Kampala - The death toll for Uganda's mysterious disease has risen to 38 people, the Uganda Health Ministry announced that preliminary results from tests done at the Central Public Health Laboratories (CPHL), Uganda Virus Research Institute (UVRI), USAID, CDC Atlanta and WHO on specimens obtained from patients are negative for Ebola, Marburg, Congo Crimean Fever, Rift Valley and Typhoid. Further tests are being run to identify the cause of the illness.

As of December 3, 2010, there were 91 patients and 38 deaths.Thirteen people have died in northeastern Uganda from the unknown disease.

Investigations are continuing to determine the cause of the disease that appears to be similar to the Ebola and Marburg hemorrhagic viruses.

Ninety-one cases of the frightening illness have been reported in the remote Abim district. Due to the number of cases reported, the district has been labeled the epicenter of what many are calling it the “Abim disease.”

Of the 20 cases in Abim, eight have died, two are quarantined and another 10 have been discharged after their conditions improved, according to . Five more died in the neighboring Agago district.

“The victims usually die between three and five days, and are suspected to be highly contagious,” said Emmanuel Okech, a health official in Abim.

Symptoms include high fever, vomiting blood, passing bloody stool, convulsions and bleeding from openings like the nose and ears.

“We do not know what we are dealing with, we do not know what is happening, so we must respect the new measures which have been put in place,” said Dr. Emmanuel Otto, a health officer in Agago district, which has also been affected by the disease.

Health officials warn against communal hand washing, eating bush meat (meat from wild animals, especially monkeys and other primates) and discourage people from the local cultural practice of washing dead bodies before burial.

District health officials set up an isolation center for thos with the disease in Abim Hospital and another local health center.