely require much larger sample sizes to find.
To increase their odds of finding additional variants, the researchers analyzed genomic data for more than 94,000 individuals, including more than 35,000 with a diagnosis of late-onset AD and another 60,000 older people without AD. Their search led them to variants in five additional genes, named IQCK, ACE, ADAM10, ADAMTS1, and WWOX, associated with late-onset AD that hadn’t turned up in the previous study.
Further analysis of those genes supports a view of AD in which groups of genes work together to influence risk and disease progression. In addition to some genes influencing the processing of beta-amyloid peptides and accumulation of tau proteins, others appear to contribute to AD via certain aspects of the immune system and lipid metabolism.
Each of these newly discovered variants contributes only a small amount of increased risk, and therefore probably have limited value in predicting an average person’s risk of developing AD later in life. But they are invaluable when it comes to advancing our understanding of AD’s biological underpinnings and pointing the way to potentially new treatment approaches. For instance, these new data highlight intriguing similarities between early-onset and late-onset AD, suggesting that treatments developed for people with the early-onset form also might prove beneficial for people with the more common late-onset disease.
It’s worth noting that the new findings continue to suggest that the search is not yet over—many more as-yet undiscovered rare variants likely play a role in AD. The search for answers to AD and so many other complex health conditions—assisted through collaborative data sharing efforts such as this one—continues at an accelerating pace.
References:
[1] Genetic meta-analysis of diagnosed Alzheimer’s disease identifies new risk loci and implicates Aβ, tau, immunity and lipid processing. Kunkle BW, Grenier-Boley B, Sims R, Bis JC, et. al. Nat Genet. 2019 Mar;51(3):414-430.
[2] Meta-analysis of 74,046 individuals identifies 11 new susceptibility loci for Alzheimer’s disease. Lambert JC, Ibrahim-Verbaas CA, Harold D, Naj AC, Sims R, Bellenguez C, DeStafano AL, Bis JC, et al. Nat Genet. 2013 Dec;45(12):1452-8.
Links:
Alzheimer’s Disease Genetics Fact Sheet (National Institute on Aging/NIH)
Genome-Wide Association Studies (NIH)
Margaret Pericak-Vance (University of Miami Health System, FL)
NIH Support: National Institute on Aging; National Heart, Lung, and Blood Institute; National Human Genome Research Institute; National Institute of Allergy and Infectious Diseases; Eunice Kennedy Shriver National Institute of Child Health and Human Development; National Institute of Diabetes and Digestive and Kidney Disease; National Institute of Neurological Disorders and Stroke
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