News Scan for Jun 13, 2018

News brief

Idaho announces first plague case since 1992

A child from Elmore County, Idaho, is recovering from plague, the first human case confirmed in that state since 1992.

The Idaho Department of Health and Welfare (IDHW) said yesterday it is not known if the child contracted plague in Idaho or during a recent visit to Oregon. Both states have reported plague in wildlife.

"The case serves as a reminder to recreationists in southern Idaho that plague is dangerous to people and pets, but with proper awareness, precautions, and prompt treatment when needed, plague should not discourage you from enjoying the Idaho outdoors," the IDHW said. Idaho state officials last confirmed plague in ground squirrels in the desert south of Interstate 84 in Ada County in 2015 and 2016.

Squirrels and other rodents can carry plague, which is often transmitted to humans via flea bites. Humans can also contract Yersinia pestis, the bacterium that causes plague, after contact with an infected animal. In humans, plague can bring on a sudden onset of flu-like symptoms and painful swelling of the lymph nodes.

The new case is Idaho's sixth since 1940.
Jun 12 IDHW blog post

Study: Quick use of Tamiflu lowers odds of secondary infections

A new retrospective cohort study conducted in long-term care facilities (LTCFs) in Manitoba suggests that using oseltamivir (Tamiflu) as soon as possible after the start of an H3N2 flu outbreak can help reduce the risk of secondary infections.

The study was conducted during the 2014-15 flu season, during which there were 94 H3N2 outbreaks in Manitoba's LTCFs. Fifty-three outbreaks were included in the study.

In Manitoba, the standard protocol for an influenza outbreak in an LTCF is a 5-day course of oseltamivir at the therapeutic dose for symptomatic patients, with all other residents receiving 10 days of oseltamivir at a prophylactic dose. Researchers measured how many days passed between the start of the outbreak and the beginning of oseltamivir chemoprophylaxis.

Researchers found that for every day that passed from the start of an H3N2 flu outbreak to the initiation of oseltamivir in non-symptomatic residents, the odds of an at-risk resident developing a symptomatic infection increased by 33% (adjusted odds ratio, 1.3; 95% confidence interval, 1.21–1.5).

"This study provides strong evidence supporting the rapid detection of influenza A H3N2 outbreaks and the rapid administration of oseltamivir chemoprophylaxis in a LTC resident population," the authors concluded.
Jun 12 Infect Control Hosp Epidemiol study

Non-medical vaccine exemptions rising in states that allow them

Eighteen states allow non-medical exemptions (NMEs) from childhood vaccines, and a study published yesterday in PLoS Medicine shows that NMEs correlate with decreasing childhood vaccine uptake in certain cities and communities.

Researchers from Baylor College analyzed NME from the 2009-10 school year through 2016-17. In general, the number of NMEs increased from 2009 to 2014. Idaho had the highest NME rates in the country, with a handful of counties around or above a 20% exemption level.

Though most of the communities with high rates of NMEs were rural and home to fewer than 50,000 people, the researchers identified several major metropolitan areas with high NME status, including Phoenix, Salt Lake City, and Houston.

"The high numbers of NMEs in these densely populated urban centers suggest that outbreaks of vaccine-preventable diseases could either originate from or spread rapidly throughout these populations of unimmunized, unprotected children," the authors write.

The authors also included in their analysis a comparison between measles, mumps, rubella (MMR) vaccine rates and NMEs, showing an inverse association between NME rate and MMR vaccine coverage of kindergarteners (P = 0.03 by Spearman correlation).
Jun 12 PLoS Med study

Stewardship / Resistance Scan for Jun 13, 2018

News brief

Study links lower hospital antibiotic use with ASP components

An observational study of Canadian hospitals found that certain structural and strategic components of antimicrobial stewardship programs (ASPs) are associated with lower antibiotic use, a team of Canadian researchers reported yesterday in Infection Control and Hospital Epidemiology.

The study used a survey and data on antibiotic use to determine the relationship between ASP components and antibiotic use. The Ontario ASP Landscape Survey, developed by Public Health Ontario and sent to hospitals across the country, asked the clinicians most responsible for stewardship at their institution about eight structural and 32 strategic components of their ASP. Researchers used hospital purchasing data from 2014 to determine the crude and adjusted defined daily doses (DDD) of antibiotics per 1,000 patient-days across facilities. They then compared the rate ratios (RRs) of DDD per 1,000 patient-days for hospitals with and without each ASP component of interest.

Of 127 eligible hospitals, 73 (57%) participated in the study. A sevenfold difference in antibiotic use across hospitals was observed, ranging from 253 to 1,872 DDD per 1,000 patient-days. After adjustment for hospital and patient characteristics, the only structural component associated with lower risk-adjusted antibiotic use was the presence of designated ASP funding or resources (adjusted RR 0.87).

Of the strategic components on the survey, only prospective audit and feedback (adjusted RR, 0.80) and intravenous-to-oral conversion policies (adjusted RR, 0.79) were associated with lower risk-adjusted antibiotic use. No association between the overall number of ASP components and antibiotic use was found.

The authors say the study offers important considerations for ASPs in hospital settings.
Jun 12 Infect Control Hosp Epidemiol study

'Stand-by' antibiotics encourage unwarranted use, study finds

Finnish researchers report that carriage of "stand-by" antibiotics for travelers' diarrhea (TD) encouraged less cautious use of antibiotics, according to a new study in Travel Medicine and Infectious Disease.

The researchers reviewed questionnaires and health diaries filled out by 316 Finnish volunteers who had traveled to subtropical locations and acquired TD on their trip. The questionnaires included 103 multiple-choice or open-ended questions, and the health diaries collected information on symptoms, severity of illness, duration of symptoms, and antibiotic use. Multivariable analysis was applied to identify factors associated with antibiotic use.

Of the 316 travelers, 53 (17%) were carrying stand-by antibiotics. Antibiotic use was more frequent in the stand-by antibiotic carriers (34%) than non-carriers (11%). While antibiotics were taken equally for severe and incapacitating TD, more stand-by antibiotic carriers resorted to medication for mild/moderate symptoms (38% vs. 4%) and non-incapacitating disease (29% vs. 5%). All travelers with stand-by antibiotics had been advised to use them only for TD symptoms they considered severe.

Multivariable analysis showed that antibiotic use was associated with stand-by antibiotic carriage (odds ratio [OR], 7.2), vomiting (OR, 3.5), incapacitating diarrhea (OR, 3.6), age (OR, 1.03), and healthcare visits for diarrhea (OR, 465.3). The rate of travelers' diarrhea–related healthcare did not differ significantly between stand-by antibiotic carriers and non-carriers (3.8% vs. 6.1%)

The authors say the results are significant because stand-by antibiotics have long been prescribed for travel, with the assumption that it would decrease the rate of seeking healthcare abroad. But carrying stand-by antibiotics did not appear to significantly discourage medical visits. In addition, stand-by antibiotic carriers were less cautious with their antibiotic use, using the drugs mainly in cases of non-severe and non-incapacitating diarrhea.

They conclude, "To cut back on unwarranted use of antibiotics for TD, new approaches need to be explored."
Jun 9 Travel Med Infect Dis abstract

Individualized risk assessment tied to lower antibiotic use

A single center study found that an individualized risk assessment strategy for multidrug-resistant (MDR) organisms that uses a clinical prediction score for pneumonia can decrease the use of broad-spectrum antibiotics without an increase in adverse outcomes, researchers reported in the Journal of Antimicrobial Chemotherapy.

Researchers at Mount Sinai West in New York City reviewed the records of 102 patients admitted for community-onset pneumonia before and after the implementation of a risk assessment program for MDR organisms that uses the drug resistance in pneumonia (DRIP) score. The primary aim was to identify the effects of this intervention on antibiotic days of therapy (DOT), and secondary outcomes included all-cause readmissions and time to clinical improvement.

The investigators found that the program was associated with a decrease in broad-spectrum antimicrobials for treating methicillin-related Staphylococcus aureus (MRSA) and for pseudomonads, without an increase in adverse outcomes. It was not, however, tied to significantly lower odds of readmission or time to clinical improvement.
Jun 11 J Antimicrob Chemother abstract

Requiring carbapenem justification may lower its use, study finds

A stewardship-targeted justification requirement for computerized physician order entry reduced days of carbapenem use by 34% in 23 hospitals, according to a new study in the Clinical Pharmacy Research Report.

Researchers with Sanford Medical Center in Fargo, N.D., measured carbapenem days of therapy (DOT) after the stewardship intervention was implemented in the 23 medical centers. The program required physicians to justify carbapenem use in the electronic health record. The team compared periods from Dec 1, 2015, to Mar 31, 2016, and from Dec 1, 2016, to Mar 31, 2017.

They found that carbapenem use dropped from 35.8 DOT per 1,000 patient-days to 23.7 DOT per 1,000 patient-days, a 33.8% reduction. Morbidity, mortality, and resistance rates remained unchanged.

The authors conclude, "This study suggests that a stewardship-targeted justification requirement in computerized physician order entry is an effective approach to reducing carbapenem utilization."
Jun 11 Clin Pharm Res Rep study