Assessment of person-to-person transmission of hantavirus pulmonary syndrome in a Chilean hospital setting

Person-to-person transmission of Andes hantavirus among healthcare workers was reported in Argentina for the first time in 1996. To determine whether such transmission of the virus occurred during a 1997 outbreak of hantavirus pulmonary syndrome (HPS) in southern Chile due to Andes virus, we conducted a serological and epidemiological study in the Coyhaique Regional Hospital, where the majority of HPS patients were admitted. Workers in every department of the hospital were evaluated for immunoglobulin G (IgG) and IgM hantavirus antibodies using the enzyme-linked immunosorbent assay (ELISA). A standardized questionnaire was used to determine the type and extent of exposure to HPS patients, as well as other potential risk factors and previous febrile respiratory illnesses requiring hospitalization. Less than half (44%) reported always using gloves when touching patients or their secretions; respiratory protection was not used. Of the 319 participants (87.9% of those eligible), 12 (3.7%) had Ige antibodies. This finding is consistent with the antibody prevalence in the community in which the participants lived. Of the 12 positive healthcare workers, six reported contact with HPS patients. A similar exposure was found in those who tested negative [6/140 (4%) compared to 6/179 (3%), P=0.66]. There was no significant difference in the types of hospital activities performed or the number of hospitalizations for febrile respiratory illnesses between antibody-positive and antibody-negative individuals. These data suggest that there was no person-to-person transmission among healthcare workers during a recent outbreak of HPS in Southern Chile in 1997, despite the inconsistent use of any precautions against transmission.