"Yesterday evening we finished examining samples taken from 30 patients who had returned from Wuhan on Sunday. None of the examined samples proved positive for the presence of the coronavirus" - Mr Kraska said.

"It means that these 30 patients, who are now at the military hospital in Wrocław, are not coronavirus carriers" - he added.

The patients will remain in the hospital and at the end of the week the tests will be repeated. The deputy minister stressed that this due to the WHO recommendations. He added that the decision to release them from the hospital is to be taken by the doctors overseeing the patients.

Planes with 30 Polish citizens evacuated from Wuhan landed in Wrocław on Sunday.

Deputy minister Kraska also confirmed that on Monday a Chinese child, who had returned from Beijing, was admitted to Warsaw's infectious diseases hospital. "The child is under observation. Samples have been taken. We're awaiting results" - he explained.

The chief of the National Institute of Public Health - National Institute of Hygiene Grzegorz Juszczyk, also present at the conference, reassured that the tests were very precise and allowed to detect coronavirus 2019-nCoV very quickly.

He informed that since last week 42 samples from patients who may have been infected have been checked.

Deputy minister explained that 35 people at risk of carrying coronavirus were under observation in hospitals, and 480 were being monitored by sanitary service. He reassured that all services were on high alert. "As I've been always saying , we cannot rule out that the coronavirus will eventually come to Poland. However, I'd like to stress with full confidence: all services are on high alert, we are prepared for every emergency" - Kraska said.