June 25, 2020, 03:07 pm News Staff – Although it's well known that influenza vaccination confers protection against the flu, many people don't realize just how effective vaccination is. In fact, according to CDC data, influenza vaccination prevented roughly 4.4 million cases of influenza, 2.3 million influenza-related visits to family physicians and other primary care clinicians, and 58,000 hospitalizations during the 2018-2019 flu season alone.
Despite the fact that antibiotics are ineffective against viral infections such as influenza, evidence indicates that antibiotic prescribing peaks in the winter months during which influenza flourishes. Some researchers contend that this results from a combination of appropriate prescribing for bacterial respiratory infections secondary to flu and inappropriate prescribing practices. Because the influenza vaccine reduces flu case counts, it has been speculated that increasing vaccination coverage could reduce inappropriate use of antibiotics and slow the spread of antimicrobial resistance.
To gauge the validity of any association between influenza vaccine uptake and antibiotic prescription rates, researchers conducted a retrospective observational study using a combination of patient and prescribing data. The study results, published online June 6 in Open Forum Infectious Diseases, showed that an increase in influenza vaccination rates at the population level was associated with a corresponding decrease in antibiotic use at the state level.
The researchers obtained state-level monthly data on antibiotic prescriptions dispensed by retail pharmacies in the United States from 2009 to 2017 from the IQVIA Xponent database. They also retrieved state-level monthly vaccination coverage rates for the 2009-2010 through 2016-2017 influenza seasons from the CDC's FluVaxView database. Vaccination and prescription information collected covered pediatric, adult and elderly patient populations.
After controlling for various socioeconomic and structural factors that affect antibiotic prescription rates, the study authors found "a significant negative association" between increased influenza vaccination coverage and antibiotic prescription rates. Across all age groups, a 10% increase in the influenza vaccination rate was associated with a 6.5% reduction in prescription rates, which corresponded to a decrease of 14.2 antibiotic prescriptions per 1,000 people after controlling for covariates.
In terms of specific antibiotics, influenza vaccination coverage was inversely correlated with prescriptions for macrolides, tetracyclines, narrow-spectrum penicillins and aminoglycosides across all age groups. In infants, children and adolescents 18 and younger, there was a significant association between higher influenza vaccination rates and prescription reductions in all classes of antibiotics except broad-spectrum penicillins and fluoroquinolones.
The researchers noted that their analysis was limited by a number of factors, including the lack of more granular data on influenza vaccination coverage and acknowledgement that both vaccine and antibiotic use are driven by incalculable considerations such as patients' personal beliefs. Yet despite these limitations, the authors posited that improving influenza vaccine uptake could reduce overall antibiotic use.
"Our analysis suggests that increasing rates of influenza vaccination coverage may be effective in reducing antibiotic consumption in the United States through reduction of influenza prevalence and limiting secondary bacterial diseases," the authors concluded. "Substantially boosting seasonal influenza vaccination coverage should be a central element of efforts to reduce use of antibiotics."
These findings take on even greater significance in light of results from a second investigation that examined primary care physicians' knowledge of antibiotic resistance patterns and attitudes about judicious stewardship of these drugs.
In an article published June 20 in the same journal, researchers reported on the results of a national survey of primary care physicians regarding antibiotic resistance, antibiotic use and the need for stewardship.
The survey population consisted of 1,550 family physicians (43%), internists (35%) and pediatricians (22%). Most participants were male (58%), were between ages 45 and 64 (61%), worked primarily in a group practice (72%), ran a private physician-owned practice (55%), and had been in practice for at least 10 years (54%).
Analysis of their responses showed that although most PCPs expressed general concern about antibiotic resistance and inappropriate prescribing, far fewer of these clinicians acknowledged that these problems plagued their own practices.
Antibiotic resistance. Overall, 94% of participants agreed that antibiotic resistance was a problem in the United States. However, only 55% said that resistance was a problem in their own practices.
Similarly, 93% of participants agreed that inappropriate outpatient prescribing accelerated the emergence of antibiotic-resistant bacteria, and 91% acknowledged that inappropriate outpatient prescribing was a problem in the United States, but only 37% admitted that inappropriate prescribing was a problem within their own practice. In fact, 60% of respondents stated that they prescribed antibiotics more appropriately than their peers.
Many respondents said they felt pressured to prescribe antibiotics. Eighty-four percent of participants reported experiencing moderate, high or very high pressure to prescribe antibiotics.
Antibiotic stewardship. Overall, 72% of respondents thought antibiotic stewardship programs were needed to address the threat of antibiotic resistance, and 91% said stewardship programs were appropriate for office-based medical practices.
Many participants thought that stewardship programs should focus on patients and families, with 79% agreeing that such efforts would only be effective if they were paired with education for patients and parents.
Regarding the feasibility of implementing stewardship programs, half of participants agreed that tracking appropriate antibiotic use would be difficult to accomplish, and 47% felt they would need a lot of help to implement stewardship efforts within their practices.
When asked about ways to incentivize antibiotic stewardship and increase adoption, most participants suggested having their state health department publish reports on local antibiotic resistance patterns, followed by the creation of a standalone quality incentive program on antibiotic stewardship.
The study authors noted that the survey findings were consistent with previous research in that clinicians recognized antibiotic resistance and inappropriate prescribing as important issues on a national level but were less likely to perceive them as problematic within their own practices.
The authors also cited a 2019 CDC report that indicated significant progress has been made in implementing antibiotic stewardship programs in hospitals but warned of rising numbers of antibiotic-resistant infections in the community setting. Addressing that shortfall, they stated, will require collaborative efforts to support antibiotic stewardship and ensure the issue becomes a priority.
Finally, the authors recognized the role the ongoing coronavirus pandemic may play in boosting antibiotic prescription rates and hindering stewardship practices. "Given the potential impact of COVID-19 on antibiotic prescribing, these efforts are even more critical for ensuring recent progress is not lost and driving improved prescribing moving forward," they wrote.