RESUMO
Introduction: Management and control of COVID-19 outbreaks in hospital settings represent a major challenge. Any suspicion of nosocomial transmissions require prompt investigations and control measures. Objectives: To describe the management of 2 consecutive clusters of patients presenting suspect symptoms of Covid-19 in a 19-bed psychogeriatric unit, hosting concomitantly 2 patients with SARS-CoV-2 infection confirmed by RT-PCR on nasopharyngeal swabs (lineage B.1.1.7, viral loads of 6.9E + 8 and 8.0E + 7 copies/ml, respectively) among whom one was a nosocomial case with persistence of a high viral load at day 14 (8.9E + 6 copies/ml). Methods: After identification of the SARS-CoV-2 cases, control measures were promptly applied. During the following weeks, the clinicians of the ward additionally reported 2 clusters of 3 patients with suspect symptoms. All of these suspect cases were isolated with Droplet Precautions and were investigated by a nasopharyngeal swab for SARSCoV- 2 testing. If the first SARS-CoV-2 RT-PCR was negative, a second test was performed within 24 h. Additionally, we proposed to complete investigations by an extended respiratory multiplex RT-PCR. Results: Among the 6 symptomatic patients, all had 2 consecutively negative SARS-CoV-2 RT-PCR. The respiratory virus panel test revealed a positive PCR for OC43 coronavirus in 5/6 patients, with viral load ranging from 3E + 5 to 3E + 9 copies/ml, confirming a nosocomial outbreak of a seasonal coronavirus. For the remaining patient, infection by OC43 coronavirus was considered possible, regarding the close contacts with positive cases during the hospital stay. Conclusion: Even if the actual Covid-19 epidemic setting should conduct to promptly research a SARS-CoV-2 infection in symptomatic hospitalized patients, this report highlights the possibility of cocirculation of different respiratory virus within the same ward. More extended microbiological investigations with specific RT-PCR analysis in symptomatic patients repeatedly tested negative for Covid-19, can conduct to a better understanding of nosocomial outbreaks. Sometimes a coronavirus can hide another!.
RESUMO
Introduction: The high transmissibility of SARS-CoV-2 is of particular concern for hospitals as hospitalized patients are at risk of severe COVID-19 and related death. Objectives: Describe the contact tracing activity related to nosocomial SARS-CoV-2 cases in our hospital. Methods: The Infection Control Unit received alerts for positive PCR results performed by the Microbiology laboratory in hospitalized patients. Nosocomial infections, occurring after at least 5 days of hospitalization, were further investigated. Contact tracing was performed via an institutional software allowing tracing index patients' movements and their roommates. Patients were considered “contacts” at risk and were placed in quarantine if they shared the same room with the index-case up to 72 h before index's first positive PCR or first symptoms. Contacts systematically had nasopharyngeal SARS-CoV-2 PCR testing at days 0, 10 counting from last contact with the index or at symptom onset. Results: Between November 1st 2020 until March 31st 2021, 322 nosocomial SARS-CoV-2 cases were identified, of whom 195 (61%) had previously been in contact with another known case while for 127 (39%) source of infection was unknown. Median time from admission to positive PCR was 13 days (IQR 8 - 25). Symptoms where present in 67% of cases. Median age was 76 years (IQR 64 - 84). Of all episodes, 75% were diagnosed in medical units (including 50 cases, 16% in geriatric sections),24% in surgical sectors and 1% in the ICU. Contact tracing activity identified 605 contacts with a median of 2 contacts per index case (range 0-19). Of these, 32% had a positive PCR result during follow-up. Conclusion: A thorough contact tracing with systematic PCR screening is necessary after detection of a nosocomial SARS-CoV-2 case as transmissibility is high and more than 1/3 of cases are asymptomatic. The non-identification of a source for more than a third of cases raises concerns of potential implication of healthcare workers in transmission.