No abstract

No abstract

Argentine hemorrhagic fever (AHF) is a rodent-borne illness caused by the arenavirus Junin that is endemic to the humid pampas of Argentina. AHF has had significant morbidity since its emergence in the 1950s, with a case-fatality rate of the illness without treatment between 15% and 30%. The use of a live attenuated vaccine has markedly reduced the incidence of AHF. Present specific therapy involves the transfusion of immune plasma in defined doses of neutralizing antibodies during the prodromal phase of illness. However, alternative forms of treatment are called for due to current difficulties in early detection of AHF, related to its decrease in incidence, troubles in maintaining adequate stocks of immune plasma, and the absence of effective therapies for severely ill patients that progress to a neurologic-hemorrhagic phase. Ribavirin might be a substitute for immune plasma, provided that the supply is guaranteed. Immune immunoglobulin or monoclonal antibodies should also be considered. New therapeutic options such as those being developed for systemic inflammatory syndromes should also be valuated in severe forms of AHF.

Phylogenetic analysis of a 292-nucleotide (nt) fragment of the hantavirus M genome segment from 36 rodent and 13 human samples from three known foci of hantavirus infection in Argentina was conducted. A 1654-nt fragment of the M genome segment was analyzed for 1 representative of 7 genetically distinct hantavirus lineages identified. Additionally, the nt sequence of the complete M genome segments of Lechiguanas, Oran, and Hu39694 hantavirus genotypes was determined. nt sequence comparisons reveal that 7 hantavirus lineages from Argentina differ from each other by 11.5%-21.8% and from Sin Nombre, Bayou, and Black Creek Canal viruses by 23.8%-26.5%. Phylogenetic analyses demonstrate that they form a unique, separate branch within the clade containing other New World sigmodontine-borne hantaviruses. Most Oligoryzomys-borne hantavirus genotypes clearly map together. The Oligoryzomys-borne genotypes Lechiguanas, Oran, and Andes appear to be associated with human disease. Oligoryzomys longicaudatus was identified as the likely rodent reservoir for Andes virus.

No abstract