A Hong Kong hiker washed her face in a freshwater stream, not noticing that a leech had wormed its way into one of her nostrils, according to the Hong Kong Medical Journal.
Unaware she was playing host to the creature, the 55-year-old woman only consulted a doctor when her nose started bleeding intermittently about two weeks later.
The unusual case occurred in 2003 but doctors highlighted it in this month’s edition of the journal, where they discussed how to remove live leeches from human nasal passages using anaesthesia.
The first doctor the woman saw could not find anything wrong and it was only when she visited a second doctor that he saw the five-centimeter (two-inch) leech peeking out of her left nostril.
According to the article, doctors only managed to remove the stubborn bloodsucker with forceps after applying anaesthesia to the woman’s nose.
“Direct removal of a live leech might be difficult because of its powerful attachment to the mucosa and its slimy and mobile body,” the journal said.