HANTAVIRUS PULMONARY SYNDROME OUTBREAK IN ARGENTINA - MOLECULAR EVIDENCE FOR PERSON-TO-PERSON TRANSMISSION OF ANDES VIRUS

An increase of Hantavirus Pulmonary Syndrome (HPS) cases around a sout hwestern Argentina town and in persons living 1400 km away but in cont act with those cases was detected during the spring of 1996. In order to evaluate person-to-person transmission we compared the homology of PCR-amplified viral sequences of 26 Argentine and Chilean cases. Sixte en of them were epidemiologically linked cases and had the same sequen ce (Epilink/g6) in the S segment 3' noncoding region and in the M segm ent partial G1 and G2 region (a total of 1075 nucleotides). Contrarily , two geographical and contemporary but nonepidemiologically related c ases differed from Epilink/96 in the compared regions. No significant differences, such as glycosylation or hydrophilic pattern, were found between Epilink/96 and the other sequences. Nucleotide and deduced ami no acid sequence homologies between samples from southern Argentina an d Chile ranged from 90.9 to 100% and 96.4 to 100%, respectively. Phylo genetic analysis revealed that all the analyzed southwestern viruses b elong to the Andes lineage. Although human infection principally occur s via inhalation of contaminated rodent excreta, our results with Ande s Virus show the first direct genetic evidence of person-to-person tra nsmission of a hantavirus. (C) 1998 Academic Press.