Panamanian Health Minister Camilo Alleyne said on Friday that toxins may have been the cause of the mystery illness, which had killed 18 Panamanians and affected another 28 in the country.
Alleyne said that tests on the 18 victims by U.S. scientists had revealed damage to kidney and nerve tissue, which suggested possible poisoning.
He added that the scientists had not identified the source of the poisons and there were no signs that the illness was contagious. Dengue fever, influenza, West Nile virus and other illnesses have been ruled out.
The illness, which starts with nausea, diarrhea and weakness, and progresses to acute kidney failure, paralysis and death, has struck mainly elderly men being treated for high blood pressure, diabetes and kidney disorders.
The health ministry declared a national epidemic alert on Tuesday.
Source: Xinhua