A COVID-19 nosocomial cluster in a university hospital in southern Italy: a social network analysis
Keywords:
: COVID-19, contact tracing, healthcare workers, clusterAbstract
Introduction. Healthcare workers on duty at the hospital are at high risk of COVID-19 infection. However, despite the introduction of risk-lowering practices in the hospital setting, there have been many cases of SARS-COV-2 infection among Health Care Workers. Fast and efficient contact tracing and Sars-CoV-2 PCR-based testing of the close contacts of Health Care Workers with confirmed infections are essential steps to limit nosocomial outbreaks.
Methods. This cross-sectional study was conducted at Bari Policlinico General University-Hospital (Apulia, Italy) and describes the management of a cluster of SARS-COV-2 infections in three Operative Units. The contact tracing activities and the measures implemented to control the outbreak are described.
Results. Among the 186 Health Care Workers active in the cluster setting, there were 9 (4.8%) confirmed cases, including the index case. Due to the outbreak, three Operative Units were closed to limit virus circulation. Health Care Workers with confirmed infections tested negative after a mean of 28.0±6.6 days (range: 13–37) and none required hospitalization.
Conclusions. Protection of the health of Health Care Workers during the COVID-19 pandemic should be a public health priority. However, despite recent recommendations and the implementation of protective measures, SARS-COV-2 infections of Health Care Workers remain at a high rate, indicative of the continued high risk of cluster onset in the nosocomial setting.
References
1. World Health Organization (WHO). Q&A on coronaviruses (COVID-19). Updated 17 April 2020. Available on: https://www.who.int/ emergencies/diseases/novel-coronavirus-2019/ question-and-answers-hub/q-a-detail/q-a-coronaviruses [Last accessed: 2022 January 18].
2. Centers for Disease Control and Prevention (CDC). Frequently Asked Questions. Updated 3 July 2020. Available on: https://www.cdc.gov/ coronavirus/2019-ncov/faq.html#Basics [Last accessed: 2022 January 18].
3. World Health Organization (WHO). Coronavirus disease (COVID-19). Situation Report – 167. Available on: https://www.who. int/docs/default-source/coronaviruse/situation-reports/20200705-covid-19-sitrep-167. pdf?sfvrsn=17e7e3df_4 [Last accessed: 2022 April 4].
4. European Centre for Disease Prevention and Control (ECDC). COVID-19 situation update for the EU/EEA and the UK, as of 7 July 2020. Available on: https://www.ecdc.europa.eu/en/ cases-2019-ncov-eueea [Last accessed: 2022 April 4].
5. Centers for Disease Control and Prevention
(CDC). How to Protect Yourself & Others.
Updated 24 April 2020. Available on: https:// www.cdc.gov/coronavirus/2019-ncov/preventgetting-sick/prevention.html [Last accessed: 2022 January 18].
6. Centers for Disease Control and Prevention
(CDC). Interim Infection Prevention and Control Recommendations for Healthcare Personnel
During the Coronavirus Disease 2019 (COVID19) Pandemic. Updated 19 June 2020. Available on: https://www.cdc.gov/coronavirus/2019ncov/hcp/infection-control-recommendations.
html [Last accessed: 2022 January 18].
7. Chirico F, Nucera G, Magnavita N. COVID-19: Protecting Healthcare Workers is a priority. Infect Control Hosp Epidemiol. 2020 Sep; 41(9): 1117. doi: 10.1017/ice.2020.148. Epub 2020 Apr 17.
8. Wu Z, McGoogan JM. Characteristics of and Important Lessons From the Coronavirus Disease 2019 (COVID-19) Outbreak in China: Summary of a Report of 72 314 Cases From the Chinese Center for Disease Control and Prevention. JAMA 2020 Apr 7; 323(13): 1239-42. doi: 10.1001/jama.2020.2648.
9. European Centre for Disease Prevention and Control (ECDC). Epidemiology of COVID-19. Available on: https://www.ecdc.europa.eu/en/ covid-19/latest-evidence/epidemiology [Last accessed: 2022 January 18].
10. Italian Higher Institute of Health. COVID-19 integrated surveillance data in Italy. Available on: https://www.epicentro.iss.it/en/coronavirus/ sars-cov-2-dashboard [Last accessed: 2022 April 4].
11. Bays DJ, Nguyen MH, Cohen SH, et al. Investigation of Nosocomial SARS-CoV-2 Transmission from Two Patients to Health Care Workers Identifies Close Contact but not Airborne Transmission Events. Infect Control Hosp Epidemiol. 2021 Sep; 42(9): 1046-52. doi: 10.1017/ ice.2020.321. Epub 2020 Jul 3.
12. von Freyburg A, Hagedorn H, Brücher B, Schmidt A, Scherer MA. COVID-19-ClusterStudie an einem Lehrkrankenhaus: CoronaPandemie 2020 [COVID-19 cluster study at a teaching hospital]. MMW Fortschr Med. 2020 May; 162(9): 64-7. German. doi: 10.1007/ s15006-020-0482-z.
13. Apulia Region. Epidemiological Bulletin July 12 2020. COVID-19 epidemic. Available on: https:// www.regione.puglia.it/documents/65725/216593/
Bollettino+Covid_12072020.pdf/5f610d2d-a13221ba-01b4-9a595da96a66?t=1594550871223 [Last accessed: 2022 January 18].
14. Apulian region Government. Hospital reorganization of the Apulia region in accordance with D.M. n. 70/2015 and stability laws 2016-2017. Modification and integration of R.R. no. 14/2015. Deliberation of the regional council 23 January 2018, n. 53. Official Bulletin of the Apulia Region n. 24 of 13-2-2018. Available on: http://www. regione.puglia.it/documents/10192/8447931/ Bollettino+numero+32+-+Ordinario++anno+2017/2cb49cc5-0df8-42b0-8411-461afbd c196e;jsessionid=F840E34D9C00F44CC75293 874FC7D2C6 [Last accessed: 2022 January 18].
15. Apulia Region. Updating of the definition of COVID19 case. Ministry of Health circular n. 0007922 of 09 March 2020. Available on: https://www. sanita.puglia.it/documents/85675901/98897944/ Flow+chart+Covid-19/28850136-f4c0-436c-980a-e2ccf4b29640 [Last accessed: 2022 January 18].
16. European Centre for Disease Prevention and Control (ECDC). Contact tracing: public health management of persons, including healthcare workers, having had contact with COVID-19 cases in the European Union – second update 8 April 2020. Available on: https://www. ecdc.europa.eu/sites/default/files/documents/ Contact-tracing-Public-health-managementpersons-including-healthcare-workers-havinghad-contact-with-COVID-19-cases-in-theEuropean-Union%E2%80%93second-update_0. pdf [Last accessed: 2022 January 18].
17. European Centre for Disease Prevention and Control (ECDC). Infection prevention and control and preparedness for COVID-19 in healthcare settings. Fourth update – 3 July 2020. Available on: https://www.ecdc.europa.eu/sites/ default/files/documents/Infection-preventionand-control-in-healthcare-settings-COVID-19 _4th_update.pdf [Last accessed: 2022 January 18].
18. World Health Organization (WHO). Use of laboratory methods for SARS diagnosis. Available on: https://www.who.int/csr/sars/labmethods/en/ [Last accessed: 2022 January 18].
19. Bastian M, Heymann S, Jacomy M. Gephi: an open source software for exploring and manipulating networks. International AAAI Conference on Weblogs and Social Media. 2009. Available on: https://gephi.org/publications/gephi-bastianfeb09.pdf [Last accessed: 2022 January 18].
20. Bianchi FP, Vimercati L, Mansi F, et al. Compliance with immunization and a biological risk assessment of health care workers as part of an occupational health surveillance program: The experience of a university hospital in southern Italy. Am J Infect Control. 2020 Apr; 48(4): 36874. https://doi.org/10.1016/j.ajic.2019.09.024.
21. Vimercati L, Bianchi FP, Mansi F, et al. Influenza vaccination in health-care workers: an evaluation of an on-site vaccination strategy to increase vaccination uptake in HCWs of a South Italy Hospital. Hum Vaccin Immunother. 2019; 15(12): 2927-32. doi: 10.1080/21645515.2019.1625645. Epub 2019 Jul 25.
22. Jung J, Hong MJ, Kim EO, Lee J, Kim MN, Kim SH. Investigation of a nosocomial outbreak of coronavirus disease 2019 in a paediatric ward in South Korea: successful control by early detection and extensive contact tracing with testing. Clin Microbiol Infect. 2020 Nov; 26(11): 1574-5. doi: 10.1016/j.cmi.2020.06.021. Epub 2020 Jun 25.
23. Morawska L, Milton DK. It is Time to Address Airborne Transmission of COVID-19. Clin Infect Dis. 2020 Dec 3; 71(9): 2311-13. doi: 10.1093/cid/ciaa939.
24. Garzaro G, Clari M, Ciocan C, et al. COVID-19 infection and diffusion among the healthcare workforce in a large university-hospital in northwest Italy. Med Lav. 2020 Jun 26; 111(3):
184-94. doi: 10.23749/mdl.v111i3.9767.
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