GENEVA: The MERS outbreak in South Korea is a “wake-up call,” the World Health Organization warned Wednesday, saying that a lack of knowledge and substandard controls in hospitals had contributed to the spread of the disease.

The WHO urged all countries to be more vigilant as South Korea reported its 20th death from the Middle East Respiratory Syndrome virus, and criticism grew of its efforts to contain the crisis. “The outbreak really should serve as a wake-up call for countries,” WHO assistant director general Keiji Fukuda said after an emergency committee meeting.

“All countries should always be prepared for the unanticipated possibility of outbreaks like this and other serious infectious diseases,” a WHO statement said.

The warning came as alarming reports emerged in South Korea of new cases that had slipped through quarantine measures that already affect thousands.

And on Tuesday, German authorities reported that a national had died after contacting MERS during a trip to Abu Dhabi, but said there was no indication the virus had spread.

The WHO’s emergency committee meeting held Tuesday concluded that a lack of awareness about the virus among health workers and the public in South Korea was a major contributing factor to its rapid spread.

Others included the fact that MERS patients had been kept in crowded emergency rooms for long periods, and the practice in South Korea of going to multiple hospitals for second and third opinions on diagnoses and treatment — so-called “doctor shopping.”