The Vector

August 29, 2019·29 min·2 clips

Colleen Evans reveals ticks that feed inside hippopotamus butts and survive underwater in sea snakes' ears.

First, there is the tick. The recap brings back muscle aches, crushing headaches, a bullseye rash, children with arthritis, and the awkward fact that ticks are still easy to misunderstand. Then the story moves inward. Lyme bacteria sit in the tick's midgut, compared to an astronaut in cryogenic sleep, while the tick travels. Skin warmth changes the message. Once the mouthparts enter the skin, the bacteria and other tick-borne pathogens get the signal that they are somewhere new. Blood becomes food. The tick feeds first, and that meal lets the bacteria multiply without hurting the tick. The hard part is the trip: the bacteria still need to move from the midgut toward the salivary glands before they can enter another host. Sam Telford ties the familiar twenty-four-to-forty-eight-hour advice to studies that removed ticks at intervals and checked for infection. Then the neat rule gets messier. People in Lyme World tell stories about short bites followed by illness, and experts treat the timing as a guideline, not a law. Twenty-three hours is possible, just less likely. Pre-fed ticks make it stranger: one animal can start the process before the tick drops off and bites again. The takeaway is uneasy but useful: anatomy, a meal, and a clock that does not behave like a clock.

As heard by us

A careful Lyme investigation that treats uncertainty as part of the story.

Patient Zero treats Lyme disease as a study in timing, temperature, and the small machinery inside a tick. It moves from expert explanation to reporting in Lyme, Connecticut, so the science stays grounded in the place that gave the illness its name.

Read the full review in PlayNext →

Why you'd press play

You want the Lyme story unpacked through field reporting and tick biology.

Read the full recommendation in PlayNext →

Listen to the show on

Apple Podcasts Spotify

Play clips from this episode More from Patient Zero