RESUMO
Although viral replication and overwhelming immune responses are believed to contribute to the progression of severe acute respiratory syndrome (SARS), little is known about the temporal relationship between viral load, ribavirin, proinflammatory cytokines, and clinical progression. We report that ribavirin was not effective in reducing the SARS coronavirus load in 3 of 8 probable cases studied and that elevated levels of interleukin (IL)-6 and IL-8 subsequent to the peak viral load were found in 8 and 6 cases, respectively. The nadir lymphocyte count during lymphopenia, the peak level of lactate dehydrogenase, and the peak density of pulmonary infiltrates lag further behind the peak viral load by a median of 4, 5, and 3.5 days, respectively. These findings provide important information for therapeutic strategies to treat SARS.
Assuntos
Interleucina-6/sangue , Interleucina-8/sangue , Ribavirina/uso terapêutico , Síndrome Respiratória Aguda Grave/tratamento farmacológico , Carga Viral , Adulto , Antivirais/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Fatores de TempoRESUMO
The severe acute respiratory syndrome-associated coronavirus (SARS-CoV) is thought to be transmitted primarily through dispersal of droplets, but little is known about the load of SARS-CoV in oral droplets. We examined oral specimens, including throat wash and saliva, and found large amounts of SARS-CoV RNA in both throat wash (9.58 x 10(2) to 5.93 x 10(6) copies/mL) and saliva (7.08 x 10(3) to 6.38 x 10(8) copies/mL) from all specimens of 17 consecutive probable SARS case-patients, supporting the possibility of transmission through oral droplets. Immunofluorescence study showed replication of SARS-CoV in the cells derived from throat wash, demonstrating the possibility of developing a convenient antigen detection assay. This finding, with the high detection rate a median of 4 days after disease onset and before the development of lung lesions in four patients, suggests that throat wash and saliva should be included in sample collection guidelines for SARS diagnosis.