Background: A mysterious disease spread over Cuba from 1991 to 1993, the cause of which has not been fully established. Major symptoms were the same in patients with the Cuban disease as in patients with subacute myelo-optico-neuropathy (SMON), which had occurred in Japan nearly 30 years ago and from which Inoue-Melnick virus (IMV) type 1 was first isolated. We investigated the presence of IMV in cerebrospinal fluid samples of patients with this epidemic neuropathy in Cuba.
Methods: The established method for detecting IMV in MRC-5 fibroblasts was used throughout the study, which was conducted in two independent laboratories, one in Buffalo, NY, and the other in Kyoto, Japan. The cerebrospinal fluid samples of 20 patients and four controls were provided by Cuban researchers.
Results: All cerebrospinal fluid specimens from 20 Cuban patients tested were positive for IMV type 2 (100%), and four cerebrospinal fluid specimens from Cuban controls were negative for IMV (0%). These clear-cut results were identical in both laboratories.
Conclusion: Our study indicates an important association of IMV type 2 with patients of this Cuban epidemic. The etiologic role of IMV type 2 in the epidemic neuropathy in Cuba, along with weak cytopathic effect viruses isolated by the Cuban group, remains to be elucidated.