At a briefing on Wednesday, lead surgeon Lee Cook-jong displayed photos showing dozens of flesh-coloured parasites - including one 27 cm (10.6 in) long - removed from the wounded soldier's digestive tract during a series of surgeries to save his life.
"In my over 20 year-long career as a surgeon, I have only seen something like this in a textbook," Lee said.
The parasites, along with kernels of corn in his stomach, may confirm what many experts and previous defectors have described about the food and hygiene situation for many North Koreans.
"Although we do not have solid figures showing health conditions of North Korea, medical experts assume that parasite infection problems and serious health issues have been prevalent in the country," said Choi Min-Ho, a professor at Seoul National University College of Medicine who specialises in parasites.
The soldier's condition was "not surprising at all considering the north's hygiene and parasite problems," he said.
The soldier was flown by helicopter to hospital on Monday after his dramatic escape to South Korea in a hail of bullets fired by North Korean soldiers.
He is believed to be an army staff sergeant in his mid-20s who was stationed in the Joint Security Area in the United Nations truce village of Panmunjom, according to Kim Byung-kee, a lawmaker of South Korea's ruling party, briefed by the National Intelligence Service.
North Korea has not commented on the defection.
While the contents of the soldier's stomach don't necessarily reflect the population as a whole, his status as a soldier - with an elite assignment - would indicate he would at least be as well nourished as an average North Korean.
He was shot in his buttocks, armpit, back shoulder and knee among other wounds, according to the hospital where the soldier is being treated.
'THE BEST FERTILISER'
Parasitic worms were also once common in South Korea 40 to 50 years ago, Lee noted during his briefing, but have all but disappeared as economic conditions greatly improved.
Other doctors have also described removing various types of worms and parasites from North Korean defectors.
Their continued prevalence north of the heavily fortified border that divides the two Koreas could be in part tied to the use of human excrement, often called "night soil."
"Chemical fertiliser was supplied by the state until the 1970s, but from the early 1980s, production started to decrease," said Lee Min-bok, a North Korean agriculture expert who defected to South Korea in 1995. "By the 1990s, the state could not supply it anymore, so farmers started to use a lot of night soil instead."
A lack of livestock, however, made it difficult to find animal waste, said Lee, the agriculture expert.
Even harder to overcome, he said, is the view of night soil as the "best fertiliser in North Korea," despite the risk of worms and parasites.
"Vegetables grown in it are considered more delicious than others," Lee said.
The medical briefing described the wounded soldier as being 170 cm (5 feet 5 inches) and 60 kg (132 pounds) with his stomach containing corn. It's a staple grain that more North Koreans may be relying on in the wake of what the United Nations has called the worst drought since 2001.
Imported corn, which is less preferred but cheaper to obtain than rice, has tended to increase in years when North Koreans are more worried about their seasonal harvests.
Despite the drought and international sanctions over Pyongyang's nuclear programme, the cost of corn and rice has remained relatively stable, according to a Reuters analysis of market data collected by the defector-run Daily NK website.
Since the 1990s, when government rations failed to prevent a famine hitting the country, North Koreans have gradually turned to markets and other private means to feed themselves.
The World Food Programme says a quarter of North Korean children 6-59 months old, who attend nurseries that the organisation assists, suffer from chronic malnutrition.
On average North Koreans are less nourished than their southern neighbours. The WFP says around one in four children have grown less tall than their South Korean counterparts. A study from 2009 said pre-school children in the North were up to 13 cm (5 inches) shorter and up to 7 kg (15 pounds) lighter than those brought up in the South.
"The main issue in DPRK is a monotonous diet - mainly rice/maize, kimchi and bean paste - lacking in essential fats and protein," the WFP told Reuters in a statement last month.
(Additional reporting by Seung-woo Yeom, James Pearson, Heekyong Yang, Hyunjoo Jin, Soyoung Kim, Writing by Josh Smith, Editing by Bill Tarrant)
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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