gms | German Medical Science

Objectives: Severe acute respiratory syndrome (SARS) is a viral respiratory illness caused by a coronavirus, called SARS-associated coronavirus. There is summarised the experience obtained to date with testing patients suspected of the SARS coronavirus infection. Nasopharyngeal swabs, nasopharyngeal lavage fluid, urine, stool, acute and convalescent blood samples were collected from the suspected patients.

Methods: The patients were tested as recommended by the WHO guidelines - the samples were analysed for the presence of SARS coronavirus and other possible viral respiratory pathogens. Based on the WHO requirements, the following criteria had to be met: either at least two different types of specimens positive for SARS-CoV or two SARS-CoV positive specimens of the same type if samples were collected at different time during the infection. Samples had to be unambiguously positive in PCR. Positive results of the same specimen tested by two different procedures had been also taken in consideration as an alternative. Isolation of the virus from the respective cell culture confirmed electron-optically and at least a four-fold increase in antibody level in and convalescent serum in comparison with the acute serum samples were unambiguously indicative of SARS etiology.

Results: Altogether 32 quarantined persons suspected of SARS infection were tested. They either showed positivity for type A influenza virus, respiratory syncytial virus, picornaviruses, herpesviruses, adenoviruses, non-SARS coronaviruses. Mycoplasma pneumoniae, Chlamydia pneumoniae and other bacterial infections were tested as negative. Only one of the patients tested was reported by the standard way as a SARS suspected case. Since SARS-CoV infection was not confirmed by following tests, the patient was excluded from the WHO and EU databases. This severe case of respiratory infection with a positive travel history is presented as a case report.

Conclusion: The test system used enabled establishment of preliminary laboratory diagnosis within 24 hours from patient admission and consequently institution of adequate therapy and adoption of anti-epidemic measures. SARS infection was not detected in any of the patients tested. The algorithm used in patient laboratory testing proved as an effective in practice.