Researchers take part in a drill at the newly-completed lab in Wuhan, capital of central China's Hubei Province, Jan. 30, 2015. China completed its first high level biosafety laboratory based in Wuhan Saturday in Wuhan after more than a decade of construction. The lab will be used to study class four pathogens (P4), which refers to the most virulent viruses that pose a high risk of aerosol-transmitted person-to-person infections. (Xinhua/Yin Gang)