Stewardship / Resistance Scan for Jun 09, 2020

News brief

Mass distribution of azithromycin linked to resistant strep in Africa

The addition of the antibiotic azithromycin to seasonal malaria chemoprevention (SMC) was associated with an increase in azithromycin-resistant serotypes of Streptococcus pneumoniae in children in Burkina Faso, researchers reported yesterday in The American Journal of Tropical Medicine and Hygiene.

To better understand whether mass distribution of azithromycin was associated with the emergence of resistance in S pneumoniae, the researchers collected and analyzed nasopharyngeal samples from 400 children enrolled in a large trial investigating whether adding the antibiotic to SMC had an effect on child mortality and morbidity. In the trial, children 3 to 59 months received four courses a year of SMC and azithromycin or a placebo over a period of 3 years (2014 through 2016). The researchers analyzed the nasopharyngeal samples for S pneumoniae carriage before and after treatments in each year of the study, and conducted antibiotic susceptibility tests and serotyping on S pneumoniae isolates.

Of the 1,468 S pneumoniae isolates obtained, 698 randomly selected isolates were tested and serotyped. A total of 56 serotypes were detected by polymerase chain reaction, but serotypes 6A, 19A, 19F, 23F, and 35B persisted in all the pre- and post-treatment surveys, both in children who received azithromycin and in those who received placebo. An increase in azithromycin-resistant strains of S pneumoniae was observed in all these serotypes following exposure to the antibiotic.

"In conclusion, this study has shown that the increase in the resistance of nasopharyngeal isolates of S. pneumoniae noted following MDA [mass drug administration] with AZ [azithromycin] used in association with SMC was probably not associated with the emergence of a single resistant clone but due to the emergence of resistance in pneumococci belonging to several different serotypes," the authors of the study wrote.
Jun 8 Am J Trop Med Hygiene abstract

Study finds high rate of antibiotic prescribing for sinusitis

An analysis of antibiotic prescribing for acute sinusitis found that half of the patients visiting an integrated health system in Chicago for the disease met the criteria for antibiotics, but the actual prescribing rate was much higher, researchers from Northwestern University Feinberg School of Medicine reported yesterday in Clinical Infectious Diseases.

For the study, the researchers analyzed data on adult visits to Northwestern Medicine for acute sinusitis in 2017 and selected 500 distinct visits for manual chart review, looking for which patients received an antibiotic. To meet the criteria for antibiotics, patients had to have persistent, severe, or worsening symptoms—the clinical criteria defined by the Infectious Diseases Society of America for treatment of bacterial sinusitis.

Of the 500 visits, 425 met all the inclusion criteria, and 214 patients (50%) met the criteria for antibiotic prescribing, with the most common symptom criteria being persistent symptoms. Clinicians prescribed antibiotics for 205 (96%) of these patients, but they also prescribed antibiotics for 193 of the 211 patients (92%) who did not meet the criteria for antibiotics.

The most commonly prescribed antibiotics were amoxicillin-clavulanate (46% of prescriptions), azithromycin (20%), amoxicillin (12%), and cefdinir (6%). The median duration of treatment was 10 days. Guidelines recommend amoxicillin-clavulanate and amoxicillin as first-line antibiotics for acute sinusitis, and specifically recommend against macrolides and third-generation cephalosporins.

The authors of the study also noted that, because their assessment of guideline-concordant antibiotic-appropriateness was very forgiving, the proportion of patients who met the criteria "likely represents the upper bound of appropriateness."

"Ambulatory stewardship measures have generally addressed only antibiotic-inappropriate diagnoses, such as non-specific upper respiratory tract infections, or the requirement for streptococcal testing with a diagnosis of pharyngitis," the authors wrote. "To meaningfully reduce inappropriate antibiotic prescribing, future stewardship efforts should address the diagnosis of and appropriateness of antibiotic prescribing for sinusitis."
Jun 8 Clin Infect Dis abstract

News Scan for Jun 09, 2020

News brief

Most UK COVID-19 pregnancy cases involve minority women

Black or other ethnic minority women in the United Kingdom make up 56% of all documented hospitalized cases of COVID-19 in pregnancy, according to a new study published in The BMJ.

The study was based on routine data collected as part of the UK Obstetric Surveillance System (UKOSS) from Mar 1 through Apr 14, and researchers analyzed data on 427 pregnant women hospitalized for COVID-19. Fifty-six percent of the women were black or Asian, 70% were overweight or obese, and 40% were age 35 or older.

Though most women recovered completely, 41 needed respiratory support, and 5 died. Only 12 babies born to mothers with COVID-19 tested positive for the virus.

"In common with previous reports, most women admitted to hospital with SARS-CoV-2 infection in pregnancy were in the late second or third trimester, which replicates the pattern seen for other respiratory viruses with women in later pregnancy being more severely affected," the authors concluded. "This supports the current guidance for strict social distancing measures among pregnant women, particularly in their third trimester."

In an accompanying commentary, Marian Knight, DPhil, the lead author of the study, writes that, 11 years after the inception of UKOSS, the COVID-19 pandemic demonstrates its usefulness

"Our study clearly illustrates the benefits of thinking ahead, designing and setting up study infrastructure when threats are only hypothetical," the authors said. "If nothing else, the covid-19 pandemic has crystallised the need for reliable basic epidemiological information, and that this is equally important in pregnancy must be recognised."
Jun 8 BMJ study
Jun 8 BMJ commentary

Sequencing suggests separate introduction in new DRC Ebola outbreak

Genetic sequencing of the Ebola virus in the new Democratic Republic of the Congo (DRC) outbreak suggests that it isn't related to the large outbreak in the east of the country or to a small 2018 outbreak in the same area of Equateur province, the World Health Organization (WHO) said today in a statement.

Though an investigation into the source is still under way, the event likely reflects a new introduction from an animal source. Matshidiso Moeti, MBBS, director of the WHO's African regional office, said the findings from the National Institute of Biomedical Research (INRB) in Kinshasa aren't surprising, because the two outbreaks are located far apart, and there is a flight ban due to the COVID-19 pandemic.

"Ebola is endemic in animal reservoirs in the DRC, so it was expected that new cases would emerge," she said "While the new Ebola outbreak in Mbandaka represents a challenge, it's one we are ready to tackle. With each experience we respond faster and more effectively."

Twenty WHO staff are on the ground to support the health ministry and its partners, and more will arrive this week. So far, 2,200 vaccine doses have been delivered, and 600 people in have been vaccinated in Mbandaka and Wangata health zones.

So far, 12 illnesses have been reported, 9 confirmed and 3 listed as probable. Eight people have died from their infections. The 2018 outbreak in the same part of the northwestern DRC resulted 54 cases, 33 of them fatal.
Jun 9 WHO statement