Table 2.

Tiers of enhanced laboratory surveillance for coronavirus disease 2019 (COVID-19) in both inpatients and outpatients in Hong Kong^*

Tier	Inclusion criteria	Type of specimen collection	Patient placement and use of personal protective equipment
In-patients
1	Patient with clinical criteria (fever or acute respiratory illness or pneumonia) AND with epidemiological criteria (with travel history to a place with active community transmission of COVID-19 or had close contact with a confirmed case of COVID-19) within 14 days before onset of symptoms	Nasopharyngeal flocked swab (NPFS), or nasopharyngeal aspirate (NPA) [in viral transport medium (VTM)]	AIIR (single room) N95 respirator, eye protection by goggles or face shield, gloves, and isolation gown (AAMI level 1)†
2	Irrespective of history of travel, patient with pneumonia requiring ICU care; or occurring in clusters; or who is a health care worker.	NPFS, or NPA in VTM; lower respiratory tract such as sputum, tracheal aspirate (TA) (if intubated), and bronchoalveolar lavage (BAL) (if bronchoscopy)	AIIR (single room as far as possible); otherwise cohort nursing in AIIR
3	Any patient with pneumonia other than Tier 2	NPFS, or NPA in VTM; lower respiratory tract such as sputum, TA (if intubated), and BAL (if bronchoscopy)	Surveillance ward (one metre spacing between patients; increase air change per hour by mobile HEPA filter)
Outpatients in clinics and AEDs
4‡	Fever or respiratory symptoms subject to clinical assessment of physician in charge	Patients should be smart enough to understand the technique to collect “Deep Throat Saliva” in early morning for adult and pediatric cases	Hospitalization is not required; patients is called back for admission if the specimen is positive for SARS-CoV-2

Note. AAMI, Association for the Advancement of Medical Instrumentation PB70:2003 is to define the liquid barrier performance and classification of protective apparel and drapes intended for use in health care facilities (https://www.fda.gov/medical-devices/personal-protective-equipment-infection-control/medical-gowns); AED, accidental and emergency departments; AIIR, airborne infection isolation room; HEPA, high efficiency particulate air; ICU, intensive care unit.

^⁎The evolving criteria of active surveillance was reported.⁹

^†AAMI level 1 isolation gown is used when small amounts of fluid exposure is anticipated. AAMI level 3 isolation gown can be considered when splashing is anticipated. Alternatively, a waterproof apron on top of the AAMI level 1 isolation gown is also acceptable (with effect from February 19, 2020, day 51).

^‡The fourth tier enhanced laboratory surveillance was updated since February 20, 2020 (day 52).