Nurses (auxiliary nurses, enrolled nurses and professional nurses), medical doctors (interns, medical officers, registrars and consultants) and auxiliary/para-medical staff involved in the care of patients admitted for respiratory illnesses at Chris Hani Baragwanath Academic Hospital (CHBAH). This will include staff that have been assigned to work in:

Internal Medicine: Staff working in the Ambulatory and Emergency Department, staff in the "pneumonia-admission" ward (ward 24), and staff in the COVID-19 confirmed case wards.

Paediatrics: Staff involved in-hospital care of patients admitted to the dedicated "pneumonia ward" and COVID-19 cases wards.

Intensive Care Unit: All medical staff working in the intensive care unit.

Nursing and medical-doctor staff that are working in the neonatal high-care and intensive care unit; who are likely to be at lower risk from SARS-CoV-2 acquisition in the health-care facility compared to their peers listed in Group 1.

A third group, with a likely intermediate risk for hospital-facility based SARS-CoV-2 infection, are:

VIDA staff involved in sample collection related to COVID-19, and laboratory personnel that will be involved in sample collection at VIDA.

Nurses and medical doctors from the Obstetrics & Gynaecology.

In 2021 with an eminent 3rd wave spreading across the country an additional group will be included comprising of any person working at CHBAH even if not in direct contact with patients.

To determine the prevalence of symptomatic and asymptomatic PCR-confirmed SARS-CoV-2 infections among HCW using a systematic sampling strategy, coupled with investigation when clinically indicated.

To define the duration of "shedding" (using molecular based PCR methods) of SARS-CoV-2 in HCW who are identified to be infected with the virus.