Story highlights A month ago, South Korean man believed to be "patient zero" walked into hospital

South Korea reports 138 confirmed cases and 14 deaths

Seoul, South Korea (CNN) The rate of contagion of Middle East Respiratory Syndrome has slowed in South Korea, a health official said Saturday, and may be on its way down. But the outbreak is not completely over.

The outbreak has been "large and complex" and "more cases should be anticipated," an official told reporters.

Exactly a month ago, a South Korean man walked into a hospital complaining of a cough and fever.

The 68-year-old patient, who had just returned from four Middle Eastern countries, went from facility-to-facility before getting properly diagnosed. He would become "patient zero" of South Korea's outbreak of MERS, which has so far reported 138 cases.

The outbreak has sparked international concern, shuttered more than 3,000 schools and stalled the country's economy.

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