Since a truce stopped the Korean War in 1953, contact between North and South Koreans has been rare, but every year hundreds of North Korean defectors cross into the South. Now, 473 North Koreans are officially in the South as part of an Olympic delegation including 22 athletes in Pyeongchang.

South Korea is wealthy, a democracy, and one of the most technologically advanced nations on the planet. Imagine the culture shock for the North Korean delegation who have come from a sealed-off, poverty-stricken, communist state.

Choi Hyun-Mi, the world's super featherweight boxing champion, has been undefeated since she went professional a decade ago in South Korea. But Choi's boxing career actually began in North Korea as a 9-year-old. She told CBS News' Holly Williams government coaches took her to live in a training camp where she competed against other girls for rice to feed their families. Choi and her parents eventually escaped their brutal regime, smuggled out through China like thousands of others.

Last November, one North Korean soldier took a much riskier route when he ran across the fortified border with South Korea under fire from fellow troops.

Dr. John Cook-Jong Lee is the trauma surgeon who saved the 24-year-old soldier's life. He had multiple gunshot wounds and lost half the blood in his body. Then, he discovered another problem: more than 50 parasitic worms in his body. Even the soldier, a member of North Korea's elite, was underfed and hadn't had a routine checkup.

"It means that the North Korean's national healthcare system is not working properly," Lee said. He called it "broken."

The North Korean athletes competing at these Olympics are also privileged citizens. But most – if not all of them – will be seeing their wealthy, democratic neighbor for the first time.

Asked if she thinks that some of the North Korean athletes might try to defect while at the Winter Games, Choi told Williams they know the government would take their families hostage. She said they'd be putting their families at risk.

The North Korean athletes will also be constantly chaperoned by North Korean officials, Choi said, making defection close to impossible.