A wave of tuberculosis cases hitting the Kansas City, Kansas, metro area has become the largest documented TB outbreak in the United States since monitoring began in the 1950s, according to the state health department.

Dozens of active and latent TB cases have been linked to the outbreak dating back to last year, local health officials say.

"More than 80% of TB disease cases in the United States result from longstanding, untreated latent TB infection," TB said. According to the World Health Organization, about half of all people with TB can be found in eight countries: Bangladesh, China, Indonesia, Nigeria, Pakistan, Philippines and South Africa.