News Scan for Apr 09, 2020

News brief

WHO profiles recent Saudi MERS cases

In a snapshot of MERS-CoV cases in Saudi Arabia in February, the country reported 18 cases, 5 of them fatal, from 9 different cities, the World Health Organization (WHO) said yesterday.

Four of the patients had a history of contact with camels. None were healthcare workers, and none had any known contact with earlier MERS-CoV (Middle East respiratory syndrome coronavirus) patients. Seven patients were from Riyadh, and Hafr Albatin, Najran, and Eastern each had two cases. Five cities each had one case: Al-Jawf, Mecca, Hail, Taif, and Jeddah.

All were adults, ages 34 to 81 years old, and all but two were men. All but one had an underlying health condition.

The WHO said that, as of Feb 29, it has received 2,538 MERS-CoV illness reports since 2012, with at least 871 deaths. The vast majority have been in Saudi Arabia.
Apr 8 WHO MERS-CoV update

Flu vaccine protection against hospitalization low across 3 seasons

Flu vaccine was 31% effective among outpatients and 36% effective among inpatients during three recent flu seasons, according to a study led by researchers from the US Centers for Disease Control and Prevention published today in Clinical Infectious Diseases.

The investigators tested adults who had acute respiratory illness (ARI) for flu in two vaccine effectiveness (VE) networks at three sites from 2015 to 2018. They estimated VE using logistic regression, adjusting for site, age, sex, race and ethnicity, peak influenza activity, time to testing from emergence of symptoms, season (overall VE), and underlying conditions.

They found overall VE of 31% among 14,573 (4,144 flu-positive) outpatients (95% confidence interval [CI], 26% to 37%) and 36% among 6,769 (1,452 flu-positive) inpatients (95% CI, 27% to 44%).

VE against the 2009 H1N1 strain was 37% (95% CI, 25% to 47%) among outpatients and 53% (95% CI, 37% to 64%) among inpatients. VE against H3N2 was 19% (95% CI, 9% to 27%) among outpatients and 23% (95% CI, 8% to 35%) among inpatients. VE against B viruses was 46% (95% CI, 38% to 53%) among outpatients and 46% (95% CI, 31% to 58%) among inpatients. VE differences were not significant for any comparison across sites.

Hospitalized patients were older (median age, 62 vs. 49 years) and had more predisposing conditions (median, 4 vs. 1) than outpatients.

"Inpatients and outpatients with ARI represent distinct populations," the authors wrote. "Despite comparatively poor health status among inpatients, influenza vaccination was effective in preventing hospitalizations associated with influenza." Flu-related hospitalizations are associated with poor clinical outcomes, high costs, and heavy healthcare resource burdens.

The authors said that suboptimal VE in recent years and the perception that flu is a mild illness lead some people to decide against vaccination. "Establishing VE against hospitalized influenza is important for policymakers, and may influence peoples' decisions on whether to get vaccinated," they wrote.
Apr 9 Clin Infect Dis abstract

Stewardship / Resistance Scan for Apr 09, 2020

News brief

Study shows stewardship benefits of ID specialists

A retrospective study of Veterans Health Administration (VHA) hospitals found that the presence of an infectious diseases (ID) specialist may facilitate improvements in antibiotic prescribing, US researchers reported today in Clinical Infectious Diseases.

For the study, a team led by researchers from the Iowa City Veterans Affairs Health Care System evaluated antibiotic use among patients admitted to an acute-care bed at 122 VHA hospitals during 2016. They used data from a mandatory antibiotic stewardship survey completed by VHA hospitals to determine which hospitals had access to an ID-trained physician or pharmacist, and which had antibiotic stewardship programs.

They then compared antibiotic use among all patient admissions at ID sites with antibiotic use among patients at non-ID sites. Antibiotic use was quantified as days of therapy (DOT) per days-present, and was categorized based on National Healthcare Safety Network definitions.

Overall, 18 of the 122 hospitals (14.8%) lacked an on-site ID specialist. During 2016, there were 525,451 admissions at the ID hospitals and 23,007 admissions at the non-ID sites. In the adjusted analysis, which accounted for factors such as demographics, individual comorbidities, and severity of illness, the presence of an ID specialist was associated with lower use of broad-spectrum antibiotics (odds ratio [OR], 0.92; 95% confidence interval [CI], 0.85 to 0.99), higher narrow-spectrum beta-lactam use (OR, 1.43; 95% CI, 1.22 to 1.67), and lower total antibiotic use (OR, 0.92; 95% CI, 0.86 to 0.99).

"Core principles of antibiotic stewardship include selecting narrow-spectrum agents when feasible, using antibiotics only when necessary, and prescribing antibiotics for the shortest effective duration," the authors of the study write. "Based on our findings, it appears that at least some of these principles were more broadly applied to patients at hospitals with ID specialists."

The authors suggest that ID specialists may mediate changes in prescribing not only by recommending use of more narrow-spectrum agents and discontinuation of unnecessary antibiotic therapy, but also by enhancing institutional knowledge of appropriate prescribing and facilitating acquisition of stewardship resources.
Apr 9 Clin Infect Dis abstract

Antibiotics commonly prescribed for viruses in Scottish children

In another study today in Clinical Infectious Diseases, UK and Canadian investigators reported that nearly 14% of the antibiotics prescribed to Scottish children under the age of 5 from 2009 through 2017 were for illness caused by common viruses.

Using population registries, data on positive microbiology tests for viral pathogens, and details on community-dispensed prescriptions for antibiotics, the researchers set out to estimate the proportion of antibiotic prescriptions among children under 5 that were explained by virus circulation. Multiple respiratory pathogens were considered, including respiratory syncytial virus (RSV), influenza, human metapneumovirus (HMPV), rhinovirus, and human parainfluenza (HPIV) types 1 to 4.

Over the study period, 452,877 children received 6,066,492 antibiotic prescriptions, and 41,666 had positive viral respiratory tests before their fifth birthday. The overall antibiotic dispensing rate was 607.9 antibiotics per 1,000 child years.

Clear correlations in the patterns of antibiotic prescribing and circulating respiratory virus burden were observed. An estimated 6.9% of all antibiotics prescribed were for RSV, while 2.4% were attributable to influenza, 2.3% to HMPV, 1.5% to HPIV-1, and 0.6% to HPIV-3. A higher proportion of antibiotic prescriptions were attributed to these viruses among previously healthy children without high-risk conditions, compared with children with chronic conditions. Amoxicillin was the most commonly prescribed antibiotic, representing 61.9% of all antibiotics in the study.

The authors say that future vaccines, particularly an RSV vaccine, could substantially reduce antibiotic prescribing in children. "In the meantime, these results highlight critical targets for improving primary care practice and reducing unnecessary antibiotic use," they write.
Apr 9 Clin Infect Dis abstract

Data reveal resistance common in certain ocular pathogens

Antibiotic resistance and multidrug resistance is common in ocular staphylococcal isolates, particularly among older patients, according to a study today in JAMA Ophthalmology.

Using data from the ongoing Antibiotic Resistance Monitoring in Ocular Microorganisms (ARMOR) study, US researchers looked at clinically relevant isolates of Staphylococcus aureus, coagulase-negative staphylococci (CoNS), Streptococcus pneumoniae, Pseudomonas aeruginosa, and Haemophilus influenzae cultured from patients with ocular infections from January 2009 through December 2018. They assessed overall antibiotic resistance profiles, concurrent and multidrug resistance, and trends by age of patient and over time.

A total of 6,091 isolates from 6,091 patients were submitted from 88 US sites. Of these, 2,189 were S aureus, 1,765 were CoNS, 590 were S pneumoniae, 767 were P aeruginosa, and 780 were H influenzae. Overall, 765 S aureus (34.9%) and 871 CoNS (49.3%) isolates were methicillin resistant and more likely to be concurrently resistant to macrolides, fluoroquinolones, and aminoglycosides compared with methicillin-susceptible isolates (P < .001 for all). Multidrug resistance was also frequently observed among methicillin-resistant S aureus (577, 75.4%) and CoNS (642, 73.7%) isolates. Antibiotic resistance among S pneumoniae isolates was highest for azithromycin (214, 36.3%), whereas P aeruginosa and H influenzae isolates showed low resistance overall.

Small changes in antibiotic resistance were noted over time (less than 2.5% per year), with decreases in resistance to oxacillin/methicillin and other antibiotics among S aureus isolates, a decrease in ciprofloxacin resistance among CoNS, and an increase in tobramycin resistance among CoNS. Analysis of S aureus and CoNS isolates found an increase in antibiotic resistance with patient age.

The authors say the findings overall align with previous ARMOR reports and retrospective reviews of ocular isolates from US clinical centers.
Apr 9 JAMA Ophthalmol study