Spanish health officials have recommended that physicians stop all use of rapid response coronavirus test kits after a batch bought from China failed to identify contagious people.

The Spanish Society of Infectious Diseases and Clinical Microbiology issued the recommendation after it was revealed that test kits from the Chinese firm Bioeasy presented a sensitivity of 30%, meaning that only 30% of those who have COVID-19 tested positive for it. Most tests, including rapid influenza tests in the United States, require a minimum sensitivity of 80%.

Spain purchased more than 640,000 coronavirus test kits from China and South Korea, which deliver results in 10 to 15 minutes. It is not clear how many of those tests were from Bioeasy, but the firm has sold kits to several other countries, including Georgia.

The Chinese embassy in Spain distanced itself from Bioeasy after the announcement was made. Chinese officials said they did not recommend Bioeasy products to Spain and noted that China's National Administration of Medical Products had not approved the company for sales.

Chinese officials also noted that test kits being donated from China to other parts of the world do not include any from Bioeasy. China announced it would be donating its stockpile of test kits following a decline in the number of new cases coming from Wuhan.

Some of those donated test kits, however, have been found to be faulty. The Czech Republic found that 80% of the test kits it received from China were inaccurate.

Spanish medical professionals were recommended to return to using tests that take longer to procure a result. Spain has one of the worst outbreaks on the planet and follows only Italy in total deaths with more than 4,100 who have died after contracting the disease.