(CNN) -- Health officials reported four more cases of a dangerous new virus in Saudi Arabia on Tuesday.
Three of the patients diagnosed as having the novel coronavirus, or nCoV, are still being treated, a statement on the Saudi Health Ministry website said. The fourth has been discharged from a hospital.
All four cases were in Saudi Arabia's Eastern province, the statement said.
NCoV was recently found for the first time in humans, and scattered cases have occurred across parts of the Middle East, particularly Saudi Arabia.
It has proved deadly in more than half of the confirmed cases so far, the World Health Organization said.
As of Sunday, the WHO had been informed of 34 laboratory-confirmed cases of human infection with nCoV worldwide since last September, including 18 deaths, it said.
Coronaviruses, which are common around the world, often cause colds.
The novel coronavirus acts like a cold in attacking the respiratory system, the Centers for Disease Control and Prevention have said. But symptoms are severe and can lead to pneumonia and even kidney failure.