The Poopy Tomatoes, Part 3

Who'da thunk there would be a part three to this story? (See parts 1 and 2, here and here.)

My parents came to visit about a month ago, to see their new grandson and to spend the holidays. I was still on holiday break, but my husband had gone back to work already.

"See any interesting cases at work today?" my dad asked my husband.

"Not really..." my husband replied, but then told them about a twitter feed, @radiopaedia, that shows an interesting radiology finding once a day. Then he had an idea. He showed them this CT scan:

CT scan showing numerous cysts from cysticercosis. (eMedicine)

My parents were duly impressed. He explained that these cysts are from the pork tapeworm, Taenia solium.

Scolex of Taenia solium. Shudder. (Source.)

Humans become infected when they eat raw or undercooked pork. Infected hosts then shed ova in their stool, and when these ova are ingested, the parasite can then go to the brain and cause cysts which can then lead to seizures.  This parasitic infection is hence continued by the fecal-oral route since the tapeworm's eggs are in the infected human's feces.

Life cycle of T. soleum. (CDC)

"And that's one reason why you shouldn't fertilize with human feces," my husband concluded.

"But we don't eat pork," argued my mother.

"You don't have to. When somebody else eats contaminated pork, it's their feces that contain the parasite eggs. When you fertilize with feces, the eggs contaminate fruits and vegetables that are grown in that soil, and when you eat those fruits and vegetables, you can get the parasite."

"But the vegetables are on the plants, and the soil is on the ground."

My husband then pointed out that the ova can be spread simply by insects landing on the ground and then on the produce.

"It must be so rare. I have never seen this before."

"Actually, it's pretty common. And why would somebody who presents with acute seizures or severe headache and encephalopathy present to you?" my husband questioned. My mother has an outpatient Internal Medicine practice. "They are going to be in the ER being seen by neurology."

At this point, my dad started getting very concerned. "Maybe we should get CT scans to see if we have it."

"Well, we stopped fertilizing that way 6 months ago," my mom claimed.

"Doesn't matter," my husband said. "The soil is already contaminated."

"Well, how do we get rid of it?"

"I don't know. I'm not a farmer!" My husband sighed. "See, this is why I'm worried about bringing our son to your house in California. Also, it makes me concerned that you guys don't use soap to wash dishes, so all of the dishes are basically breeding grounds for bacteria."

"Oh, and soap kills bacteria?" my mom scoffed.*

Waaaiiiiit a second. Back up. Apparently my mom started a Hepatology fellowship, but then switched to Infectious Disease. Infectious Disease. Granted, she didn't finish the fellowship because she became pregnant with my little sister. Maybe they don't learn about parasites or the benefits of SOAP until the end of the fellowship, because my mother doesn't know about either!

My parents finally left later that evening, very disturbed and hopefully will never fertilize with human poop again. (I am still not going to eat anything from that garden though...)

*sidebar: technically, regular soap does not "kill" bacteria, but allows it to detach from our skin/dishes and then get washed off with water.