“People cured of Covid-19, despite negative PCR and IgM antibody tests and green QR code, will be transferred to immediate hospital quarantine for several weeks upon entry and subjected to extensive examinations,” the German Foreign Ministry website read Thursday.

This could also affect people “who still have antibodies due to an undetected Covid-19 infection.”

The same could apply to travellers arriving on the same flight as a person who tests positive for Covid-19, it said.

“Medical measures from the Chinese side are invasive and often include CT scans in addition to sometimes daily blood draws.”

Non-essential travel to China is “discouraged,” the statement added.

In Beijing diplomatic circles, there was talk of a case where a traveller with Covid-19 antibodies, which show that one has recovered from the disease, was said to have run into problems as a result of a vaccination.

The Sueddeutsche Zeitung German newspaper reported that a German citizen who entered China in January had recovered from Covid-19, but had been detained in a hospital since mid-January because of a positive IgG antibody test.

China has largely closed its borders to foreigners since March, but Germans with valid residence permits can enter for work or family reunification.

Various tests are required shortly before departure. Upon arrival, between two and four weeks of quarantine are ordered at a hotel or central facility.