A 62-year-old Swedish woman had during the flight from Lisbon informed co-passengers that she had left a Portuguese hospital where she had been held under surveillance due to suspicion she was suffering from meningitis.

“They were a bit nervous. We called the doctors, and when the plane landed we didn’t take it to the gate but to another part of the airport,” Arne Aabeck, the Copenhagen chief inspector in charge of the case, told AFP.

The Air Portugal flight, carrying 59 passengers and four crew members, landed around 2:30 pm (1330 GMT) and the passengers were not allowed off the Airbus 319 plane until 5:00 pm, he said.

“The doctors said you have to be together with the person with meningitis for at least eight hours (before being infected). That is why we are no longer worried,” he said, adding that the sick passenger had been taken to a Danish hospital by ambulance.

“The passengers have been informed by a doctor what symptoms to look for in case,” Aabeck said, adding it was unclear how the Swedish woman had left the hospital in Portugal.

“She just left. I don’t know if she escaped,” he said.

Meningitis is an inflammation of the protective membranes covering the central nervous system.

While some forms are mild, meningitis is a serious condition if the inflammation is close to the brain and spinal cord. It can be very contagious and can lead to death if untreated.