Stewardship / Resistance Scan for Aug 01, 2017

News brief

Doctors call for diagnostic stewardship to improve antibiotic use

A commentary yesterday in JAMA argues for diagnostic stewardship as an additional strategy to reduce inappropriate use of antibiotics.

While culture and non-culture–based diagnostic tests are necessary for helping establish the presence or absence of infection, the authors write, the process of ordering and interpreting those tests is complex. In addition, clinicians often order common tests for patients who aren't exhibiting symptoms specific for the disease process. For example, they order Clostridium difficile tests for patients who don't have diarrhea and urine cultures for patients without symptoms of urinary tract infection.

The authors argue that the problem with these tests, especially the increasingly sensitive molecular tests, is that they frequently produce false-positive results or fail to distinguish colonization from infection. The end result is overtreatment and inappropriate antibiotic use.

As a result, some hospitals have launched efforts to improve diagnostic stewardship by modifying the process of ordering, performing, and reporting diagnostic tests. Examples of diagnostic stewardship interventions include educational campaigns to teach clinicians appropriate indications and sampling for tests, removal of specific tests from electronic health records, and laboratory policies that include refusing to process specimens that are collected and handled inappropriately.

The authors go on to write that while the most beneficial form of diagnostic stewardship has not yet been defined, and thoughtful application of diagnostic stewardship principles should be applied to mitigate any potential unintended consequences and maintain clinician autonomy, implementing diagnostic stewardship can improve clinical care by reducing inappropriate testing, false-positive test results, and over-diagnosis. And they say that stewardship will be even more important with the expanding array of molecular diagnostic tests.
Jul 31 JAMA viewpoint

Commentary details success of antibiotic stewardship in Danish animals

Two Danish experts detailed the initiatives behind Denmark's successful antimicrobial stewardship efforts in food animals, highlighting a farmer overuse identification program, an antibiotic tax, and lab verification for antibiotic prescriptions as playing key roles.

Their analysis appeared yesterday in a National Academy of Medicine (NAM) commentary.

The two scientists noted that the use of antimicrobials in food-producing animals increased in Denmark from 2003 to 2009, partly as a result of more pigs in production. As a result of increased antimicrobial use, the Danish Veterinary and Food Administration established the "Yellow Card" intervention in 2011, designed to target pig farmers using high amounts of antimicrobials. It set national threshold limits for the use of antimicrobials in weaners, grower pigs, and adult pigs and could result in an injunction for farmers using too many drugs.

In addition, Danish officials adopted two measures in 2013: (1) a tax on antimicrobials that favored narrow-spectrum antimicrobials and vaccines compared with broad-spectrum compounds and (2) mandated annual lab verification of intestinal and respiratory infections for prescriptions written for group treatments.

"Together, these interventions, particularly those implemented [after] 2010, appear to have ended the otherwise increasing trend in antimicrobial usage observed since 1999," the authors wrote. "The antimicrobial resistance levels in Denmark continue to be lower than in most EU countries, which is most likely because of the detailed research and monitoring of antimicrobial use and resistance in food animals and in humans."
Jul 31 NAM commentary

US expert underscores vaccines as key element to fight drug resistance

Bruce Gellin, MD, MPH, former director of the US National Vaccine Program Office in the Department of Health and Human Services, in a commentary today underscored the important role that vaccines can play in combating antimicrobial resistance.

Writing for Stat, Gellin, now president of global immunization for the Sabin Vaccine Institute, outlined key steps to addressing the problem, such as developing new antibiotics and stewardship measures. He added, "Preventing infections in the first place will also reduce the need for antibiotics. That's where vaccines come in as an important part of the solution."

Gellin also noted, "In the context of the global trend in antibiotic resistance, we have been undervaluing all that vaccines offer to both individuals and communities."

He noted that vaccines help prevent the rise of antimicrobial resistance by preventing bacterial diseases such as pneumococcal infections, bacterial meningitis, and pneumonia, but their use against viral diseases can also reduce antibiotic use by preventing influenza and other viral infections that are often mistreated with antibiotics.
Aug 1 Stat commentary

News Scan for Aug 01, 2017

News brief

H5N8 strikes again in South Africa and Italy; H5N1 hits Inner Mongolia

The highly pathogenic avian influenza virus H5N8 has struck again in South Africa and Italy, while H5N1 has surfaced in China's Inner Mongolia province, according to reports from the World Organization for Animal Health (OIE) and press services.

In a report to the OIE, South African officials said H5N8 has hit two more poultry farms, raising the number of outbreaks since June to six. Both outbreaks occurred in the eastern province of Mpumalanga, with 137 cases among 735 birds of an unspecified species. The report said 86% of the birds on the two farms were lost through death, destruction, or slaughter.

A handful of African countries have been hit by the H5N8 virus, with South Africa the latest one. The outbreaks in South Africa and Zimbabwe will be the subject of a 3-day meeting, starting tomorrow, of the Southern Africa Development Community and the United Nations Food and Agriculture Organization, according to report today from The Insider, a Zimbabwe news service.

In Italy, H5N8 surfaced in the north-central province of Lombardia, hitting a layer farm with 123,463 birds, officials told the OIE yesterday. All the birds were infected, but only 2,537 died, the report said. Because of missing information, the proportion of birds lost has not yet been calculated.

Counting this one, Italian officials have filed 18 H5N8 outbreak reports since Jan 23 of this year.

Meanwhile, an H5N1 outbreak has sickened 35,000 chickens on a farm in Inner Mongolia, killing 15,000 of them, according to a Reuters report today. The event in Tongliao city has prompted the culling of 66,500 chickens, said the story, citing China's agriculture ministry as its source. The ministry said the outbreak is under control.
Jul 31 OIE South Africa report
Aug 1 The Insider story
Jul 31 OIE Italy report
Aug 1 Reuters story

Study: Common aerosol-generating activities may pose little infection risk

A number of common medical procedures thought to generate aerosols that could pose an infection risk to healthcare personnel (HCP) may actually cause little threat, according to a study in which air sampling was done before and after various procedures.

The report, published yesterday in Clinical Infectious Diseases, notes the concern that some infections usually spread by droplets or direct contact could also spread through aerosols during procedures such as intubation, cardiopulmonary resuscitation, and bronchoscopy. Such concerns increase during outbreaks of emerging infections like Ebola, SARS (severe acute respiratory syndrome), and pandemic influenza.

For most of the procedures of concern, "evidence for the generation of infectious aerosols is based mostly on case reports and anecdotal evidence rather than on epidemiological studies or environmental air sampling," the researchers said.

The team used five different instruments to measure aerosols during seven patient care activities: patient bathing, changing bed linens, pouring and flushing liquid waste, bronchoscopy, noninvasive ventilation, and nebulized medication administration (NMA). Most of the sampling involved patients on contact precautions for drug-resistant infections. Each procedure was sampled five times, and the sample solutions were cultured for bacteria.

The team found a significant increase in aerosol particle concentrations after only 2 of 35 sampling events: NMA and bronchoscopy with NMA. "Bronchoscopy without NMA and noninvasive ventilation did not generate significant aerosols," the report says.

As for the culturing results, 6 of 28 baseline samples (21.4%) and 14 of 50 procedure samples (28.0%) were positive. The report said "minimal viable bacteria" were found, and most were common environmental organisms.

Although more research is needed, the authors said, the findings suggest that some procedures regarded as aerosol-generating may pose little infection risk to HCP.
Jul 31 Clin Infect Dis abstract

Placental malaria infection risk may be greater with female fetuses

A study of several hundred pregnant women in Sudan suggests that the risk of placental malaria infection may be higher when the fetus is female, according to a recent report in PLoS One.

The authors wrote that recent studies have revealed differences between male and female fetuses in the risk of a number of adverse pregnancy outcomes, such as stillbirth, preeclampsia, and fetal growth restriction. They also noted that malaria during pregnancy is a major cause of maternal and perinatal adverse effects in Sudan. Thus they aimed to assess whether the risk of malaria infection varies with the sex of the fetus.

The study was a secondary analysis of data on a cohort of women in eastern Sudan who were examined for the prevalence of and risk factors for malaria during pregnancy. The cohort consisted of 339 women, who had a mean age of 25.8 years and a mean of 2.7 children. Of their newborn babies, 157 (46.3%) were male and 182 (53.7%) were female.

Placental histology revealed that 5 women (1.5%) had active malaria infection, 9 (2.7%) had active-chronic infection, and 103 (30.4%) had past chronic infection, while 222 (65.5%) had no infection. Statistical analysis showed no association between maternal age or parity and infection, but women who had female babies had an increased risk of infection: odds ratio (OR), 2.55; 95% confidence interval (CI), 1.57–4.13; P < 0.001. Also, women who had blood group O had an increased risk: OR, 1.95; 95% CI, 1.19–3.10; P = 0.007.

The authors concluded that fetal gender may be a novel risk factor for placental malaria.
Jul 28 PLoS One report

WHO reports another 33,000 cases of cholera in Yemen

The World Health Organization (WHO) yesterday said there were almost 33,000 new cholera cases in Yemen last week, cementing the current outbreak as one of the world's worst.

From Jul 23 to 29, officials reported 32,978 suspected cholera cases and 24 deaths. Since the beginning of the second wave of the current outbreak, which began at the end of April, there have been a total of 430,401 suspected cases and 1,903 deaths. The case-fatality rate is 0.4%.

Though the cases have been declining slightly in the last 6 weeks, 21 of the country's 23 governorates are reporting cholera activity. And the portion of children under the age of 5 is increasing; that age-group now represents 21% of newly suspected cases.
Jul 31 WHO bulletin