Conceptualization, N.D.F. and A.L.; Methodology, N.D.F.; Validation, N.D.F. and A.M.; Formal Analysis, N.D.F.; Investigation, N.D.F. and A.L.; Writing—original draft preparation, N.D.F.; Writing—review and editing, N.D.F., A.M., N.T. and C.L.L.; Visualization, N.D.F. and C.L.L.; Supervision, C.L.L. All authors have read and agreed to the published version of the manuscript.

Figure 1. Inpatient antibiotic consumption at Vila Central Hospital, Vanuatu before and during COVID-19, 2018 to 2021: (a) Unadjusted model showing counterfactual; (b) Final model showing seasonal effects.

Figure 1. Inpatient antibiotic consumption at Vila Central Hospital, Vanuatu before and during COVID-19, 2018 to 2021: (a) Unadjusted model showing counterfactual; (b) Final model showing seasonal effects.

Figure 2. Outpatient antibiotic consumption at Vila Central Hospital, Vanuatu before and during COVID-19, 2018 to 2021: (a) Unadjusted model showing counterfactual; (b) Final model showing seasonal effects.

Figure 2. Outpatient antibiotic consumption at Vila Central Hospital, Vanuatu before and during COVID-19, 2018 to 2021: (a) Unadjusted model showing counterfactual; (b) Final model showing seasonal effects.

Table 1. Antibiotics for systemic use (J01) consumed by inpatients and outpatients at VCH, Vanuatu 2018 to 2021 with ATC code, route of administration, DDD units in grams obtained from the ATC/DDD index 2022 and Access, Watch and Reserve classification.

Table 1. Antibiotics for systemic use (J01) consumed by inpatients and outpatients at VCH, Vanuatu 2018 to 2021 with ATC code, route of administration, DDD units in grams obtained from the ATC/DDD index 2022 and Access, Watch and Reserve classification.

AntibioticClassATC CodeRouteDDD (g)AWaRe GroupAmoxicillinPenicillinsJ01CA040ral1.5AccessAmoxicillin ClavulanateBeta-lactam/beta-lactamase inhibitorJ01CR020ral0.625AccessAzithromycinMacrolidesJ01FA100ral0.3WatchCiprofloxacinFluoroquinolonesJ01MA020ral1WatchCloxacillinPenicillinsJ01CF020ral2AccessDoxycyclineTetracyclinesJ01AA020ral0.1AccessErythromycinMacrolidesJ01FA010ral1WatchMetronidazoleImidazoleJ01XD010ral1.5AccessPhenoxymethylpenicillinPenicillinsJ01CE020ral2AccessSulfamethoxazole/TrimethoprimSulphonamide/trimethoprimJ01EE010ral4Access

Table 2. Defined daily doses (DDDs) prescribed to inpatients and outpatients at Vila Central Hospital, Vanuatu before and during COVID-19: January 2018 to January 2020 and February 2020 and December 2021, respectively, with difference in mean monthly consumption before and during COVID-19.

Table 2. Defined daily doses (DDDs) prescribed to inpatients and outpatients at Vila Central Hospital, Vanuatu before and during COVID-19: January 2018 to January 2020 and February 2020 and December 2021, respectively, with difference in mean monthly consumption before and during COVID-19.

Antibiotic ConsumptionBefore the Pandemic
Jan 2018–Jan 2019During COVID-19
Feb 2020–Dec 2021 Inpatient oral antibiotic consumptionTotal DDDs15,66118,411Total DBDs226.97266.82Mean monthly DBDs9.0711.60Difference between mean monthly DBDs before and during COVID-192.66 p = 0.009 (95% CI 0.71; 4.61) Outpatient oral antibiotic consumptionTotal DDDs314,004295,508Total DIDs102.292.7Mean monthly DIDs4.094.03Difference between mean monthly DIDs before and during COVID-190.063 p = 0.74 (95% CI−0.33, 0.46)

Table 3. Antibiotics prescribed by type in defined daily doses (DDDs) by inpatients and outpatients at Vila Central Hospital, Vanuatu before and during COVID-19: January 2018 to January 2020 and February 2020 and December 2021, respectively, with percentage of total consumption and DDD unit of measurement.

Table 3. Antibiotics prescribed by type in defined daily doses (DDDs) by inpatients and outpatients at Vila Central Hospital, Vanuatu before and during COVID-19: January 2018 to January 2020 and February 2020 and December 2021, respectively, with percentage of total consumption and DDD unit of measurement.

Antibiotics Prescribed
(DDD Unit)Before the Pandemic: Jan 2019–Jan 2020During COVID-19:
Feb 2020–Dec 2021Inpatient DDDs/100 bed days (DBDs) (% total)Amoxicillin (1.5 g)46.2 (20.3)53.9 (20.2)Cloxacillin (2 g)84.6 (37.2)100.1 (37.5)Penicillin V (2 g)8 (3.5)16.8 (6.3)Amoxicillin/clavulanate (1.5 g)17.6 (7.7)23.8 (8.9)Azithromycin (0.3 g)2.9 (1.3)2.7 (1)Erythromycin (1 g)3.2 (1.4)2.8 (1)Ciprofloxacin (1 g)10.1 (4.4)10.3 (3.9)Doxycycline (0.1 g)5.2 (2.3)6.2 (2.3)Sulfamethoxazole/Trimethoprim (4 g)0.7 (0.3)1.1 (0.4)Metronidazole (1.5 g)48.5 (21.4)49.1 (18.4)Total DBDs per period226.9 (100)266.8 (100)Outpatient DDDs/1000 inhabitants/day (DIDs) (% total)Amoxicillin (1.5 g)43.1 (42.2)35.7 (38.5)Cloxacillin (2 g)14.1 (13.8)14.2 (15.3)Penicillin V (2 g)13.8 (13.5)15.9 (17.1)Amoxicillin/ clavulanate (1.5 g)6.7 (6.5)5.5 (5.5)Azithromycin (0.3 g)2.3 (2.3)2.4 (2.5)Erythromycin (1 g)1.02 (1.0)0.5 (0.6)Ciprofloxacin (1 g)3.4 (3.3)1.9 (2.1)Doxycycline (0.1 g)3.3 (3.2)2.9 (3.2)Sulfamethoxazole/Trimethoprim (4 g)2.3 (2.2)1.6 (1.7)Metronidazole (1.5 g)12.3 (12.1)12.12 (13.1)Total DIDs per period102.2 (100)92.7 (100)

Table 4. Antibiotic consumption by AWaRe classification for inpatients and outpatients at VCH, Vanuatu before and during COVID-19: January 2018 to January 2020 and February 2020 to December 2021, respectively, with percentage of total consumption according to AWaRe classification.

Table 4. Antibiotic consumption by AWaRe classification for inpatients and outpatients at VCH, Vanuatu before and during COVID-19: January 2018 to January 2020 and February 2020 to December 2021, respectively, with percentage of total consumption according to AWaRe classification.

Antibiotic Prescription by Access Watch and Restrict Class (AWaRe)AWaRe ClassificationBefore the Pandemic:
Jan 2019–Jan 2020During COVID-19:
Feb 2020–Dec 2021 Inpatient DDDs/100 bed days (DBDs) (% total)Watch class DBDs16.2 (7)15.8 (6)Difference between mean monthly Watch DBDs before and during COVID-190.041 p = 0.54 (95% CI−0.18; 0.09)Access class DBDs210.7 (93)251 (94)Difference between mean monthly DBDs before and during COVID-190.75 p = 0.49 (95% CI−2.93; 1.43) Outpatient DDDs/1000 inhabitants/day (DIDs)
(% total)Watch class DIDs6.9 (7)4.8 (5)Difference between mean monthly DIDs before and during COVID-190.066 p = 0.002 (95% CI 0.03; 0.11)Access class DIDs95.5 (93)87.9 (95)Difference between mean monthly DIDs before and during COVID-190.008 p = 0.96 (95% CI−0.36; 0.38)