At the outset of the COVID-19 pandemic, there was concern that COVID-19 would increase antibiotic use and compromise the progress of antimicrobial stewardship (AMS) initiatives. In contrast, marked reductions in antibiotic prescribing and dispensing have been reported in the United Kingdom[[1]] and United States of America.[[2]] New Zealand’s public health response to the pandemic resulted in the elimination of COVID-19 and large reductions in the circulation of many common respiratory viruses and some bacterial pathogens, such as S. pneumoniae.[[3,4]] We recently reported a large reduction in community antibiotic dispensing in New Zealand.[[5]]

To further understand this phenomenon, we looked for harm associated with this reduction in community antibiotic use, noting that previous research suggested that reductions in community antibiotic use might result in increased hospitalisations with pneumonia or peritonsillar abscess.[[6]] In New Zealand, when community antibiotic use fell by 36% during and after a national lockdown—which was likely due to reduced access to healthcare and less circulation of respiratory viruses—there was no evidence of increased hospitalisation due to pneumonia, peritonsillar abscess or rheumatic fever.[[5]]

The reports of reduced antibiotic use during COVID-19 have all compared recent population level rates with historical data. To further evaluate the hypothesis that community antibiotic dispensing during COVID-19 decreased significantly without evidence of severe harm, we used national data to examine rates of community antibiotic use and the incidence of pneumonia, peritonsillar abscess or rheumatic fever during a period when the intensity of non-pharmaceutical interventions (NPIs)[[7]] differed by geographic area, effectively splitting the New Zealand population into two groups: higher intensity NPIs in the greater Auckland region, where the outbreak was localised, and lower intensity NPIs in the rest of New Zealand.

The decrease in weekly community antibiotic dispensing rates in the greater Auckland region was larger than the decrease observed in the rest of New Zealand (Figure 1A). Despite the larger reduction in antibiotic dispensing in the greater Auckland region, the rates of hospitalisation for pneumonia, peritonsillar abscess or rheumatic fever (Figure 1B, C and D respectively) in the greater Auckland region were comparable with those in the rest of New Zealand.

Taken together, the observational evidence from the COVID-19 pandemic suggests that substantial reductions in community antibiotic dispensing in New Zealand did not result in increased severe morbidity due to infectious diseases. These data may help to convince clinicians and the public that a large proportion of outpatient antibiotic use in previous years has been unnecessary.

Figure 1: Percentage change in antibiotic dispensing rates (Figure 1A) and rates of hospital discharge with pneumonia (Figure 1B), peritonsillar abscess (Figure 1C) and acute rheumatic fever (Figure 1D) for the greater Auckland region (solid lines—estimated 2020 population 1.74 million people), where higher intensity non-pharmaceutical interventions (NPIs) were in place during calendar weeks 33–41, and for the rest of New Zealand (dashed lines—estimated 2020 population 3.34 million people), where lower intensity NPIs were in place during calendar weeks 33–41. Weekly antibiotic dispensing rates and hospital discharge rates, obtained from the National Pharmaceutical Collection and the National Minimum Database, are indexed to rates from 2017–2019 to account for baseline differences in the two regions.

At the outset of the COVID-19 pandemic, there was concern that COVID-19 would increase antibiotic use and compromise the progress of antimicrobial stewardship (AMS) initiatives. In contrast, marked reductions in antibiotic prescribing and dispensing have been reported in the United Kingdom[[1]] and United States of America.[[2]] New Zealand’s public health response to the pandemic resulted in the elimination of COVID-19 and large reductions in the circulation of many common respiratory viruses and some bacterial pathogens, such as S. pneumoniae.[[3,4]] We recently reported a large reduction in community antibiotic dispensing in New Zealand.[[5]]

To further understand this phenomenon, we looked for harm associated with this reduction in community antibiotic use, noting that previous research suggested that reductions in community antibiotic use might result in increased hospitalisations with pneumonia or peritonsillar abscess.[[6]] In New Zealand, when community antibiotic use fell by 36% during and after a national lockdown—which was likely due to reduced access to healthcare and less circulation of respiratory viruses—there was no evidence of increased hospitalisation due to pneumonia, peritonsillar abscess or rheumatic fever.[[5]]

The reports of reduced antibiotic use during COVID-19 have all compared recent population level rates with historical data. To further evaluate the hypothesis that community antibiotic dispensing during COVID-19 decreased significantly without evidence of severe harm, we used national data to examine rates of community antibiotic use and the incidence of pneumonia, peritonsillar abscess or rheumatic fever during a period when the intensity of non-pharmaceutical interventions (NPIs)[[7]] differed by geographic area, effectively splitting the New Zealand population into two groups: higher intensity NPIs in the greater Auckland region, where the outbreak was localised, and lower intensity NPIs in the rest of New Zealand.

The decrease in weekly community antibiotic dispensing rates in the greater Auckland region was larger than the decrease observed in the rest of New Zealand (Figure 1A). Despite the larger reduction in antibiotic dispensing in the greater Auckland region, the rates of hospitalisation for pneumonia, peritonsillar abscess or rheumatic fever (Figure 1B, C and D respectively) in the greater Auckland region were comparable with those in the rest of New Zealand.

Taken together, the observational evidence from the COVID-19 pandemic suggests that substantial reductions in community antibiotic dispensing in New Zealand did not result in increased severe morbidity due to infectious diseases. These data may help to convince clinicians and the public that a large proportion of outpatient antibiotic use in previous years has been unnecessary.

Figure 1: Percentage change in antibiotic dispensing rates (Figure 1A) and rates of hospital discharge with pneumonia (Figure 1B), peritonsillar abscess (Figure 1C) and acute rheumatic fever (Figure 1D) for the greater Auckland region (solid lines—estimated 2020 population 1.74 million people), where higher intensity non-pharmaceutical interventions (NPIs) were in place during calendar weeks 33–41, and for the rest of New Zealand (dashed lines—estimated 2020 population 3.34 million people), where lower intensity NPIs were in place during calendar weeks 33–41. Weekly antibiotic dispensing rates and hospital discharge rates, obtained from the National Pharmaceutical Collection and the National Minimum Database, are indexed to rates from 2017–2019 to account for baseline differences in the two regions.