BEIJING, Feb. 20 (Xinhua) -- Two teams of experts sent by the World Health Organization (WHO) were working with their Chinese counterparts in China's Guangdong and Sichuan provinces, respectively, from Feb. 18 to 19, said China's health authority on Thursday.

The experts visited local medical institutes and disease control and prevention organizations for field research, said Mi Feng, spokesperson for the National Health Commission, at a daily press conference.

The experts also held talks with the provincial and municipal health authorities, said Mi.