Monrovia, Shawwal 25, 1435, August 21, 2014, SPA -- Two Ebola-infected Liberian doctors and one nurse, who are being treated with experimental drug ZMapp, are showing signs of improvement, dpa quoted the Health Ministry as saying. The condition of the nurse and one of the doctors had improved substantially, according to assistant health minister for preventive services, Tolbert Nyenswah. The condition of the second doctor remained serious but had also improved. -- SPA 21:16 LOCAL TIME 18:16 GMT www.spa.gov.sa/w