BEIJING, Sept. 2 -- A health official said Tuesday that Ebola had been ruled out after tests on 20 suspected cases were deemed negative as of Sunday.

The cases involved individuals showing symptoms of fever who were hospitalized as "observation cases of Ebola." They were cleared as not infected with the virus, said Li Dexin, a researcher with the Chinese Center for Disease Control and Prevention (CCDCP).

Of the 20 samples, nine were diagnosed with malaria and received timely treatment.

In order to contain the virus, the CCDCP set up a nationally qualified lab which can complete Ebola tests within five hours, Li said.

Also on Tuesday, China's National Health and Family Planning Commission released a guideline for medial workers in order to prevent them from infection.

Ebola, which spreads through mucus and other body fluids or secretions such as stools, urine, saliva and semen, has claimed more than 1,500 lives in Africa, including Guinea, Liberia, Sierra Leone and Nigeria.

The WHO describes it as the deadliest outbreak in the history of the disease.