Marcelo J. Frigerio

Argentine hemorrhagic fever: a primate model.

Experimental Junin virus infection of a New World primate, Callithrix jacchus, was evaluated. The virus produced anorexia, loss of weight, thrombocytopenia, leukopenia, and hemorrhagic and neurological symptoms and terminated in death. Virus was recovered from urine, blood samples and all tissues taken at autopsy. These preliminary observations show that several aspects of the experimental disease in C. jacchus are quite similar to severe natural Argentine hemorrhagic fever of man.

Epidemic Hemorrhagic Fever in Argentina.

A DISEASE of unknown etiology appeared a few years ago in the northwestern part of the Province of Buenos Aires. The clinical aspects were first described by Arribalzaga (1) and later by Duva (2), who suggested that it may be of leptospiral origin. The disease appeared again in 1958, and in May of that year we went to the city of Junin to study its clinical and etiological features. This study was the first to provide evidence of the virological nature of the causative agent (3). Later, Margni and co-workers, on the basis of little evidence, presented the opinion that poisoning by dieldrin, aldrin, or other products, might be an auxiliary factor (4). At a special meeting held in the University of Buenos Aires on December 19, 1958, we presented a full report of our work with the disease, defining it as new in Argentina and giving additional evidence of its virus etiology (5,6). This work has since been confirmed by other investigators (7). The clinical descriptions, which we had previously published, were recently confirmed by studies of the disease produced by inoculation of human volunteers. This research was conducted by two groups, working independently, and their reports appeared at about the same time (7,8).

Depression of “Jones Mote” type hypersensitivity by Junin virus

The effect of Junin virus infection on the active and passive delayed hyper-sensitivity of Jones Mote type in guinea pigs was studied. It was shown that in both types of hypersensitivity there is a suppression of the cutaneous reaction. It is suggested that the most probable effect of the virus is a direct action on immunological competent cells.