Stewardship / Resistance Scan for Jul 01, 2019

News brief

Multifaceted strategy helps improve primary care prescribing in Portugal

A multidisciplinary, multifaceted intervention aimed at targeting health professionals' and patients' attitudes regarding antibiotic use helped improve outpatient antibiotic prescribing at Portuguese primary care clinics, a team of Portuguese researchers reported yesterday in the Journal of Antimicrobial Chemotherapy.

In a cluster-randomized controlled trial conducted in the catchment area covered by Portugal's Central Regional Health Administration, researchers looked at the impact of a voluntary intervention that used a combination of learning methods, topics, and strategies designed to address previously identified gaps in knowledge and attitudes about antibiotic prescribing. The intervention, which was explained in a letter to all clinic directors of primary care facilities in the intervention group, included active outreach visits to clinicians and pharmacists and dissemination of educational materials (posters and flyers) to the general public.

The trial measured the impact of the intervention on a set of quality indicators that included relative ratios of prescription of penicillins sensitive to beta-lactamase, penicillin combinations including beta-lactamase inhibitors, third- and fourth-generation cephalosporins and fluoroquinolones, and the ratio of broad- to narrow-spectrum antibiotics.

The participation rate in the educational intervention was 64% (197/309 primary care offices) in a total of 25 counties. Statistically significant improvements were obtained in the relative prescription of penicillins sensitive to beta-lactamase (overall relative change of +896%) and penicillin combinations including b-lactamase inhibitors (−161%), as well as in the ratio of broad- to narrow-spectrum antibiotics (−200%). Statistically significant results were also obtained for third- and fourth-generation cephalosporins, though only in the first month after the start of the intervention. No statistically significant effect was found for the relative prescription of fluoroquinolones.

"Improving the quality indicators of antibiotic prescribing is one of the main challenges facing efforts to halt antibiotic misuse," the authors write. "This study shows that these indicators can be improved by addressing knowledge and behavioural aspects surrounding physicians' clinical practice."
Jun 30 J Antimicrob Chemother abstract

European study examines susceptibility trends in urinary pathogens

In another study yesterday in the Journal of Antimicrobial Chemotherapy, French and Swiss scientists reported that urinary isolates collected from 24 European hospitals from 2010 through 2016 showed increasing susceptibility to fluoroquinolones and decreasing susceptibility to third-generation cephalosporins.

The retrospective cross-sectional study, conducted in emergency departments (EDs) in Denmark, France, Italy, Germany, the Netherlands, Spain, and Switzerland, analyzed 88,242 urinary isolates for temporal antimicrobial susceptibility trends. Escherichia coli (67.6%), Klebsiella spp. (8.4%), and Enterococcus faecalis (4.5%) were the main bacteria identified. Susceptibility of all isolates to third-generation cephalosporins and fluoroquinolones was 83.6% and 77.6%, respectively, and was slightly higher in E. coli. Susceptibility rates were highly variable across EDs.

Time-series analysis found a significant increase in susceptibility to fluoroquinolones and no significant trend for susceptibility to third-generation cephalosporins. But adjusting for patient age and sex, ED and organism, multivariate models showed that susceptibility to third-generation cephalosporins decreased from 2014 to 2016 (compared to 2010), while susceptibility to fluoroquinolones increased in 2015 and 2016.

Among isolates from 2016, multivariate models predicted high probability of susceptibility to fluoroquinolones in 11% of isolates (positive predictive value 91%) and a high probability of susceptibility to 3GCs in 35% of isolates (positive predictive value 94%). The authors say this finding is noteworthy because it suggests that the models could potentially be used to identify patients eligible for fluoroquinolone or third-generation cephalosporin treatment for pyelonephritis in EDs where susceptibility in the previous year was lower than 90%.

They note, however, that the ability of the models to guide empirical treatment of pyelonephritis in EDs still needs to be assessed.
Jun 30 J Antimicrob Chemother abstract

News Scan for Jul 01, 2019

News brief

New cases lift US measles total to 1,095

With 18 more infections recorded in the last week, the United States has seen 1,095 measles cases in 2019—the most cases in the United States since 1992 and since measles was declared eliminated in 2000.

Twenty-eight states have reported cases in 2019, a number unchanged for the past several weeks, according to a Centers for Disease Control and Prevention (CDC) update today. The CDC is tracking four ongoing outbreaks (3 or more related cases) in New York's Rockland County; New York City; Butte County, California; and Washington state.

"These outbreaks are linked to travelers who brought measles back from other countries such as Israel, Ukraine, and the Philippines, where large measles outbreaks are occurring," the CDC said.

As of Jun 24, New York City has noted 609 cases—13 more than the previous week—in a measles outbreak that began last September in predominantly Orthodox Jewish communities in Brooklyn and Queens.
Jul 1 CDC update
Jun 24 NYC Health update

CDC announces multistate Salmonella outbreak tied to papayas

Late last week the CDC announced a multistate outbreak of Salmonella Uganda infections linked to whole papayas imported from Mexico. The fresh fruit was sold in Connecticut, Massachusetts, New Jersey, New York, Pennsylvania, and Rhode Island.

A total of 62 people in eight states have become sickened after eating the fresh fruit. Twenty-three people have been hospitalized, but there have been no deaths. Illnesses began from Jan 14 to Jun 8, with a ramp-up seen since April. Of 21 people who were interviewed, the CDC said, 16 (76%) reported eating papayas before symptom onset.

New York state has the most cases, with 24, followed by Connecticut (14), New Jersey (12), Massachusetts (5), and Pennsylvania (4). Florida, Rhode Island, and Texas each have reported 1 case.

"Consumers in Connecticut, Massachusetts, New Jersey, New York, Pennsylvania, and Rhode Island who have whole, fresh papayas imported from Mexico in their homes should not eat them," the CDC warned. "Throw the papayas away, even if some of them were eaten and no one has gotten sick."

In 2017, the CDC tracked another Salmonella outbreak tied to Mexican papayas, which resulted in at least 251 illnesses in 25 states and 2 deaths.
Jun 28 CDC announcement
Nov 6, 2017, CIDRAP news scan

Airborne norovirus may be a factor in outbreaks, study suggests

Contact with infected persons and contaminated environments is thought to be the main pathway for transmitting norovirus particles, but a new study involving air sampling near infected patients suggests that the virus may be capable of spreading through the air as well.

Researchers from Lund University in Sweden, writing in Clinical Infectious Diseases, said a few studies have noted norovirus outbreaks in which air was considered the most likely route of infection, and two studies noted evidence of the virus in hospital air during outbreaks. But these studied did not shed any light on the sources of the virus.

The authors sampled the air near 26 patients infected with norovirus and used reverse-transcription polymerase chain reaction to analyze the samples for norovirus RNA. Samples were collected in corridors just outside patient rooms, inside the rooms, and in bathrooms. Air samples from other wards in the same hospitals were used as controls.

The analysis detected norovirus RNA in 21 (24%) of 86 air samples from 10 patients. All the positive samples were collected during or just before outbreaks (meaning infections in two or more patients). The authors found a strong temporal association between vomiting episodes and airborne norovirus RNA: samples collected within 3 hours after an episode were 8.1 times as likely to be positive as those collected at other times (P = .04).

The authors also found that the concentration of virus particles ranged from 5 to 215 per cubic meter of air and that detectable amounts of norovirus RNA were present in particles ranging from less than 0.95 microns to more than 4.51 microns in size. That size range means the particles can stay airborne for a long time and be easily inhaled, they said.

"The results suggest that recent vomiting is the major source of airborne norovirus and imply a connection between airborne norovirus and outbreaks," the researchers concluded. "The presence of norovirus RNA in submicrometre particles indicates that airborne transmission can be an important transmission route."
Jun 29 Clin Infect Dis abstract