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Public Health Policies Have Prevented Hundreds of Millions of Coronavirus Infections

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Touchless carryout
Credit: Stock photo/Juanmonino

The alarming spread of coronavirus disease 2019 (COVID-19) last winter presented a profound threat to nations around the world. Many government leaders responded by shutting down all non-essential activities, implementing policies that public health officials were hopeful could slow the highly infectious SARS-CoV-2, the novel coronavirus that causes COVID-19.

But the shutdown has come at a heavy cost for the U.S. and global economies. It’s also taken a heavy personal toll on many of us, disrupting our daily routines—getting children off to school, commuting to the office or lab, getting together with friends and family, meeting face to face to plan projects, eating out, going to the gym—and causing lots of uncertainty and frustration.

As difficult as the shutdowns have been, new research shows that without these public health measures, things would have been much, much worse. According to a study published recently in Nature [1], the implementation of containment and mitigation strategies across the globe prevented or delayed about 530 million coronavirus infections across six countries—China, South Korea, Iran, Italy, France, and the United States. Take a moment to absorb that number—530 million. Right now, there are 8.8 million cases documented across the globe.

Estimates of the benefits of anti-contagion policies have drawn from epidemiological models that simulate the spread of COVID-19 in various ways, depending on assumptions built into each model. But models are sophisticated ways of guessing. Back when decisions about staying at home had to be made, no one knew for sure if, or how well, such approaches to limit physical contact would work. What’s more, the only real historical precedent was the 1918 Spanish flu pandemic in a very different, much-less interconnected world.

That made it essential to evaluate the pros and cons of these public health strategies within a society. As many people have rightfully asked: are the health benefits really worth the pain?

Recognizing a pressing need to answer this question, an international team of scientists dropped everything that they were doing to find out. Led by Solomon Hsiang, director of the University of California, Berkeley’s Global Policy Laboratory and Chancellor’s Professor at the Goldman School of Public Policy, a research group of 15 researchers from China, France, South Korea, New Zealand, Singapore, and the United States evaluated 1,717 policies implemented in all six countries between January 2020, when the virus began its global rise, and April 6, 2020.

The team relied on econometric methods that use statistics and math to uncover meaningful patterns hiding in mountains of data. As the name implies, these techniques are used routinely by economists to understand, in a before-and-after way, how certain events affect economic growth.

In this look-back study, scientists compare observations before and after an event they couldn’t control, such as a natural disaster or disease outbreak. In the case of COVID-19, these researchers compared public health datasets in multiple localities (e.g., states or cities) within each of the six countries before and several weeks after lockdowns. For each data sample from a given locality, the time period right before a policy deployment was the experimental “control” for the same locality several weeks after it received one or more shutdown policy “treatments.”

Hsiang and his colleagues measured the effects of all the different policies put into place at local, regional, and national levels. These included travel restrictions, business and school closures, shelter-in-place orders, and other actions that didn’t involve any type of medical treatment for COVID-19.

Because SARS-CoV-2 is a new virus, the researchers knew that early in the pandemic, everyone was susceptible, and the outbreak would grow exponentially. The scientists could then use a statistical method designed to estimate how the daily growth rate of infections changed over time within a location after different combinations of large-scale policies were put into place.

The result? Early in the pandemic, coronavirus infection rates grew 38 percent each day, on average, across the six countries: translating to a two-day doubling time. Applying all policies at once slowed the daily COVID-19 infection rate by 31 percentage points! Policies having the clearest benefit were business closures and lockdowns, whereas travel restrictions and bans on social gatherings had mixed results. Without more data, the analysis can’t specify why, but the way different countries enacted those policies might be one reason.

As we continue to try to understand and thwart this new virus and its damage to so many aspects of our personal and professional lives, these new findings add context, comfort, and guidance about the present circumstances. They tell us that individual sacrifices from staying home and canceled events contributed collectively to a huge, positive impact on the world.

Now, as various communities start cautiously to open up, we should continue to practice social distancing, mask wearing, and handwashing. This is not the time to say that the risk has passed. We are all tired of the virus and its consequences for our personal lives, but the virus doesn’t care. It’s still out there. Stay safe, everyone!

Reference:

[1] The effect of large-scale anti-contagion policies on the COVID-19 pandemic. Hsiang S, Allen D, Annan-Phan S, et al. Nature. 2020 June 8 [published online ahead of print].

Links:

Coronavirus (NIH)

Global Policy Lab: Effect of Anti-Contagion Policies (University of California, Berkeley)

Video: How much have policies to slow COVID-19 worked? (UC Berkeley)

Hsiang Lab (UC Berkeley)

Global Policy Lab Rallies for COVID-19 Research,” COVID-19 News, Goldman School of Public Policy, June 5, 2020.


Battling Malaria at the Atomic Level

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Cryo-EM Image of P. falciparum Protein
Credit: Columbia University Irving Medical Center, New York

Tropical medicine has its share of wily microbes. Among the most clever is the mosquito-borne protozoan Plasmodium falciparum, which is the cause of the most common—and most lethal—form of malaria. For decades, doctors have used antimalarial drugs against P. falciparum. But just when malaria appeared to be well on its way to eradication, this parasitic protozoan mutated in ways that has enabled it to resist frontline antimalarial drugs. This resistance is a major reason that malaria, one of the world’s oldest diseases, still claims the lives of about 400,000 people each year [1].

This is a situation with which I have personal experience. Thirty years ago before traveling to Nigeria, I followed directions and took chloroquine to prevent malaria. But the resistance to the drug was already widespread, and I came down with malaria anyway. Fortunately, the parasite that a mosquito delivered to me was sensitive to another drug called Fansidar, which acts through another mechanism. I was pretty sick for a few days, but recovered without lasting consequences.

While new drugs are being developed to thwart P. falciparum, some researchers are busy developing tools to predict what mutations are likely to occur next in the parasite’s genome. And that’s what is so exciting about the image above. It presents the unprecedented, 3D atomic-resolution structure of a protein made by P. falciparum that’s been a major source of its resistance: the chloroquine-resistance transporter protein, or PfCRT.

In this cropped density map, you see part of the protein’s biochemical structure. The colorized area displays the long, winding chain of amino acids within the protein as helices in shades of green, blue and gold. These helices enclose a central cavity essential for the function of the protein, whose electrostatic properties are shown here as negative (red), positive (blue), and neutral (white). All this structural information was captured using cryo-electron microscopy (cryo-EM). The technique involves flash-freezing molecules in liquid nitrogen and bombarding them with electrons to capture their images with a special camera.

This groundbreaking work, published recently in Nature, comes from an NIH-supported multidisciplinary research team, led by David Fidock, Matthias Quick, and Filippo Mancia, Columbia University Irving Medical Center, New York [2]. It marks a major feat for structural biology, because PfCRT is on the small side for standard cryo-EM and, as Mancia discovered, the protein is almost featureless.

These two strikes made Mancia and colleagues wonder at first whether they would swing and miss at their attempt to image the protein. With the help of coauthor Anthony Kossiakoff, a researcher at the University of Chicago, the team complexed PfCRT to a bulkier antibody fragment. That doubled the size of their subject, and the fragment helped to draw out PfCRT’s hidden features. One year and a lot of hard work later, they got their homerun.

PfCRT is a transport protein embedded in the surface membrane of what passes for the gut of P. falciparum. Because the gene encoding it is highly mutable, the PfCRT protein modified its structure many years ago, enabling it to pump out and render ineffective several drugs in a major class of antimalarials called 4-aminoquinolines. That includes chloroquine.

Now, with the atomic structure in hand, researchers can map the locations of existing mutations and study how they work. This information will also allow them to model which regions of the protein to be on the lookout for the next adaptive mutations. The hope is this work will help to prolong the effectiveness of today’s antimalarial drugs.

For example, the drug piperaquine, a 4-aminoquinoline agent, is now used in combination with another antimalarial. The combination has proved quite effective. But recent reports show that P. falciparum has acquired resistance to piperaquine, driven by mutations in PfCRT that are spreading rapidly across Southeast Asia [3].

Interestingly, the researchers say they have already pinpointed single mutations that could confer piperaquine resistance to parasites from South America. They’ve also located where new mutations are likely to occur to compromise the drug’s action in Africa, where most malarial infections and deaths occur. So, this atomic structure is already being put to good use.

Researchers also hope that this model will allow drug designers to make structural adjustments to old, less effective malarial drugs and perhaps restore them to their former potency. Perhaps this could even be done by modifying chloroquine, introduced in the 1940s as the first effective antimalarial. It was used worldwide but was largely shelved a few decades later due to resistance—as I experienced three decades ago.

Malaria remains a constant health threat for millions of people living in subtropical areas of the world. Wouldn’t it be great to restore chloroquine to the status of a frontline antimalarial? The drug is inexpensive, taken orally, and safe. Through the power of science, its return is no longer out of the question.

References:

[1] World malaria report 2019. World Health Organization, December 4, 2019

[2] Structure and drug resistance of the Plasmodium falciparum transporter PfCRT. Kim J, Tan YZ, Wicht KJ, Erramilli SK, Dhingra SK, Okombo J, Vendome J, Hagenah LM, Giacometti SI, Warren AL, Nosol K, Roepe PD, Potter CS, Carragher B, Kossiakoff AA, Quick M, Fidock DA, Mancia F. Nature. 2019 Dec;576(7786):315-320.

[3] Determinants of dihydroartemisinin-piperaquine treatment failure in Plasmodium falciparum malaria in Cambodia, Thailand, and Vietnam: a prospective clinical, pharmacological, and genetic study. van der Pluijm RW, Imwong M, Chau NH, Hoa NT, et. al. Lancet Infect Dis. 2019 Sep;19(9):952-961.

Links:

Malaria (National Institute of Allergy and Infectious Diseases/NIH)

Fidock Lab (Columbia University Irving Medical Center, New York)

Video: David Fidock on antimalarial drug resistance (BioMedCentral/YouTube)

Kossiakoff Lab (University of Chicago)

Mancia Lab (Columbia University Irving Medical Center)

Matthias Quick (Columbia University Irving Medical Center)

NIH Support: National Institute of Allergy and Infectious Diseases; National Institute of General Medical Sciences; National Heart, Lung, and Blood Institute


Celebrating 2019 Biomedical Breakthroughs

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Science 2019 Biomedical Breakthroughs and a Breakdown

Happy New Year! As we say goodbye to the Teens, let’s take a look back at 2019 and some of the groundbreaking scientific discoveries that closed out this remarkable decade.

Each December, the reporters and editors at the journal Science select their breakthrough of the year, and the choice for 2019 is nothing less than spectacular: An international network of radio astronomers published the first image of a black hole, the long-theorized cosmic singularity where gravity is so strong that even light cannot escape [1]. This one resides in a galaxy 53 million light-years from Earth! (A light-year equals about 6 trillion miles.)

Though the competition was certainly stiff in 2019, the biomedical sciences were well represented among Science’s “runner-up” breakthroughs. They include three breakthroughs that have received NIH support. Let’s take a look at them:

In a first, drug treats most cases of cystic fibrosis: Last October, two international research teams reported the results from phase 3 clinical trials of the triple drug therapy Trikafta to treat cystic fibrosis (CF). Their data showed Trikafta effectively compensates for the effects of a mutation carried by about 90 percent of people born with CF. Upon reviewing these impressive data, the Food and Drug Administration (FDA) approved Trikafta, developed by Vertex Pharmaceuticals.

The approval of Trikafta was a wonderful day for me personally, having co-led the team that isolated the CF gene 30 years ago. A few years later, I wrote a song called “Dare to Dream” imagining that wonderful day when “the story of CF is history.” Though we’ve still got more work to do, we’re getting a lot closer to making that dream come true. Indeed, with the approval of Trikafta, most people with CF have for the first time ever a real chance at managing this genetic disease as a chronic condition over the course of their lives. That’s a tremendous accomplishment considering that few with CF lived beyond their teens as recently as the 1980s.

Such progress has been made possible by decades of work involving a vast number of researchers, many funded by NIH, as well as by more than two decades of visionary and collaborative efforts between the Cystic Fibrosis Foundation and Aurora Biosciences (now, Vertex) that built upon that fundamental knowledge of the responsible gene and its protein product. Not only did this innovative approach serve to accelerate the development of therapies for CF, it established a model that may inform efforts to develop therapies for other rare genetic diseases.

Hope for Ebola patients, at last: It was just six years ago that news of a major Ebola outbreak in West Africa sounded a global health emergency of the highest order. Ebola virus disease was then recognized as an untreatable, rapidly fatal illness for the majority of those who contracted it. Though international control efforts ultimately contained the spread of the virus in West Africa within about two years, over 28,600 cases had been confirmed leading to more than 11,000 deaths—marking the largest known Ebola outbreak in human history. Most recently, another major outbreak continues to wreak havoc in northeastern Democratic Republic of Congo (DRC), where violent civil unrest is greatly challenging public health control efforts.

As troubling as this news remains, 2019 brought a needed breakthrough for the millions of people living in areas susceptible to Ebola outbreaks. A randomized clinical trial in the DRC evaluated four different drugs for treating acutely infected individuals, including an antibody against the virus called mAb114, and a cocktail of anti-Ebola antibodies referred to as REGN-EB3. The trial’s preliminary data showed that about 70 percent of the patients who received either mAb114 or the REGN-EB3 antibody cocktail survived, compared with about half of those given either of the other two medicines.

So compelling were these preliminary results that the trial, co-sponsored by NIH’s National Institute of Allergy and Infectious Diseases (NIAID) and the DRC’s National Institute for Biomedical Research, was halted last August. The results were also promptly made public to help save lives and stem the latest outbreak. All Ebola patients in the DRC treatment centers now are treated with one or the other of these two options. The trial results were recently published.

The NIH-developed mAb114 antibody and the REGN-EB3 cocktail are the first therapeutics to be shown in a scientifically rigorous study to be effective at treating Ebola. This work also demonstrates that ethically sound clinical research can be conducted under difficult conditions in the midst of a disease outbreak. In fact, the halted study was named Pamoja Tulinde Maisha (PALM), which means “together save lives” in Kiswahili.

To top off the life-saving progress in 2019, the FDA just approved the first vaccine for Ebola. Called Ervebo (earlier rVSV-ZEBOV), this single-dose injectable vaccine is a non-infectious version of an animal virus that has been genetically engineered to carry a segment of a gene from the Zaire species of the Ebola virus—the virus responsible for the current DRC outbreak and the West Africa outbreak. Because the vaccine does not contain the whole Zaire virus, it can’t cause Ebola. Results from a large study in Guinea conducted by the WHO indicated that the vaccine offered substantial protection against Ebola virus disease. Ervebo, produced by Merck, has already been given to over 259,000 individuals as part of the response to the DRC outbreak. The NIH has supported numerous clinical trials of the vaccine, including an ongoing study in West Africa.

Microbes combat malnourishment: Researchers discovered a few years ago that abnormal microbial communities, or microbiomes, in the intestine appear to contribute to childhood malnutrition. An NIH-supported research team followed up on this lead with a study of kids in Bangladesh, and it published last July its groundbreaking finding: that foods formulated to repair the “gut microbiome” helped malnourished kids rebuild their health. The researchers were able to identify a network of 15 bacterial species that consistently interact in the gut microbiomes of Bangladeshi children. In this month-long study, this bacterial network helped the researchers characterize a child’s microbiome and/or its relative state of repair.

But a month isn’t long enough to determine how the new foods would help children grow and recover. The researchers are conducting a similar study that is much longer and larger. Globally, malnutrition affects an estimated 238 million children under the age 5, stunting their normal growth, compromising their health, and limiting their mental development. The hope is that these new foods and others adapted for use around the world soon will help many more kids grow up to be healthy adults.

Measles Resurgent: The staff at Science also listed their less-encouraging 2019 Breakdowns of the Year, and unfortunately the biomedical sciences made the cut with the return of measles in the U.S. Prior to 1963, when the measles vaccine was developed, 3 to 4 million Americans were sickened by measles each year. Each year about 500 children would die from measles, and many more would suffer lifelong complications. As more people were vaccinated, the incidence of measles plummeted. By the year 2000, the disease was even declared eliminated from the U.S.

But, as more parents have chosen not to vaccinate their children, driven by the now debunked claim that vaccines are connected to autism, measles has made a very preventable comeback. Last October, the Centers for Disease Control and Prevention (CDC) reported an estimated 1,250 measles cases in the United States at that point in 2019, surpassing the total number of cases reported annually in each of the past 25 years.

The good news is those numbers can be reduced if more people get the vaccine, which has been shown repeatedly in many large and rigorous studies to be safe and effective. The CDC recommends that children should receive their first dose by 12 to 15 months of age and a second dose between the ages of 4 and 6. Older people who’ve been vaccinated or have had the measles previously should consider being re-vaccinated, especially if they live in places with low vaccination rates or will be traveling to countries where measles are endemic.

Despite this public health breakdown, 2019 closed out a memorable decade of scientific discovery. The Twenties will build on discoveries made during the Teens and bring us even closer to an era of precision medicine to improve the lives of millions of Americans. So, onward to 2020—and happy New Year!

Reference:

[1] 2019 Breakthrough of the Year. Science, December 19, 2019.

NIH Support: These breakthroughs represent the culmination of years of research involving many investigators and the support of multiple NIH institutes.


Exploring the Universality of Human Song

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Analysis of Music-Internationally

It’s often said that music is a universal language. But is it really universal? Some argue that humans are just too culturally complex and their music is far too varied to expect any foundational similarity. Yet some NIH-funded researchers recently decided to take on the challenge, using the tools of computational social science to analyze recordings of human songs and other types of data gathered from more than 300 societies around the globe.

In a study published in the journal Science [1], the researchers conclude that music is indeed universal. Their analyses showed that all of the cultures studied used song in four similar behavioral contexts: dance, love, healing, and infant care. What’s more, no matter where in the world one goes, songs used in each of those ways were found to share certain musical features, including tone, pitch, and rhythm.

As exciting as the new findings may be for those who love music (like me), the implications may extend far beyond music itself. The work may help to shed new light on the complexities of the human brain, as well as inform efforts to enhance the role of music in improving human health. The healing power of music is a major focus of the NIH-supported Sound Health Initiative.

Samuel Mehr, a researcher at Harvard University, Cambridge, MA, led this latest study, funded in part by an NIH Director’s Early Independence Award. His multi-disciplinary team included anthropologists Manvir Singh, Harvard, and Luke Glowacki, Penn State University, State College; computational linguist Timothy O’Donnell, McGill University, Montreal, Canada; and political scientists Dean Knox, Princeton University, Princeton, NJ, and Christopher Lucas, Washington University, St. Louis.

In work published last year [2], Mehr’s team found that untrained listeners in 60 countries could on average discern the human behavior associated with culturally unfamiliar musical forms. These behaviors included dancing, soothing a baby, seeking to heal illness, or expressing love to another person.

In the latest study, the team took these initial insights and applied them more broadly to the universality of music. They started with the basic question: Do all human societies make music?

To find the answer, the team accessed Yale University’s Human Relations Area Files, an internationally recognized database for cultural anthropologists. This rich resource contains high-quality data for 319 mostly tribal societies across the planet, allowing the researchers to search archival information for mentions of music. Their search pulled up music tags for 309 societies. Digging deeper in other historical records not in the database, the team confirmed that the remaining six societies did indeed make music.

The researchers propose that these 319 societies provide a representative cross section of humanity. They thus conclude that it is statistically probable that music is in fact found in all human societies.

What exactly is so universal about music? To begin answering this complex question, the researchers tapped into more than a century of musicology to build a vast, multi-faceted database that they call the Natural History of Song (NHS).

Drawing from the NHS database, the researchers focused on nearly 5,000 vocally performed songs from 60 carefully selected human societies on all continents. By statistically analyzing those musical descriptions, they found that the behaviors associated with songs vary along three dimensions, which the researchers refer to as formality, arousal, and religiosity.

When the researchers mapped the four types of songs from their earlier study—love, dance, lullaby, and healing—onto these dimensions, they found that songs used in similar behavioral contexts around the world clustered together. For instance, across human societies, dance songs tend to appear in more formal contexts with large numbers of people. They also tend to be upbeat and energetic and don’t usually appear as part of religious ceremonies. In contrast, love songs tend to be more informal and less energetic.

Interestingly, the team also replicated its previous study in a citizen-science experiment with nearly 30,000 participants living in over 100 countries worldwide. They found again that listeners could tell what kinds of songs they were listening to, even when those songs came from faraway places. They went on to show that certain acoustic features of songs, like tempo, melody, and pitch, help to predict a song’s primary behavioral function across societies.

In many musical styles, melodies are composed of a fixed set of distinct tones organized around a tonal center (sometimes called the “tonic,” it’s the “do” in “do-re-mi”). For instance, the researchers explain, the tonal center of “Row Your Boat” is found in each “row” as well as the last “merrily,” and the final “dream.”

Their analyses show that songs with such basic tonal melodies are widespread and perhaps even universal. This suggests that tonality could be a means to delve even deeper into the natural history of world music and other associated behaviors, such as play, mourning, and fighting.

While some aspects of music may be universal, others are quite diverse. That’s particularly true within societies, where people may express different psychological states in song to capture their views of their culture. In fact, Mehr’s team found that the musical variation within a typical society is six times greater for that reason than the musical diversity across societies.

Following up on this work, Mehr’s team is now recruiting families with young infants for a study to understand how they respond to their varied collection of songs. Meanwhile, through the Sound Health Initiative, other research teams around the country are exploring many other ways in which listening to and creating music may influence and improve our health. As a scientist and amateur musician, I couldn’t be more excited to take part in this exceptional time of discovery at the intersection of health, neuroscience, and music.

References:

[1] Universality and diversity in human song. Mehr SA, Singh M, Knox D, Ketter DM, Pickens-Jones D, Atwood S, Lucas C, Jacoby N, Egner AA, Hopkins EJ, Howard RM, Hartshorne JK, Jennings MV, Simson J, Bainbridge CM, Pinker S, O’Donnell TJ, Krasnow MM, Glowacki L. Science. 2019 Nov 22;366(6468).

[2] Form and function in human song. Mehr SA, Singh M, York H, Glowacki L, Krasnow MM. Curr Biol. 2018 Feb 5;28(3):356-368.e5.

Links:

Sound Health Initiative (NIH)

Video: Music and the Mind—A Q & A with Renée Fleming & Francis Collins (YouTube)

The Music Lab (Harvard University, Cambridge, MA)

Samuel Mehr (Harvard)

NIH Director’s Early Independence Award (Common Fund)

NIH Support: Common Fund


Charting Research Careers in Global Health

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That’s me at the 67th annual meeting of the American Society of Tropical Medicine and Hygiene (ASTMH). I took part in a townhall-style conversation with ASTMH President Chandy John (far middle, blue shirt). We discussed global health and NIH’s efforts to build career opportunities for trainees abroad. Afterwards, folks in the audience gathered with follow-up questions and to ask for selfies with me, which is always fun. The session was held on November 22, 2019 at the Gaylord National Resort and Convention Center, Washington, D.C. Credit: Karen Goraleski.

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