When one mom gave her daughter a banana, she never expected her to end up in the hospital. However, the red streak inside the fruit was a warning sign.

Lissa Melin’s daughter had begun to feel unwell immediately after taking a bite of her banana. Baffled as to what was going on, Melin then inspected the piece of fruit more closely. And as she was horrified by what she saw inside the banana’s skin, the concerned mom proceeded to put her daughter in the car and drive her straight to the hospital.

Originally, though, the banana had been bought during what may have appeared at the time as just a regular shopping trip. In July 2015 Melin had visited her local branch of the British grocery store Morrisons and picked up a few things for herself and her family.

And after returning home from the store in Louth, England, Melin unpacked the groceries as normal. Little did she know, though, that one item in her shopping bags would cause unexpected chaos. It wasn’t until much later, in fact, that she would discover exactly what she had brought back.

Then a few days later, Melin and her eight-year-old daughter Dionne sat down for a snack when the most bizarre thing happened. Her daughter, who was normally a cheerful little girl, suddenly changed.

In particular, Dionne had taken a funny turn almost immediately after peeling a banana and taking her first bite of the fruit. Indeed, she subsequently complained to her mom that she was feeling sick. Melin, however, simply couldn’t understand what had caused her daughter to become so unwell all of a sudden.

At this point, Melin therefore decided to investigate the banana. She suspected that the fruit had something to do with her daughter’s sickness, given that her feelings of nausea had started immediately after taking a bite out of it. And when the concerned mom took a closer look at the banana, she was horrified at what she found.

Specifically, she discovered a bright red streak running through the center of the fruit. Unfortunately, her eight-year-old daughter hadn’t even noticed the red color and had continued to eat the banana. But once Melin saw the unusual feature, she immediately knew that something was up.

And although Melin was still unsure of what was going on, she was growing increasingly concerned for her daughter’s welfare. As a result, she grabbed the phone and dialed 111, the U.K. National Health Service helpline for non-emergency advice.

It was after that call that all the pieces of the puzzle then began to fall into place. There was something sinister about the banana that her daughter had eaten – and so Melin quickly decided that it was time to take Dionne to the hospital.

Melin duly bundled her sick daughter into the back of the car and sped off. Dionne, meanwhile, was still feeling sick, making her mom even more worried about her little girl. And all she had done was to give her child a banana from the supermarket.

Then, upon arrival at the hospital, little Dionne was checked over by medical personnel. But although Dionne’s symptoms were unusual, Melin was reassured by doctors that her daughter was not in immediate danger – which must have been a huge relief to the harried mom.

And, eventually, it was determined what exactly had created that red streak inside the banana: that is, the fungus Nigrospora. Fortunately, though, even if the fungus isn’t particularly pleasant to look at, it’s not actually dangerous to humans.

Indeed, while the fungus can make people feel ill, that may be because they’re repulsed at the idea of having eaten a rotten banana rather than suffering from anything more serious. And in Dionne’s case, she was checked over before being sent home from hospital with no lasting damage.

But despite Dionne’s full recovery, her mom wasn’t prepared to forget the incident that caused her family so much unnecessary stress. Speaking to local newspaper the Louth Leader in July 2015, Melin called for Morrisons to examine their fresh produce more thoroughly.

“Maybe Morrisons need to do some more vigorous checking so children – or anyone for [that] matter – doesn’t eat one again,” the mom said. Although Nigrospora may not be life-threatening, Melin felt that the supermarket should do more to ensure that affected fruit doesn’t reach customers.

Melin also told the newspaper that she hadn’t been the only person to discover the fungus in supermarket-bought bananas. “[A] friend [said] she also found one of these not long ago from Morrisons,” she added. But checking bananas for any tell-tale red stripes is easier said than done.

That’s because it’s impossible to tell if a given banana is infected with Nigrospora before it’s peeled. Unless supermarkets peel every banana and check the flesh before selling them, then, it will be a very difficult job to ensure that they are unaffected.

But that’s not to say that the supermarket chain wasn’t apologetic for Melin and her daughter’s ordeal. “We are sorry for Mrs. Melin’s daughter’s distress,” a spokesperson for Morrisons said to the Louth Leader. “This product did not meet our strict quality standards.”

The supermarket’s statement also addressed the fact that the fungus shouldn’t have made Melin’s daughter ill. “We would like to assure her that it is a naturally occurring mold which is not harmful to humans,” the chain’s spokesperson added.

What’s more, supermarket chain Lidl has also come under fire in the U.K. for selling bananas containing Nigrospora. And the German retailer, too, has issued an apology to the customer involved in finding the fungus. However, it’s worth bearing in mind that although finding Nigrospora inside your child’s banana would be a shock, Melin’s daughter’s health was never in any danger.