Infectious Dose

Ebola nears 4,000 confirmed cases in the Democratic Republic of the Congo, New World screwworm continues circulating in Texas, and the U.S. cyclosporiasis outbreak is expanding.

In this Outbreak Watch, we look at what has changed and what the evidence actually tells us, including why there’s currently no evidence that mutation explains the severity of the Ebola outbreak and wh...

A summer morning at the lake is about swimming, skipping stones, dragonflies, and family memories, but it's also the perfect opportunity to explore one of nature's most fascinating invisible ecosystems.

In this episode, we're diving beneath the surface of freshwater lakes to discover how microbes respond to changing environmental conditions throughout t...

Medicine. Contraband. Comfort.

Step inside a hidden 1920s speakeasy where the jazz is live, the whiskey is illegal, and one of the most surprising chapters in medical history unfolds.

During Prohibition, physicians could legally prescribe medicinal whiskey for illnesses ranging from pneumonia and influenza to pain and "nervous exhaustion." At the same time, bootleggers, pharmacists, lawmakers, and patients were all navigating a con...

For much of history, entering a hospital could be one of the most dangerous decisions a person could make. Patients survived injuries and operations only to die from infections acquired in the very places meant to heal them.

In this final episode of our Turning Points in Infectious Disease series, we explore the revolution that transformed hospitals from centers of disease transmission into institutions designed to prevent infectio...

In this edition of Outbreak Watch, we provide a current briefing on the major outbreaks unfolding now, including Ebola in the Democratic Republic of the Congo and Uganda, New World screwworm in the United States, and the rapidly growing U.S. cyclosporiasis outbreak. Along the way, we answer the questions listeners are asking most.

We also examine several emerging signals, including ...

For most of human history, epidemics were something people endured—not prevented. Smallpox alone killed hundreds of millions of people, leaving survivors scarred, blinded, or forever changed. But hidden within that devastation was a remarkable observation: those who survived rarely became sick again.

In this episode, we explore the centuries-lon...

For much of history, disease claimed more soldiers than combat.

In this episode of Infectious Dose, we trace the evolution of military preventive medicine—from the Revolutionary War to the present day—and explore how armies came to view infectious disease as an operational threat rather than an unavoidable consequence of war.

We'll follow the story through George Washington's smallpox inoculation campaign, Florence Nigh...

In the mid‑20th century, ranchers across the southern United States watched livestock being literally eaten alive by a flesh‑eating parasite: New World screwworm. This episode tells the story of how an entomologist’s “absurd” idea helped eradicate screwworm from North America, and why that victory is suddenly back in the spotlight as new cases appear in Texas in 2026. We fo...

June's Summer Rain series wraps up with a tribute to Gulf Coast mosquitoes.

In this episode of Outbreak After Dark, Heather and Kate explore the anatomy of a mosquito bite—from the moment a female mosquito detects carbon dioxide to the itch that keeps you awake long after she's gone.

Topics include:

• How mosquitoes find humans...

Outbreak Watch returns with updates on three unfolding biological events and the systems responding to them.

This week:

• The Bundibugyo Ebola outbreak in the Democratic Republic of the Congo becomes the largest on record as contact tracing, clean water access, and response operations face growing challenges...

You can smell rain before it arrives.

The air changes. The wind shifts. And somehow, before the first drop falls, you already know a storm is coming.

In this immersive episode of Infectious Dose, we explore the science behind that experience. We'll follow a summer storm from distant rain clouds to the microbes ...

In this episode of Infectious Dose, Heather explores one of the strangest allergic conditions modern medicine has ever identified: a syndrome in which a tick bite can trigger an allergy to mammalian meat weeks, months, or even years later.

Why do symptoms often appear in the middle of the night instead of immediately after a meal? How did a cancer drug help scientists solve the myst...

In this episode of Infectious Dose, Heather explores the infectious disease risks that follow hurricanes, tropical storms, and flooding events. Learn how severe weather changes exposure pathways for pathogens already present in our environment and why recovery can create unique health challenges long after the rain stops.

Topics include:

• Floodwater and wou...

Introducing Outbreak Watch by Infectious Dose. When major outbreaks evolve quickly, Heather will occasionally release these extra episodes featuring timely updates and systems-focused analysis.

In this first Outbreak Watch episode, we examine the rapidly escalating Bundibugyo Ebola outbreak in eastern DRC and Uganda alongside the continuing Andes hantavirus cluster linked to the MV Hondius cruise ship.

We break down the latest WHO ...

A nurse in Louisiana receives an HIV diagnosis that doesn’t make sense.

No clear exposure. No obvious source. And eventually, investigators begin to suspect something far more disturbing.

In this episode of Outbreak After Dark, Heather and Kate explore the real case that brought forensic virology into the courtroom for the first time. Through genetic sequencing and phylogenetic analysis, scientists traced the relationships be...

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
• Wh...

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 w...

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...

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 enema...