A new analysis of pharmaceutical sales data from 67 countries indicates that antibiotic consumption has risen by more than 20% globally since 2016 but would likely have been much higher had the COVID-19 pandemic not occurred.
The study, published yesterday in the Proceedings of the National Academy of Sciences by researchers with One Health Trust, found that total antibiotic consumption for countries with available data rose 29.5 to 34.3 billion defined daily doses (DDD) from 2016 to 2023 (a 16.3% increase) and the overall consumption rate rose 10.6%. When the researchers extrapolated antibiotic use for countries that didn't provide data, they estimated a 20.9% increase in total antibiotic consumption and 13.1% increase in the consumption rate.
The increase was lower than the 35.5% increase the researchers found when they looked at global antibiotic consumption during the previous 7-year period (2008 through 2015). But that's because antibiotic consumption in the 67 countries with available pharmaceutical data, particularly the higher-income countries (HICs), saw significant declines in outpatient antibiotic use during the first year of the pandemic. Those declines have been attributed in part to masking, stay-at-home policies, and other SARS-CoV-2 reduction measures that may have reduced the transmission of respiratory pathogens that fuel outpatient antibiotic use.
The authors of the study say that while the impact of the pandemic makes it difficult to determine whether countries have had some success in efforts to reduce antibiotic use, post-pandemic increases in antibiotic consumption, particularly in developing nations, suggest more work is needed.
"The COVID-19 pandemic temporarily disrupted antibiotic use, but global consumption has rebounded quickly and continues to rise at an alarming rate," first author Eili Klein, PhD, a professor at Johns Hopkins University School of Medicine and a senior fellow at One Health Trust, said in a One Health Trust press release.
Antibiotic consumption varies by income level
The analysis, based on antibiotic sales data from the IQVIA MIDAS database, found that antibiotic consumption over the 8 years varied by countries' economic status. From 2016 through 2019, antibiotic consumption increased in the 28 lower-middle– and upper-middle–incomes countries (LMICs and UMICs) by 9.8% and decreased in the 39 HICs by 5.8%.
When the COVID-19 pandemic hit in 2020, antibiotic consumption fell across all 67 countries. But the decline was more pronounced in HICs, where antibiotic consumption fell by 17.8%, and it lasted longer in those countries. Starting in 2021, LMICs and UMICs saw sharp upticks in antibiotic consumption, while HICs saw only small increases.
"HICs experienced a 'delayed rebound' in antibiotic consumption following the pandemic, with a very small (0.8%) increase in consumption in 2021 followed by larger increases in 2022 and 2023," the study authors wrote. "While antibiotic consumption rates rose in 2023 in HICs, they had not quite returned to prepandemic levels by the end of 2023."
For the entire study period, the antibiotic consumption rate increased by 23.4% in UMICs and 14% in LMICs, while decreasing by 4.9% in HICs. The five regions with the largest increases in the antibiotic consumption rate over the study period all comprised UMICs and LMICs.
The COVID-19 pandemic temporarily disrupted antibiotic use, but global consumption has rebounded quickly and continues to rise at an alarming rate.
The researchers also found differences in the types of antibiotics consumed by countries at different income levels. Using the World Health Organization's Access, Watch, and Reserve (AWaRe) classification system, they noted that HICs consistently consumed more Access antibiotics, which include antibiotics that have a narrower spectrum of activity and are generally recommended for most empiric treatment.
On the other hand, UMICs and LMICs consumed more Watch antibiotics, which are broader spectrum drugs that have a higher potential for selection of antibiotic resistance and tend to be used in sicker patients. This could reflect a combination of two problems that have been well-documented in low-resource countries: limited access to certain antibiotics and higher rates of drug-resistant bacteria.
A concerning trajectory
Klein and his colleagues say the findings are in line with their previous research, which found that prepandemic increases in global antibiotic consumption were being driven by LMICs that were growing economically. That's because in many of these countries, despite limited access to some antibiotics, indiscriminate antibiotic use is a significant issue. The problem is exacerbated by weak healthcare systems and the spread of illnesses that are attributable to lack of clean water, sanitation, and hygiene.
The rapid increases in antibiotic consumption observed in lower-resources countries post-pandemic suggests those countries will continue to drive global antibiotic consumption going forward. When the researchers projected out to 2030, with the assumption that future antibiotic consumption falls within current ranges and there are no policy changes, they estimated that global antibiotic consumption would rise by 52.3%.
Their hope is that documenting these trends could help LMIC and UMICs develop and implement context-specific antimicrobial stewardship programs (ASPs) and national action plans that increase antibiotic access, limit antibiotic misuse and overuse, combat antimicrobial resistance (AMR), and help countries meet sustainable development goals.
"As countries grow economically and attempt to break out of the poverty cycle, they may be at risk for inappropriate antibiotic use, which could drive AMR and threaten progress toward healthcare goals," they wrote. "Thus, increasing support for the development of national action plans and ASPs is necessary."
They add that improvements in sanitation and hygiene, along with increasing use of vaccines and point-of-care diagnostics, could also help reduce the need for antibiotics in these countries.
"Improving infrastructure and access to water, sanitation, and hygiene, particularly in rapidly developing nations, along with improved access to vaccination, should be an important pillar in the fight against AMR," they concluded.
