Release date: 21 May 2021
The HKSAR Government attaches great importance to the threat of antimicrobial resistance (AMR). A High Level Steering Committee (HLSC) chaired by the Secretary for Food and Health has been established to formulate strategies and implement actions to combat AMR in Hong Kong, and the Hong Kong Strategy and Action Plan on Antimicrobial Resistance (2017- 2022) (Action Plan) was launched in July 2017.
The Action Plan sets out monitoring of antimicrobial usage as one of the strategic actions. Activity 3.2.1 of the Action Plan further suggested to collect the antimicrobial dispensing data from Hospital Authority (HA) to monitor antimicrobial usage in public hospitals and clinics. After studying the antimicrobial dispensing data of public hospitals and clinics of HA (including both non-inpatient and inpatient services), AMU surveillance reports were compiled and published at Centre for Health Protection website. This is the third report which provides a brief account of the surveillance findings for year 2019. Please click here to view further details.
Following the recommendation of WHO for AMU surveillance[1], the following core set of antimicrobials under WHO’s Anatomical Therapeutic Chemical (ATC) classification system (Year 2019) was adopted for surveillance purpose. Only antimicrobials given for systemic use[2] were included while topical antimicrobials were excluded.
| ATC Code | ATC Group/Subgroup |
| J01 | Antibacterials for systemic use |
| P01AB | Nitroimidazole derivatives, agents against amoebiasis and other protozoal diseases |
| A07AA | Antibiotics, intestinal antiinfectives |
Dispensing data for a total of 15 broad-spectrum antimicrobials identified by experts in HA (also known as ‘Big Guns’) were examined because of their importance on treating resistant infections.
The surveillance period for AMU is defined by calendar year. Results were analysed and presented as Defined Daily Dose (DDD)[3]. As some of the DDD constants were updated by WHO in 2019[4], the DDD figures of previous years have been re-calculated accordingly which would be different from the figures presented in the past reports. Results were also presented as DDD per 1,000 attendances and DDD per 1,000 patient-days of various specialties for both non-inpatient and inpatient services respectively.
Since the Action Plan was published in 2017, the situation of 2016 has been chosen as the baseline for comparison.
Following the European Centre for Disease Prevention and Control (ECDC), compound annual growth rate (CAGR) was adopted to illustrate average annual rate of change when comparing antimicrobials dispensed in 2019 with that in 2016.
CAGR = (SU2019 / SU2016)(1/3) - 1
In this equation, SU2019 and SU2016 refer to the total amount of antimicrobials dispensed for year 2019 and 2016 respectively.
Total antimicrobials dispensed in public hospitals and clinics
In 2019, the total antimicrobials dispensed for non-inpatient and inpatient services were 274.41 DDD/1,000 attendances and 906.10 DDD/1,000 patient-days respectively. When comparing with that of 2016, increases for both services were observed (by 8.14 DDD/1,000 attendances or CAGR of 1.01% for non-inpatient service; by 9.70 DDD/1,000 patient-days or CAGR of 0.36% for inpatient service).
Ten Most Dispensed Antimicrobials in Public Hospitals and Clinics
The ten most dispensed antimicrobials accounted for over 80% of all antimicrobials dispensed for HA services in 2019. Among them, amoxicillin/clavulanate topped the list since 2016, accounted for 44.68% of all antimicrobials dispensed in 2019 while doxycycline showed the largest increase in dispensing quantity from 2016 to 2019 (CAGR: 20.10%), followed by co-trimoxazole (CAGR: 12.97%). Cloxacillin showed the largest decrease in dispensing quantity from 2016 to 2019 (CAGR: -14.27%), followed by clarithromycin (CAGR: -4.42%).
Broad-spectrum antimicrobials (Big Guns) dispensed in public hospitals and clinics
Regarding the broad-spectrum antimicrobials, their dispensing quantities accounted for about 7.99% of total antimicrobials dispensed in HA in 2019. Majority of these broad-spectrum antimicrobials were dispensed in inpatient services and the most dispensed one from 2016 to 2019 was piperacillin/tazobactam, contributing about half (48.31%) of all broad-spectrum antimicrobials dispensed in 2019, followed by meropenem and then vancomycin.
From 2016 to 2019, the dispensing quantity of these antimicrobials has shown an increase in CAGR of 8.73%. Among them, ceftaroline fosamil and cefepime showed the largest increase (CAGR: 26.03% and 20.75% respectively).
Antimicrobials dispensed in HA by service
The overall dispensing quantity in HA non-inpatient service showed an increase in CAGR of 3.27% from 2016 to 2019 when considering those attendances with antimicrobial only. Among attendances with antimicrobials, dispensing quantity of ‘Specialist Out-patient (Clinical)’, ‘Primary Care (GOPC)’ and ‘Accident & Emergency’ showed increases in CAGR of 4.46%, 1.39% and 1.15% respectively.
Among the 10 most dispensed antimicrobials, amoxicillin/clavulanate has been the most dispensed antimicrobial since 2016 and it accounted for around 42% of the total antimicrobials dispensed in HA non-inpatient service.
Among all broad spectrum antimicrobials dispensed in HA, only 0.74% were dispensed in non-inpatient services in 2019 and no increase was observed from 2016 to 2019.
‘Intensive Care Unit / High Dependency Unit (ICU/HDU)’ dispensed the highest quantity of antimicrobials (1678.31 DDD/1,000 patient-days), followed by ‘Surgery’, ‘Medicine’, ‘Orthopaedics & Traumatology (O&T)’ and ‘Others’ (1261.29, 961.52, 800.37 and 631.31 DDD/1,000 patient-days) in 2019.
The total antimicrobials dispensed in HA inpatient service (DDD/1,000 patient-days) showed an increase in CAGR of 0.36% from 2016 to 2019. Specialties under ‘Others’ category showed the largest increase (1.96%), followed by ‘Surgery’ (1.11%), while ‘Orthopaedics & Traumatology’ showed the largest decrease (-2.29%) and followed by ‘Medicine’ (-0.31%) and then ‘ICU/HDU’ (-0.19%).
In 2019, ‘ICU/ HDU’ was the specialty with the largest quantity of broad-spectrum antimicrobials dispensed (530.14 DDD per 1,000 patient-days), followed by ‘Medicine’, ‘Surgery’, ‘O&T’ and ‘Others’ (150.86, 130.34, 70.97 and 59.82 DDD per 1,000 patient-days respectively).
For broad-spectrum antimicrobials dispensed, ‘Surgery’ had the largest increase in CAGR of 8.00%, followed by ‘Others’ (6.92%), ‘Orthopaedics & Traumatology’ (6.38%), and then ‘Medicine’ (5.03%) from 2016 to 2019. ‘ICU/HDU’ only increased by 0.33% in CAGR.
The key findings of 2019 surveillance include:
An increase in total antimicrobial dispensed necessitates to have Antibiotics Stewardship Programmes (ASP) in place to monitor and promote optimisation of antimicrobial usage at various levels.
Findings in relation to dispensing of doxycycline (sharpest increase among the 10 most commonly dispensed antimicrobials) and piperacillin/tazobactam (the most commonly dispensed broad-spectrum antimicrobial) warrant further exploration.
We would like to acknowledge stakeholders from HA such as Information Technology & Health Informatics Division, Quality and Safety Division, Strategy and Planning Division, Chief Pharmacist’s Office, and various Working Groups for provision of input to facilitate compilation of the AMU surveillance findings for year 2019.
[1] https://apps.who.int/iris/rest/bitstreams/1313107/retrieve
[2] Only antimicrobials given by oral, parenteral, rectal and inhalation were included in the surveillance
[3] DDD is a standardised unit adopted by WHO to facilitate comparison of drug usage.
[4] For example, DDD constant for oral use of amoxicillin was changed from 1000mg in 2018 to 1500mg in 2019.