Infectious Dose

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

Plus: a Galveston mosquito disaster and an unexpectedly heated discussion about the plural of proboscis.

Recipes for Night Hum, Wheal & Fizz, Grilled Proboscides, and Afterbite are available in the accompanying blog post at infectiousdose.com

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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.

• The Andes hantavirus outbreak linked to the MV Hondius cruise ship is behaving as expected, providing an important lesson in what successful containment looks like.

• New World screwworm detections in the United States highlight ongoing debates about surveillance, preparedness, and the challenges of responding to an emerging threat when critical systems must be rebuilt.

In this episode, we explore visibility, uncertainty, and the operational realities that shape outbreak response long before most people hear about it.

For weekly outbreak updates, subscribe to the free Infectious Dose newsletter, Field Notes, at infectiousdose.com

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 living beneath our feet, uncovering the roles of petrichor, geosmin, and the remarkable biology behind one of nature's most beloved scents.

Along the way, we'll explore why humans are so sensitive to the smell of rain, how storms become tied to memory, and why a single breath of cool air before a summer downpour can transport us years into the past.

Part science story. Part sensory journey. Part summer rain. 

Experience audio of a real summer storm from Heather's patio

Part of our June series: Stories of Summer Rain.

Citations in companion blog post at Infectiousdose.com

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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 mystery? Where does the alpha-gal molecule come from, and why do ticks seem uniquely capable of triggering this unusual immune response?

Join us as we follow the trail from the woods to the dinner table and unravel the science behind alpha-gal syndrome.

In this episode:

• What alpha-gal syndrome is and how it develops

Part of our June series, Stories of Summer Rain, this episode explores how warm, wet environments shape the ecosystems around us—and how those ecosystems can unexpectedly shape our health.

Referenced resources and scientific citations are available at InfectiousDose.com.

Subscribe to Field Notes, the free Infectious Dose newsletter, for weekly Outbreak Watch updates and additional resources.

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 wound infections

Plus: A free downloadable Infectious Disease Hurricane Preparedness Guide with checklists, safety tips, emergency reference formulas, and a personal medical information worksheet. Download in companion blog post at Infectious Dose.

The storm isn't always the biggest health risk. Sometimes it's the week after.

Subscribe to the free Infectious Dose newsletter, Field Notes, here. 

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 numbers, why Ebola transmission is accelerating through conflict-affected mining corridors, what new genomic and geospatial analyses reveal about the outbreak’s spread, and why public-health responders are struggling to contain it amid violence and instability.

We also discuss the newest hantavirus cases emerging internationally weeks after passengers returned home, why the slow appearance of additional cases is expected for Andes virus, and how this cluster has already affected global biocontainment logistics.

Finally, we look at the U.S. decision to send exposed Americans to a quarantine facility in Kenya instead of bringing them home for monitoring and treatment — and what that reveals about confidence in domestic public-health systems.

Pathogens don’t create emergencies in isolation. They exploit the vulnerabilities we leave open for them.

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 between viruses to help prosecutors build a criminal case against a physician accused of intentionally infecting his former partner.

How can a virus become evidence?

This is the story of the case that asked whether a virus could testify.

Topics include:

And because this is Outbreak After Dark, there’s also a menu:

All recipes and citations in the companion blog post at infectiousdose.com

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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:

This episode also explores the human side of Ebola outbreaks: caregiving, fear, stigma, survival, and the difficult realities faced by affected communities.

Companion blog post with transcript, references, outbreak updates, and photographs from the 1995 Kikwit outbreak: Infectious Dose

Subscribe to the free weekly newsletter, Field Notes, for outbreak updates and behind-the-scenes context.

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 contact,” and precautionary public-health measures became so messy in real time.

Topics include:

This episode is less about headlines and more about learning how scientific understanding evolves while an outbreak is still unfolding.

Subscribe to weekly Field Notes to continue the conversation

Companion blog post with annotated citations at infectiousdose.com

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 like when the evidence is still coming in?

Topics include:

Heather also introduces a practical framework for understanding outbreak communication.

This episode is about resisting panic, avoiding false certainty, and rebuilding a clearer understanding of how science works when the story is still unfolding.

Heather will also be following the outbreak with updates in her free, weekly newsletter, Field Notes. Subscribe at the link if you want to join the conversation.

All citations in the companion blog post at infectiousdose.com