"A laboratory is being installed in Luebo. We can probably start analysing from tomorrow (Tuesday)," World Health Organisation spokesman Cristiana Silvi told AFP by telephone from Luebo.
Luebo is about 125 kilometres (77 miles) northwest of Kananga, the provincial capital of the West Kasai region, where nine cases of the Ebola virus were confirmed by the WHO last week.
Another lab will be installed in nearby Mweka "but we have had difficulties transporting material because of the bad state of the roads," she added.
The two laboratories will allow a precise diagnosis within two to six hours, pinpointing the pathology and for the first time giving an idea of the range of the Ebola epidemic.
They are being installed by specialists from the Center for Disease Control (CDC) in Atlanta, US, and the National Public Health Agency of Canada.
The WHO confirmed nine new Ebola cases, five cases of typhoid fever and one case of bacterial dysentery disease Shigella in western Kasai.
Symptoms similar to that of Ebola -- high temperature, bloody diarrhoea, visible hemorrhaging -- were first seen on April 27 in the Kampungu region of West Kasai.
Since then, at least 174 people have died out of nearly 400 cases of patients suffering symptoms from various illnesses including Ebola, Shigella, acute malaria or gastro-enteritis, according to a new WHO toll.