A wild iguana in Costa Rica bit a little girl as it tried to steal her piece of cake. Now, doctors say she has developed a rare bacterial infection.

• In a rare attack, an iguana bit a child for her cake in Costa Rica.
• Five months later, a strange cyst began to grow on the site the girl was bitten.

A girl's rare infection could have been linked to an encounter with an iguana that had a craving for cake, scientists suspect.

CNN reported that a scientific presentation on the unidentified 3-year-old girl's case will be given at the European Congress of Clinical Microbiology and Infectious Diseases this month.

Last March, the unnamed girl was on vacation with her parents in Costa Rica. Her parents gave her a cake as she hung out by the water. A wild iguana ran up to her, bit her finger and stole her cake.

"It was trying to mark its territory or something like that," Dr Jordan Kit Mah, a medical microbiologist at Stanford University told the Guardian.

Iguanas are typically harmless and herbivores, but this one appears to have developed a liking for sweets, CNN reported.

Her parents noticed that the bite was superficial but still took her to a local clinic, which disinfected the wound and gave her antibiotics. The wound healed, but five months later, they noticed a bump in the same spot.

While the girl said the bump did not hurt, it had grown to the size of a coin, and was a reddish-bluish color, the Guardian reported. The family took the child to the doctor.

At first, the parents hadn't thought the iguana bite had anything to do with it. Doctors suspected it might be a cyst but as it continued to grow, the parents realized the bump was in the same spot as the iguana bite, CNN reported.

The bump continued to grow and began causing mild pain, which sent the girl to an orthopedist. She has a biopsy which revealed a rare infection.

The little girl had developed Mycobacterium marinum, which typically causes tuberculosis-like illness in fish but rarely infects humans. Humans usually get this infection if they have open wounds and come into contact with contaminated water. Mah told CNN that he believes this is the first time a human has gotten this infection from an iguana bite.

"There is we know a lot about animal bites and bacteria, infections, following, let's say, dogs or cats, but there really isn't much for lizards, let alone iguana," he said. "I don't think people should be afraid, but doctors should be aware of the possibility."

He told the Guardian that he's not surprised it took this long for the girl to develop symptoms since the bacteria is very slow to grow and has a long incubation period.

The infection doesn't respond well to typical antibiotics but the little girl was put on rifampin, an antimicrobial, and clarithromycin, an antibiotic and according to Mah, is improving.

"Typically, with these infections, because they take a very long time to grow and they're a little bit more fastidious, you need to treat them for a longer period of time, sometimes several months," Mah told CNN. "So she's doing better. I wouldn't say 100%, but she's doing a lot better than she was initially."