What is Brucellosis? All about the disease highlighted in All Creatures Great and Small Season 4

All Creatures Great and Small is based on James Alfred Wight's series of books and experiences as a veterinary surgeon in 1940s to 1990s England. The series, which follows an aspiring young vet named James Herriot, is currently in its fifth season on MASTERPIECE on PBS. Set in 1930s Yorkshire, James is hired as a vet at Skeldale House in the village of Darrowby.

All Creatures Great and Small follows the trio of vets, Siegfried, James, and Tristan, as they try to figure out what's wrong with the animals in Darrowby. One of the cases they came across is brucellosis in the Crabtree farm in Season 4. Brucellosis is a highly infectious bacterial disease in cattle that can cause infertility or fetal death. It's a case that will leave a lasting impact on James.

It turns out that the disease can also transmit to humans and cause a miscarriage, which was worrying for the Skeldale household because James' wife, Helen, was pregnant at the time.

---

What is brucellosis in All Creatures Great and Small?

In All Creatures Great and Small Season 4, James and Richard Carmody head out on a farm call at the Crabtrees because one of the cows, Elsie, lost one of her calves. Upon examining Elsie, Carmody immediately thinks that she has brucellosis.

He tells James all about what he learned from reading up on the disease—it's a bacterial infection caused by bacteria called Brucella. It mainly affects cattle, swine, dogs, goats, and sheep. It's highly contagious and doesn't have any treatment yet, per Carmody in the series. They have to quarantine and disinfect the entire farm to keep the disease from spreading.

Brucellosis, he says, can also jump from animals to humans if they are exposed to infected animals. And brucellosis in humans has similar side effects as those animals infected by it, including miscarriages in women. James Herriot's wife, Helen, who just shared the news about being pregnant, thinks she is infected with brucellosis after helping with the birth of the Crabtree's cow.

---

James Herriot unknowingly got brucellosis in All Creatures Great and Small Season 5

It turns out that Helen isn't the one they have to worry about when it comes to brucellosis. After waiting for days for the result of Helen's blood test, they find out that she isn't infected and her baby is safe. In Season 5 of the series, the brucellosis case returns, but this time, it's James who's infected by it.

While at RAF Abingdon in All Creatures Great and Small Season 5 Episode 1, ready for a practice mission, James suddenly collapsed to the ground. The doctor diagnosed him with brucellosis, and James thinks he got it back from the Crabtree farm. But because he wasn't feeling any symptoms at the time, he didn't think of getting a blood test like they did for Helen.

Diagnosed with brucellosis, James is deemed less than 100% fit as an aircraft pilot, leaving him on ground duty, which eventually leads him out of RAF Abingdon and back to Darrowby. In All Creatures Great and Small Season 5 Episode 6, James experiences a bout of brucellosis, where he becomes delirious and starts to hallucinate about Banerjee.

But like the doctor told him in Episode 1, the symptoms, which include fever and delirium, will pass and become milder and further apart over time. Also, there's no risk of him passing the illness to other people.

---

Catch All Creatures Great and Small Season 5 streaming on MASTERPIECE on PBS, with the past four seasons available on PBS Passport.