A new Ebola outbreak is unfolding in Central Africa — this time caused by Bundibugyo ebolavirus. As cases rise in the Democratic Republic of the Congo and Uganda, fear and misinformation are spreading too. In this episode, we break down: What Ebola actually is How Ebola spreads — and how it doesn’t Why healthcare workers and caregivers are at highest risk What happens inside the body during Ebola infection Why Ebola outbreaks amplify through strained systems The latest updates on the 2026 Bundib...
May 20, 2026•44 min•Season 2Ep. 20
Last week, the central question surrounding the MV Hondius outbreak was whether Andes virus was spreading person-to-person at all. This week, the evidence shifted. In Part 2 of Hantavirus on the High Seas, we revisit the major questions from last week’s episode and examine what new genomic data, case timelines, and public-health guidance now suggest about the outbreak. We break down what changed, what remains uncertain, and why the public conversation around “airborne” spread, “prolonged close c...
May 13, 2026•36 min•Season 2Ep. 19
A hantavirus outbreak linked to a cruise ship has triggered fear, speculation, and growing debate online about whether the virus could be spreading person-to-person. But what do we actually know right now? In this episode, Heather breaks down the current hantavirus cruise cluster through the lens of science communication and uncertainty. Rather than focusing only on the facts of the outbreak, this episode explores a bigger question: What does trustworthy, imperfect outbreak communication sound l...
May 06, 2026•18 min•Season 2Ep. 18
Imagine getting sick in the 1700s—before microbes were discovered, before antibiotics, and before infection had a clear cause. In this Outbreak After Dark episode, we explore the strange, unsettling, and sometimes surprisingly insightful treatments used to fight disease in the pre-germ theory era. From bloodletting and mercury to tobacco smoke enemas and malariotherapy, these practices reflect a time when medicine was working without seeing the real enemy. Along the way, we also uncover the rare...
Apr 29, 2026•43 min•Season 2Ep. 17
There’s a virus you probably already have. Epstein–Barr virus infects nearly 95% of adults worldwide. For many, it shows up once—fatigue, a sore throat, maybe a diagnosis of mononucleosis—and then disappears. But EBV doesn’t disappear. It stays, establishing lifelong infection inside B cells—the very cells responsible for immune memory. Most of the time, the immune system keeps it under control. But EBV is not passive. It shifts between latency and reactivation, adapts to immune pressure, and in...
Apr 22, 2026•21 min•Season 2Ep. 16
Murine typhus is a flea-borne bacterial infection that continues to circulate in parts of the United States, particularly in urban and suburban environments. But it’s often missed—because its symptoms are nonspecific, its rash may be subtle or absent, and it doesn’t fit the diagnostic patterns clinicians expect. In this episode, we explore: How murine typhus is transmitted (and why fleas matter more than you think) The role of urban ecology, including opossums, rodents, and flea vectors What hap...
Apr 15, 2026•25 min•Season 2Ep. 15
One year in, Heather steps back to reflect on what this podcast has become—and what changed along the way. What started as a focus on clear, accurate science grew into something more layered: an exploration of how trust, systems, and lived experience shape the way people understand infectious disease. It also opened the door to creative storytelling, immersive formats, and conversations that challenged her own assumptions. This episode includes a few short clips from the past year—moments that c...
Apr 08, 2026•20 min•Season 2Ep. 14
You’re about to step inside a BSL-4 lab. Not a tour. Not an explanation. An experience. You’ll move through clearance. Suit up. Connect to air. And cross the threshold into one of the most controlled environments in the world. Inside, the work is methodical. Quiet. Precise. And everything you think you know about these labs… starts to shift. Put your headphones on. And step inside. More information and resources can be found at infectiousdose.com....
Apr 01, 2026•35 min•Season 2Ep. 13
The plague doctor: a symbol of fear, medicine, and mystery. But were they really the heroes we imagine—or something more complicated? In this Outbreak After Dark episode, we explore the real history behind the iconic beaked mask. From medieval theories of “bad air” to the rise of quarantine systems and early public health policy, we follow the evolution of plague response—and the role of the doctors at its center. Along the way, we unpack: What plague doctors actually did (and didn’t do) Why the...
Mar 25, 2026•39 min•Season 2Ep. 12
What if the biggest misunderstandings about vaccine safety aren’t just about the science—but about how the system communicates it? In this updated guided tour of the Vaccine Safety Series, Heather maps the episodes that break down how vaccines are tested, monitored, and evaluated—and where communication and institutional failures have contributed to confusion and mistrust. This episode is designed to help you navigate the series—whether you’re new, revisiting key topics, or looking for the right...
Mar 18, 2026•28 min•Season 2Ep. 11
When we talk about misinformation in public health, we usually imagine social media, conspiracy theories, or individuals misunderstanding science. But what if some of the most influential misinformation starts somewhere else? In this episode of Infectious Dose , Heather speaks with biomedical researcher Dr. Mark Ungrin about how scientific ideas move through institutional systems and why correcting errors can be surprisingly difficult once they become embedded in policy. They discuss: Why “human...
Mar 11, 2026•1 hr 1 min•Season 2Ep. 10
Mpox isn’t just a headline from 2022. In this episode, we explore what scientists have learned about mpox since the global outbreak — from how the virus moves through the body to why its lesions can be so painful. We break down the biology of orthopoxviruses, the surprising role of human immune enzymes in shaping viral evolution, and the emergence of a new lineage known as clade Ib that researchers are watching closely. We also look at the bigger picture: wildlife reservoirs, genomic surveillanc...
Mar 04, 2026•50 min•Season 2Ep. 9
What if attraction isn’t entirely yours? In this Outbreak After Dark episode, Heather, Kate, and Sam gather around the campfire to explore the parasites, fungi, and viruses that manipulate behavior in the name of survival. We’re talking: Toxoplasma gondii, the parasite that dampens rodents’ fear of cats The lancet liver fluke, which turns ants into grazing bait Ophiocordyceps, the real-life “zombie ant” fungus Baculoviruses that liquefy caterpillars from the treetops Hairworms that drive cricket...
Feb 25, 2026•49 min•Season 2Ep. 8
Nipah virus scares virologists, and for good reason. It infects endothelial cells and neurons. It can cause fatal encephalitis. It spreads from bats to humans, and sometimes between people. So why does it keep burning out? In this episode of Infectious Dose , we examine: Henipavirus biology and receptor usage (ephrin-B2/B3) Why neurotropism drives severity Why outbreaks are small but deadly Why R₀ remains low What would actually have to change for Nipah to go pandemic Why spillover keeps recurri...
Feb 18, 2026•35 min•Season 2Ep. 7
Syphilis is back—and it never really left. In this episode, we break down how a curable, preventable infection is resurging to cause a public health crisis across the U.S., and globally, especially among pregnant people and newborns. We unpack the science behind Treponema pallidum , the public health failures driving the crisis, and why trust in health systems is still broken—from Tuskegee to today. Plus: what you need to know about testing, treatment, and why a shot of penicillin makes all the ...
Feb 11, 2026•19 min•Season 2Ep. 6
This short, standalone episode is a statement of ethics. It explains why this podcast will not remain silent in the face of state violence, the dismantling of public health, and the normalization of harm against vulnerable people. It clarifies the ethical boundaries that guide the work behind Infectious Dose : that science is for everyone, but cruelty, authoritarianism, and the protection of abuse are not neutral positions. This episode is not a scientific explainer and not an invitation to deba...
Feb 06, 2026•3 min
RSV is one of the most common respiratory viruses — and a leading cause of hospitalization in young children worldwide. In this solo episode, I explain what RSV is, how it spreads, and what illness typically looks like in babies, children, and adults. We cover when RSV can be managed at home, how to recognize breathing-related red flags, when to go to the ER or call an ambulance, and what supportive care actually helps. The episode also looks at the current RSV landscape, including rising cases ...
Feb 04, 2026•23 min•Season 2Ep. 5
Spiders inspire some of our deepest fears—but are they actually as dangerous as we think? In this Outbreak After Dark episode, Heather, Sam, and Kate dig into the real science behind spiders, venom, and so-called “spider bites,” separating evidence from exaggeration. Along the way, they unpack persistent myths, medical misattribution, and why spiders loom so large in outbreak lore—despite rarely being the culprit. Creepy? Yes. Deadly? Usually not. Welcome to Outbreak After Dark. Editor's Note: W...
Jan 28, 2026•42 min•Season 2Ep. 4
What are biological weapons—and what are they not? In this episode, Heather is joined by bio-risk consultant and biodefense researcher Conor Browne for a grounded, reality-based conversation about biological weapons, biodefense, and why public discourse around these topics so often goes wrong. Together, they unpack what actually defines a biological weapon, why intent and delivery matter, and how real historical programs differ from the conspiratorial narratives dominating social media and polit...
Jan 21, 2026•1 hr 17 min•Season 2Ep. 3
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...
Jan 14, 2026•34 min•Season 2Ep. 2
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 vac...
Jan 07, 2026•25 min•Season 2Ep. 1
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 cl...
Dec 31, 2025•14 min•Season 1Ep. 44
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,...
Dec 24, 2025•28 min•Season 1Ep. 43
This episode was updated in March 2026 to explicitly frame the hepatitis B birth dose controversy through a systems-level lens — examining how evidence-based vaccine policy can be destabilized when institutional safeguards are removed, and why recognizing those failures is essential to restoring public trust. 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 t...
Dec 17, 2025•29 min•Season 1Ep. 42
This episode was updated in March 2026 to clarify that the analysis presented already reflects the systems-level framework used throughout this vaccine safety series — examining what the claim gets right, where institutional safeguards failed, and what evidence would actually be required to support the claims being made. 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, Heat...
Dec 10, 2025•20 min•Season 1Ep. 41
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 pres...
Dec 03, 2025•20 min•Season 1Ep. 40
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 ...
Nov 26, 2025•21 min•Season 1Ep. 39
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 infectiousdos...
Nov 19, 2025•30 min•Season 1Ep. 38
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...
Nov 12, 2025•27 min•Season 1Ep. 37
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 relatabl...
Nov 05, 2025•30 min•Season 1Ep. 36
