Infectious Dose

In this episode of Infectious Dose, Heather McSharry talks with Terry Virts—retired NASA astronaut, Air Force colonel, and candidate for Congress in Texas—about what happens when leadership ignores science. Drawing on his experience in aviation, spaceflight, and risk analysis, Terry discusses the real-world consequences of sidelining evidence in public health, climate, and emergency preparedness. The conversation covers COVID-era misinformation, vaccines, measles outbreaks, healthcare access in Texas, and the dismantling of scientific institutions. The episode also explores the parallels between spaceflight safety systems and high-containment biosafety labs—highlighting why science-based leadership isn’t optional when lives are on the line. 🔗 A full transcript PDF is available in the companion blog post at InfectiousDose.com. And Terry's campaign website is: https://www.terryvirts.com/ Follow Terry: @AstroTerry on Insta/Twitter/Bluesky and astro_terry on Threads Follow Heather: @pathogenscribe on Insta/Twitter/Bluesky/Threads

This week in “Seasonal, Not Safe,” we confront the truth about influenza in 2025–2026. It’s not “just the flu.” From the tragic stories of children lost to fast-moving infections, to the science of how influenza spreads, mutates, and turns deadly — this episode explores what’s really happening this season. We break down the rise of Subclade K, current global flu patterns, new U.S. vaccine policy controversies, and what makes the flu virus so evasive. Plus: how antiviral medications work, why vaccination rates are falling, and what’s coming next in the push for a universal flu vaccine.  All citations and updates available in companion blog post at infectiousdose.com

This New Year’s Eve episode isn’t about resolutions — it’s about a reset. In Still Curious: A New Year’s Reset (Without Resolutions), Heather reflects on a difficult year for science, public health, and trust, and makes the case for curiosity as a quieter, steadier way forward. Rather than focusing on optimism or big promises, this episode explores what it means to pause, to stay engaged without burning out, and to carry curiosity into the new year even when certainty feels loud. The episode closes with a gentle midnight mantra for anyone listening alone, early, or in need of calm at the turn of the year. Companion blog post at infectiousdose.com

This month’s Outbreak After Dark is a special holiday episode — and a heavier one. In A Consumption Christmas Carol , we reimagine Dickens’ classic ghost story through the real epidemic that haunted Victorian London: tuberculosis. Long before antibiotics, TB shaped daily life, art, poverty, and policy — romanticized in parlors, devastating in tenements, and deadly across all social classes. Guided by familiar spirits of past, present, and yet to come, we trace how tuberculosis was misunderstood, aestheticized, and ultimately revealed as an airborne infectious disease — one that remains among the world’s deadliest today. This episode blends historical storytelling, medical science, and reflection on why some diseases never truly stay in the past. Because this is a weightier story, we close the episode gathered by the fire for a post-Carol decompression — sharing snacks, drinks, behind-the-scenes thoughts, and space to process the history together. 🕯️ Outbreak After Dark is the after-hours storytelling series of Infectious Dose, where science, history, and a little gothic atmosphere meet.  This episode is an original reimagining inspired by Charles Dickens’ A Christmas Carol.

Show Notes — ACIP Undone: Proof, Policy, and Panic Over a Hepatitis B Vaccine This episode unpacks everything you need to know about hepatitis B and the life-saving vaccine that helps prevent chronic liver disease and liver cancer later in life. From the biology of the virus to the science behind the birth dose, we explore how this vaccine works, why it’s given so early, and what’s at stake now that ideology is overriding evidence in U.S. vaccine policy. We also confront a dangerous shift in public health: the dismantling of expert-driven systems in favor of anti-vaccine rhetoric. The result isn’t just political—it’s personal. And it puts newborns at risk. In this episode: How hepatitis B infects the liver and evades the immune system Why newborns are uniquely vulnerable to chronic infection The history and science behind the universal birth dose What the ACIP overhaul means for public trust and public health Vaccine safety, ingredients, and long-term effectiveness Debunking the most common lies circulating on social media All citations are in the blog post for this episode at infectiousdose.com

A leaked FDA memo sparked headlines claiming the COVID vaccine killed children — but the memo included no evidence, no data, and no scientific analysis. In today’s episode, Heather unpacks what the memo actually said, why experts across the field immediately rejected its conclusions, and how vaccine safety is truly evaluated. She explains the real risks of COVID in kids, from MIS-C to long COVID, and why misinformation from inside federal agencies threatens public trust and puts families at risk. Clear, compassionate, and evidence-driven, this episode gives parents the clarity they deserve. NOTE: All sources are cited in the blog post for this episode at infectiousdose.com

There’s more to your favorite winter rituals than nostalgia. In this episode, we dive into how centuries of winter traditions—across Europe, Asia, Africa, and the Americas—offered accidental protection against infectious diseases. From citrus in stockings to cloves in mulled wine, from kimchi to candlelight, we trace how ancient practices around food, air, warmth, and cleaning helped communities stay healthier in the harshest season. Learn how: Spices like cinnamon, ginger, and clove helped preserve food and reduce pathogens Fires, feasts, and fermentation doubled as primitive infection control Cleaning rituals and seasonal isolation slowed the spread of disease Modern public health can still draw lessons from these old traditions We also address how today’s world—sealed homes, global travel, and misinformation—has changed the game, and why clear science is more important than ever. 🎙️ Plus: a discussion of the recent HHS decision under Robert F. Kennedy Jr. to remove the statement “vaccines do not cause autism” from federal pages—and why this political move contradicts decades of scientific evidence. See the corresponding blog post at infectiousdose.com for all citations.

In this Outbreak After Dark episode, we revisit Thanksgiving’s origin story through the lens of infectious disease. Heather, Sam, and Kate dive into the epidemics that devastated Indigenous nations before the Pilgrims ever arrived, the microbial mismatches between Old World and New, and the narratives that still distort how we talk about “the First Thanksgiving.” It’s a campfire conversation that blends history, science, myth-busting, and respect for the communities whose histories were altered by plague long before the feast. All episode citations and recipes are in the blog post at infectiousdose.com

This week’s episode dives into the roots of the global antimicrobial resistance crisis. How did routine cuts, UTIs, and pneumonias become untreatable? What systems helped superbugs evolve — and why is the problem accelerating worldwide? We explore the science, the policies, the failures, and the future of drug-resistant microbes in A Prescription for Pestilence: The Global Spread of Antimicrobial Resistance. NOTE: All cited references are linked in the blog post for this episode at infectiousdose.com

Rift Valley fever is back — and it’s hitting harder than it has in years. In this episode, we trace the 2025 outbreak from Mauritania to Senegal, explore how the virus hides between rainy seasons, and reveal what scientists have learned from unexpected hotspots in Tanzania. From mosquitoes and livestock to people and policy, this is Rift Valley fever: when the rains bring life and loss. Don't miss today's (Nov 12, 2025) free webinar on RVF: The World Health Organization is hosting a free EPI-WIN webinar at 1pm CET, which is 7pm EST called “Rift Valley Fever and Community Protection: Gaps, Needs and Priorities,” and it brings together experts from WHO, Senegal, and Rwanda.

Headed into holiday travel season? This episode of Infectious Dose is your go-to guide for staying healthy on the road — without panic, shame, or disinfecting your entire row like you're filming a CSI episode. We talk practical prevention for planes, airports, road trips, and cruises, including how to avoid RSV, norovirus, and long COVID, what to pack in your health kit, why snacks matter, and how to travel with kids without losing your mind — or your mask. Smart tips, real science, and relatable chaos, all in one episode. NOTE: PDF Infection Prevention Travel Checklist available for listeners in the blog post at infectiousdose.com

Welcome to Outbreak After Dark, a new monthly ritual within Infectious Dose, where the science stays real but the stories get darker, weirder, and yes—sometimes just plain gross. In this Halloween premiere, Ocularium, Heather is joined by cohosts Kate and Sam, to share true “medical horror” stories about parasites that call the eye home: Loa loa, Onchocerca volvulus, Acanthamoeba, and Thelazia gulosa. 🍂 Grab your themed snacks and cider, settle by the fire, and prepare to see infectious disease in a whole new light—if you can keep your eyes open. 🧠 Learn more and get the recipes at infectiousdose.com

What if you couldn’t wake up—and your mind kept trying to lecture its way out of the dark? In this week’s Month of the Macabre episode, “The Sleep Lecture,” a neurologist begins a talk on encephalitis lethargica—the mysterious “sleepy sickness” that swept the world a century ago—only to discover she’s become part of her own subject. Based on true clinical records and modern research, this immersive narrative blurs the line between dream and science, between consciousness and coma. Listen with the lights low. And maybe don’t fall asleep just yet.   Listener Note: The medical and historical details in this episode are based on real research, but the people and institutions are fictional. Any similarity to real individuals or places is entirely coincidental.

In this special Month of the Macabre episode, Infectious Dose steps into gothic territory with a haunting reimagining of Edgar Allan Poe’s The Raven—rewritten for the age of science denial. The R@VN follows a man who built his fame on rejecting vaccines and mistrusting public health—until a disease he dismissed returns to claim him. As paralysis sets in, his smart-home AI, the Rational Autonomous Virtual Nexus (R@VN), becomes both witness and judge, speaking in clinical tones that sound increasingly like prophecy. What begins as denial ends as digital haunting—a parable for the consequences of rejecting science. It’s fiction… but the danger is real. Listen to the end for a post-credits scene. 🪶 Listen for:– A modern retelling of The Raven with Poe’s original rhythm and rhyme– The intersection of technology, hubris, and health– How polio still haunts us—and why vaccine denial makes it rise again 💉 Related episode: A Plague Returned Note: R@VN is a fictional artificial intelligence system created for storytelling purposes. Any resemblance to actual products, companies, or technologies is purely coincidental. The R@VN is inspired by Edgar Allan Poe’s “The Raven” (1845), now in the public domain.

In 1692, the people of Salem believed the Devil walked among them. But centuries later, scientists and historians would wonder: could the culprit have been something far more earthly—a hallucinogenic fungus lurking in their daily bread? This Month of the Macabre episode of Infectious Dose examines the ergotism theory behind the Salem witch trials, blending science, history, and haunting “found tapes” that may hit too close to home. From convulsive fits and crawling skin to the toxic fungus Claviceps purpurea, we explore the blurred line between infection and imagination—and how fear itself became contagious. Listener note: this episode doesn’t end where you think it will.  See the blog post at infectiousdose.com for more information.

Step into the shoes of a 1970s CDC outbreak detective as a mysterious cluster of fatal pneumonia cases pulls you into the shadows of a crumbling city hotel. In this immersive Month of the Macabre episode, you’ll chase clues through fog-filled ballrooms and forgotten ventilation shafts, racing to stop an invisible killer before it spreads. Along the way, the case, inspired by a real investigation, reveals just how crucial—and fragile—our public health defenses can be. Pair this one with The Andromeda Strain or The Bay and get ready for a suspenseful story of fog, fever, and fieldwork.

Our public health safety net is unraveling. In this episode, we explore why infectious disease surveillance — once our invisible safety net — is quietly vanishing, and what that means for early outbreak detection. Dr. Jim Alwine breaks down common misunderstandings around gain-of-function research and explains how fear-driven narratives like the lab leak theory have warped public perception and policymaking. We also examine how recent regulatory changes are limiting the ability of U.S. scientists to study viruses...and what systems we urgently need to restore if we want to be ready for the next pandemic. Take Action: https://www.defendpublichealth.org/get-involved Further Reading & Resources: TWiV 1121: SARS-CoV-2 Still Didn’t Come from a Lab https://www.microbe.tv/twiv/twiv-1121/  Oversight of Pathogen Research Must Be Carefully Calibrated (J. Virol.) https://journals.asm.org/doi/10.1128/jvi.00176-23 Virology Under the Microscope: A Call for Rational Discourse https://journals.asm.org/doi/10.1128/jvi.00089-23 Improving the Health of America Together – DPH https://www.defendpublichealth.org/resource/improving-health-americans-together-evidence-based-framework-addressing-root-causes Field Research Is Essential to Counter Virological Threats (J. Virol.) https://journals.asm.org/doi/10.1128/jvi.00544-23 🔗 Full article links, summaries, and transcript: infectiousdose.com/jim-alwine

Organizer–sociologist Jon Shaffer, PhD, (Defend Public Health / University of Vermont) joins Heather to talk about turning evidence into local, winnable public-health protections. We dig into why “apolitical” public health backfires, how real teams (not one-off mobilizations) build durable power, and practical, nonpartisan roles for scientists and clinicians—even if you only have an hour a month. Though this moment really deserves more from each of us. In this episode: • Why public health is inherently political—and what it costs to ignore that • Organizing vs. advocacy vs. lobbying (and why teams are the power unit) • What a mini-campaign looks like and how it strengthens a new team • Overcoming fear with relationships, stories, and clear, winnable demands • Why state-level organizing fits local political culture—and actually wins Take action: • Join a digital action today: https://www.defendpublichealth.org/get-involved • Set up a 1:1 with Jon to plug into a state team: jonshaff@gmail.com                                        Disclaimer: Views expressed by guests are their own. (Full blog post + transcript at infectiousdose.com )

West Nile virus is back in the headlines, with new human cases in the U.S. and steady activity in Europe. In this episode of Infectious Dose, Heather tracks the current outbreak season through CDC and ECDC surveillance and state-level reports, explores how the virus cycles between birds and mosquitoes, and examines what happens when you get infected. Most infections are silent, but for a small fraction, West Nile unleashes a devastating attack on the nervous system. With no proven treatments and no human vaccine, prevention remains our best defense—making this one of the most enduring mosquito-borne threats in the U.S. and beyond.

This week, Heather pulls back the curtain on how she figures out what’s true. From gut checks and trusted sources to the brutal training of grad school and the constant practice of science writing, she shares the habits that help her navigate conflicting claims—like the current confusion around COVID vaccine access. You don’t need a PhD to think like a scientist, just the right process.