German Foreign Minister warns of a serious threat from China's Covid wave.
Cooperation with WHO and European countries is necessary for transparency.
Germany has seen over 37.4 million Covid cases and 161,714 deaths.
France, Italy, UK impose restrictions on Chinese travelers.
France requires negative PCR or antigen test within 48 hours of departure.
Italy mandates antigen swabs and virus sequencing for Chinese travelers.
The UK requires a negative test before boarding and will test a sample of arrivals.
China condemns "discriminatory practices" in virus restrictions on travelers.
China calls for scientific, appropriate measures to address Covid.