Of the 119 cases, 80 were hospital staff made up of mostly nurses and nursing students during the period between 9 March and 30 April 2020.
The investigation came after the Glenwood hospital was temporarily closed following a Coronavirus outbreak.
The investigation found that the outbreak likely began through transmission from a patient being assessed for Covid-19 in the emergency department to another patient being admitted at the same time with a suspected stroke.
The virus then spread widely through the hospital, involving patients and health care workers in at least five different wards.
The investigation was led by academics from the University of KwaZulu-Natal Dr Richard Lessells, Professor Yunus Moosa and Professor Tulio de Oliveira, experts in infectious diseases, epidemiology and viral genomics.
By generating and analysing the genetic sequence of SARS-CoV-2 (the virus that causes the Coronavirus/Covid-19 disease), they were able to create a timeline of how the virus was spread, and which patients and wards it went through.
They found that all 18 DNA sequences from the outbreak were almost identical, pointing to a single source of infection.
'To us, our findings highlighted how easily and quickly this virus can spread through a hospital. The initial spread of the virus was not recognised at the time, because the first patient who we think was infected in the emergency department was not initially suspected of having Covid-19. She did not have any of the typical risk factors and initially only had fever without cough or other respiratory symptoms,' said Lessels.
Lessels said by the time the patient was diagnosed with Covid-19, she had already infected other people.
The investigation also found that the outbreak spread to a local nursing home (four residents) and an outpatient dialysis unit (nine patients and eight staff members) operated by the National Renal Care.
'This highlights the risk that outbreaks like this become what we call amplifiers' of transmission, that is they fuel transmission in the wider community,' said De Oliveira.
The NRC is currently building an outpatient renal dialysis unit at St Augustine where it will separate patients into different zones according to their Covid-19 status.
The report makes a couple of suggestions that could be used as a blueprint for other hospitals to avoid similar outbreaks:
- Hospitals need to establish separate zones (and separate entry points) for people who have confirmed COVID-19 (red zone), people who might have COVID-19 (yellow zone), and people who are unlikely to have COVID-19(green zone).
- Vigilance throughout hospitals for acute respiratory illness, especially in green zones where patients considered low risk for COVID-19 have been admitted.
- Limiting the non-essential movement of patients between and within wards and limiting the movement of staff between different wards.
- Training on COVID-19, especially on infection prevention and control (IPC), should be mandatory for all staff and implementation of IPC practices should be monitored closely.
- Consideration should be given to weekly PCR testing of all frontline staff.
- Netcare said it welcomed the report and its recommendations.
News date: 2020-05-20
KRISP has been created by the coordinated effort of the University of KwaZulu-Natal (UKZN), the Technology Innovation Agency (TIA) and the South African Medical Research Countil (SAMRC).