Infectious Dose

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 epi...

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...

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 rarel...

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 fro...

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 ...

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 fl...

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 i...

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, prese...

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 ...

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 ...

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...

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-busti...

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 Pest...

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.

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...

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 an...

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 rec...

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...

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...