Monrovia, Ramadan 18, 1435, July 15, 2014, SPA -- Thirteen people died of Ebola in Liberia this week, the health ministry reported Tuesday, bringing the death toll to 94, dpa reported. Suspected cases in Liberia increased from 143 to 163 in the past seven days, said Tolbert Nyenswah, a health ministry official. The deadly virus continues to spread across West Africa, where more than 500 people have died. The World Health Organisation reported more than 850 Ebola cases in Guinea, Liberia and Sierra Leone, calling the outbreak "a major regional threat, unprecedented in duration and in scale." Ebola, which causes massive haemorrhages and has a fatality rate of 90 per cent, is one of the most contagious and terrifying viral diseases. It is transmitted through blood and other body fluids. --SPA 16:00 LOCAL TIME 13:00 GMT www.spa.gov.sa/w