The Long Shadow: The Science Behind Long COVID

Four years after the first lockdowns and daily case counts faded from headlines, COVID 19 continues to shape lives in quieter but deeply disruptive ways. For millions of people around the world, the virus did not simply end with a negative test. Instead, it left behind a complex and often invisible condition known as long COVID. This lingering illness challenges how medicine understands recovery, chronic disease, and the long reach of viral infections. In a comprehensive review, Dr. Huda Makhluf of the National University in San Diego, and her colleagues, synthesize what scientists currently know about long COVID and what remains frustratingly uncertain.

Ulcerative colitis, often called UC, is a chronic inflammatory disease of the large intestine that is becoming more common across the world, including among teenagers and young adults. For many patients it begins with subtle warning signs such as abdominal discomfort, diarrhea, fatigue, or traces of blood in the stool. Over time these symptoms can escalate into painful and frightening flare-ups that disrupt education, careers, family life, and emotional well-being. Although modern medicine has become remarkably effective at calming these acute disease episodes, UC remains stubbornly persistent. In most patients the disease returns after periods of apparent recovery, sometimes without any obvious external trigger.

On any given day in the United States, millions of financial decisions are made quietly behind desks and computer screens. A loan officer reviews an application from a small construction company. An algorithm evaluates a mortgage request from a young family. A bank executive signs off on a merger that will reshape the local banking landscape. Each decision may seem technical or routine. Yet together they shape who gets to buy a home, who gets to expand a business, and which communities flourish.

When we imagine research linked to space travel, we often picture rockets, astronauts, and the silence of orbit. Yet some of the most important insights into life beyond Earth happen far from space, in quiet rooms where people lie still for weeks at a time. These are bed rest studies, a unique research model that simulates the effects of microgravity on the human body by asking participants to remain lying down for long periods. While these studies are designed to explore muscles, bones, and metabolism, they also create an unusual social world. What happens to human relationships when movement is restricted, routines are stripped away, and the experience of time changes?

For many couples struggling to conceive, a male infertility diagnosis can feel like a closed door. Roughly half of all infertility cases worldwide stem from male factors, and among these, one of the most frustrating conditions is non-obstructive azoospermia (or NOA for short), a complete absence of sperm caused not by a physical blockage but by a failure of sperm production itself. Until recently, most men with NOA were offered a potentially painful and uncertain procedure called testicular sperm extraction (or TESE). In this surgery, doctors search directly within the testis for a few viable sperm cells that can be used for in vitro fertilization. When successful, the results can be life-changing. When unsuccessful, it is physically invasive, emotionally draining, and often repeated several times in vain.

Hydrogen is often presented as one of the most promising tools we have for cutting carbon emissions, especially in parts of the economy where clean alternatives are limited. Heavy industry, long-distance transport, and chemical manufacturing all need large amounts of energy that cannot easily be supplied by batteries alone. Green hydrogen, produced using renewable electricity, could fill that gap. Governments are investing billions to make this happen, but there is a catch. The technology depends on rare materials that could become a bottleneck just as demand takes off. New research led by Jonathan Ruiz Esquius, and conducted by chemist Sara Riera, at the Carbon Science and Technology Institute in Spain, shows how smarter catalyst design could help remove that barrier.

You may imagine your vasculature as a vast and silent network of tubes, dutifully carrying blood, oxygen, and nutrients to every organ and tissue. These vessels seem purely mechanical, like plumbing hidden behind walls, doing their job quietly and invisibly. Yet modern biology has revealed a far richer and more surprising reality. Blood vessels are lined with living, sensing, responding cells called endothelial cells, and these cells are anything but passive. They listen to chemical signals, respond to stress, regulate traffic, and communicate constantly with the immune system.

Tuberculosis remains one of the world’s oldest and most stubborn infectious diseases, yet the way health systems respond to it is often dogged by modern challenges. Clinics are overcrowded, families must travel long distances, and children with vague or non-specific symptoms are frequently overlooked. For decades, tuberculosis care has been organised around hospitals and specialised facilities, even though the disease itself spreads and takes root in homes and communities. A growing body of research now argues that this mismatch is costing lives, particularly among children. Decentralised models of care, which bring services closer to families and empower community-based health workers, offer a compelling alternative. Recent evidence from multiple settings shows that when tuberculosis care is shifted out of distant clinics and into neighbourhoods and households, access expands with potential to close the current gaps in TB detection, treatment outcomes and prevention that benefit communities and families, including their children.

If you ask someone in the United States whether to reconsider their health insurance plan choices, they may sigh, roll their eyes, and offer a story about navigating a maze of deductibles, networks, and confusing brochures. In practice, most people end up doing the simplest thing possible: they stay in the same plan they are already in. Economists have long noticed this pattern. Even when plans raise their prices or competitors offer better deals, people tend to remain where they are. This raises a fascinating question: do people stay because switching is difficult, or because they genuinely prefer the plan they already have? A new study by the economist Prof. Ariel Pakes of Harvard University, and colleagues Prof. Mark Shepard and Prof. Jack Porter, digs into this puzzle and uncovers some surprising answers. Although the study uses sophisticated mathematical tools, the insights are straightforward and important for anyone interested in how health insurance markets work.

If you were to observe a quiet Dutch pasture, you might not guess that one of the most important climate-resilience workers in the landscape is silently engineering the soil beneath the grass. However, just below your feet, an unassuming creature plays a role in buffering floods, preserving crops during droughts, and quietly maintaining the natural plumbing system of the land. This creature is the humble deep-burrowing earthworm, Lumbricus terrestris (or L. terrestris for short). In recent years, researcher Roos van de Logt of the Louis Bolk Institute, and colleagues, have been uncovering the surprisingly complex story of this earthworm. Their findings suggest that supporting, and in some cases reintroducing, L. terrestris could be a powerful, nature-based tool for helping European grasslands adapt to intensifying climate extremes.