In 1997, Silvio Barbosa was relieving himself in an Amazon tributary. The Candiru from locating the stream of urea and swimming up his penis.

The Blood-Sucking Candiru Myth

This myth makes everyone cringe, and what makes is so aweful is that it is very believeable. For centuries, fishermen and local communities from around and along the Amazon river have told of a fish that can swim up your urethra from simply releaving oneself in the river. As such, most people living along the Amazon avoid urinating in the river. Imagine being attacked in such a provate way while having a pee in the woods!

According to the myth, the Candiru will swim up the urination stream and embed itself several inches inside the urethra. Obviously this is not a big fish, but why would any fish even want to do this? We will get to that later. While there are several variations of this myth, most of them have very little evidence but one. In every case we came across, the story was passed down from someone else. But what each story tells is that the poor person that managed to get the Candiru stuck inside their urethra died a painful, agonizing death.

What is the Candiru?

The Candiru (Vandellia cirrhosa) is also known as cañero, toothpick fish or the vampire fish. It is a small fish that does not usually get larger than five or six inches, but is very narrow when it is hungry but swells up after eating.

There is a lot of confusion on the classification of the Candiru large because the name Cadiru is casually used to refer to some Cetopsis catfish and Vandellia catfish. Both of which are in the order Siluriformes. While other small Cetopsis species are attracted known to swim up the urethra, the Vandellia cirrhosa is the most common species know for doing so.

The Candiru has barbels around its head that are designed to sense urea, which fish excrete from their gills. It is the gills that the Candiru is interested in, not some poor unsuspecting person that is urinating by the river. Normally the Candiru attach itself to the gills of fish and feed off the blood as it is a parasite in much the same way as a mosquitoes. Because they are transparent, it is very difficult to spot them in the water as they appear invisible.

When urinating it the water, the Candiru can sense the urea and immediately will focus on the source. And in the case of humans, this involves swimming far up the urethra in the penis and the vagina for women. Sinse the Candiru has sharp barbes, once it is inside, it cannot make it out the same way. Without medical treatment, fever can set it, swelling and finally sepsis resulting in a painful death. However, that is the legend. There is very little evidence supporting this claim. The little bit of evidence that there is has come under attack.

Candiru Attacks Silvio Barbosa

While there are a lot of rumours and stories behind this parasitic fish, including episodes on several shows including 1000 Ways To Die, River Monsters, BBC Deadly 60 and more. In 1997, Silvio Barbosa was relieving himself in an Amazon tributary. He was aware of the myth so he was not completely in the water.

However, this did not stop a Candiru from locating the stream of urea and swimming up it. he immediately tried to stop it from swimming in further, but only its tail was flipping back and forth outside and eventually lodging itself deep inside his urethra, with its tail one inch from the opening. Fear set in as he knew that this was a carnivorous fish and he feared that it would eat everything in site.

Silvio was far from medical assistance. When he did reach a hospital, they did not believe his claims that something had entered him while he was urinating. He was transfered from hospital to hospital because no one knew what was wrong. Silvio by this time had a fever. His bladder and testicles were swolle and he was in a lot of pain. Whats worse is that the Candaru was trying to eat its way out.

Dr. Anoar Samad Removes the Candiru

Dr. Anoar Samad believed his symptoms and rushed him into surgery. Due to the condition of the patient and the fact that the fish was beginning to rot, he decided to perform endoscopic surgery, which lasted some two hours. Watch the actual video below. The fish was later sent to the National Institute of Amazonian Research and was confirmed as the Candiru and also confirmed the myth of the river monster.

The Fact Behind the Myth

There are problems with five points to this story. The first is that it is simoly not possible for a fish to dart up the urine stream according to fluid dynamics. While it is possible that it might make a lucky jump, there is significant conjecture around this.

The second point of argument is that the Candiru in question was 133.5 mm in length and had a head with a diameter of 11.5 mm. it would require more force and leverage that is possible for the creature given the distance it had to jump, swim up the stream and force itself inside.

The third point concerns Samad’s claims the fish must have been attracted by the urine. however, this belief was discredited in 2001 by Spotte, Paulo and Jansen in, Experiments on the feeding behaviour of the hematophagous candiru, published in 2001.

The fifth point of concern is that the Candiru in question does not possess the right teeth or stron enough dentition to be able to chew through the ventral wall and into the scrotum as was claimed.

And finally, Samad claimed he had to snip the candiru’s graspin yet the sample sent away for analysis still had them present.