If one day Pyongyang was normalized and open for business, then its resistant strain of tuberculosis would need to be contained.

With a flurry of recent bilateral summits, talk of North Korea potentially opening up abounded for a while in world capitals and think tanks. But would it really be a good idea for Washington to allow American companies to do business in North Korea one day? Is North Korea really in a position to open up in a way that benefits its people, the United States, and the world?

Pyongyang has not done enough to justify moving forward opening relations. It is in America’s interests to require conditions be met before pushing forward with greater engagement, not just for strategic and human rights reasons, but also for health concerns.

This is because North Korea has one of the highest rates of multi-drug resistant tuberculosis (MDR-TB) in the world. Despite accounting for just one-third of one percent of the world population, North Korea is the source of 2.2 percent of new cases of MDR-TB. Overall, its rate of tuberculosis is twenty incidents of MDR-TB per one-hundred-thousand people.

Tuberculosis is a legitimate health security concern for the United States because most tuberculosis outbreaks happen due to migration, often through air travel. In 2012, a forty-nine-year-old migrant from the Philippines infected at least thirteen people while he was on a temporary work visa in the United States. In 2016, the number of tuberculosis cases increased for the first time in twenty-three years. Addressing MDR-TB in other countries becomes important because even a small opening can result in a major disease vector. For instance, officials must recognize that tuberculosis can even spread via third-party countries like the Philippines.

North Korea is one of the most dangerous countries that can spread tuberculosis. More than sixteen-thousand North Koreans are infected with this highly dangerous strain of tuberculosis. “We will see an explosion of MDR TB,” warns Dr. Kee B. Park of Harvard Medical School. Within five years, in addition to previous estimates of the death poll, 155,000 to 210,000 more North Koreans will die. By 2030, Dr. Park estimates that 1 million in North Korea will die from tuberculosis alone, according to his calculations of system dynamics and agent-based modeling.

Addressing tuberculosis in North Korea and the United States is urgent, and, at the moment, increased business interactions would be disastrous. “It’s not just a North Korean issue. It becomes a global issue,” says Jon Brause, the director of the World Food Programme Washington Liaison Office, at a health security discussion of North Korea at the Center for Strategic & International Studies. Limited business interaction does not mean the United States should deny North Korea medical expertise or humanitarian aid. On the contrary, in response, the international community should pursue “a low-cost intervention that can be done by highly qualified NGOs,” argues Brause.

Why don’t we manage tuberculosis through airport screening? Unfortunately, pre-screening is impractical, and resources can and should be used more effectively elsewhere, argues a medical research paper of the World Health Organization (WHO)’s recommendations. Airports already have a hard time screening only the contacts of tuberculosis patients. Besides, you may well know from traveling, airport screening is “resource intensive and yields few positive results.” Furthermore, risks of tuberculosis at airports are similar to “other circumstances where people are together in confined spaces,” according to the WHO. In other words, it is more productive to tackle tuberculosis at its source than to monitor every traveler.

Tuberculosis is far from the only health crisis affecting North Korea that must be addressed before allowing frequent cross-border movements. It also has a high rate of hepatitis B and one-third of North Korean school children afflicted with intestinal parasites.

One might wonder, things cannot go that bad, can it? Well, we are about to find out as we continue on this path of foreign diplomacy. It is in America’s own interests to address health issues before conducting business with North Korea.