News Scan for Sep 08, 2022

News brief

New Omicron subvariant mutation tied to kids' neurologic complications

Researchers in Taiwan have discovered a new mutation in the SARS-CoV-2 Omicron BA.2.3.7 subvariant that they suggest may be responsible for severe neurologic complications observed in young children on the island. Their study was published yesterday in the International Journal of Infectious Diseases.

The team analyzed the medical records of five pediatric COVID-19 patients hospitalized with severe neurologic complications such as seizures, symptoms indicating involvement of the meningeal layer of the brain, and encephalopathy in May 2022, about a month after Omicron began circulating in Taiwan.

The patients were 1 to 5 years old and experienced neurologic symptoms within 1 or 2 days after the onset of respiratory symptoms and fever. All patients had elevated levels of several inflammatory biomarkers, but none of their cerebrospinal fluid samples tested positive for COVID-19.

Whole-genome sequencing revealed that all viruses were Omicron BA.2.3.7 and that they had a previously unidentified K97E mutation on the spike protein that differed from other BA.2.3.7 strains. Genome mapping of the mutation showed similar sequences in patients in Hong Kong, Japan, and the United States at roughly the same time.

One child died of acute cerebral edema, brainstem compression, and multi-organ failure. The other patients recovered fully and were released from the hospital after 4 to 9 days.

The authors said their findings suggest that the neurologic complications are related to mutation-triggered hyperimmune states rather than direct viral invasion of the central nervous system. They also noted that other mutations in the same area of the SARS-CoV-2 spike protein have been linked to immune evasion.

"The K97E mutation, which has not been observed in Taiwan previously, potentially explains the sudden increase in incidence of severe neurological symptoms in pediatric patients due to its possible effect on immune regulation," the researchers concluded.
Sep 7 Int J Infect Dis study


Flu continues drop in Southern Hemisphere

Flu activity declined further in the Southern Hemisphere and is low in most of the world, except for some tropical locations, the World Health Organization (WHO) said in its latest update, which covers roughly the middle 2 weeks of August.

In Southern Asia, flu activity continues, with the 2009 H1N1 strain now dominant, especially in India. In Laos and Thailand, flu activity increased, and in East Asia, levels increased in northern China, mainly led by the H3N2 strain. Western Africa also reported a slight increase.

Of respiratory samples that were positive for flu at national flu labs in the middle part of August, influenza A made up 95.3% of samples. And, of subtyped influenza A viruses, 90% were H3N2.
Sep 5 WHO global flu update


Avian flu hits Minnesota poultry as H5N1 confirmed in Florida dolphin

Minnesota reported another highly pathogenic avian flu outbreak at a commercial poultry farm, and a handful of states reported more H5N1 detections in wild birds, according to updates from the US Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS).

In Minnesota, which recently reported an uptick in poultry outbreaks, the virus struck a turkey farm housing 50,000 birds in Morrison County in the central part of the state.

Also, the USDA reported 51 more H5N1 detections in wild birds, raising the total to 2,240. Most of the new detections involved waterfowl found dead, mostly from Utah's Box Elder and Davis counties. A new detections were also reported from New York and Oregon.
USDA APHIS poultry outbreak updates
USDA APHIS wild bird outbreak updates

In other avian flu developments, scientists at the University of Florida have reported H5N1 for the first time in an American dolphin. Swedish officials recently reported the virus in a porpoise, the first report of a detection in a cetacean.

In a statement, University of Florida Health said the virus was found in a young male dolphin found dead in March in Dixie County's Horseshoe Beach. The veterinary team initially did not suspect anything unusual when they performed the necropsy, but tests for common causes of deaths in dolphins were negative.

The animal had inflammation in and around the brain, and brain and lung samples were sent for further testing to Bronson Animal Disease Diagnostic Laboratory in Kissimmee, Florida, which identified avian flu. The National Veterinary Diagnostic Laboratory in Ames, Iowa, confirmed the strain as H5N1.
Sep 7 University of Florida Health statement

Stewardship / Resistance Scan for Sep 08, 2022

News brief

Quality improvement linked to better antibiotics for kids' skin infections

A quality-improvement (QI) program implemented at a children's healthcare system in Georgia was associated with improved antibiotic selection and duration for children with skin infections, researchers reported today in Pediatrics.

The QI program, implemented in three emergency departments (EDs) and eight urgent care centers (UCs) within Children's Healthcare of Atlanta, aimed to optimize outpatient antibiotic selection and duration for uncomplicated skin/soft tissue infections (SSTIs). Optimal treatment was defined as 5 days of cephalexin for nonpurulent (not containing pus) SSTIs and 7 days of clindamycin or trimethoprim/sulfamethoxazole for purulent SSTIs.

Interventions included revised SSTI treatment guidelines, provider education, a discharge order set, and participation in a maintenance of certification (MOC) QI project that involved education sessions, monthly group feedback, and individual scorecards. The MOC QI project included 50 ED and UC physicians (27% of eligible physicians).

To evaluate the success of the program, researchers compared antibiotic prescribing data for SSTIs during the baseline period (January 2018 to June 2019) and the postintervention phase (July 2019 to March 2021).

A total of 9,306 SSTIs were included, with 5,507 ED visits (59.2%) and 3,799 UC visits (40.8%). For all providers (MOC and non-MOC participants), optimal antibiotic choice plus duration for purulent SSTIs increased from 28% at baseline to 64%. For nonpurulent SSTIs, optimal antibiotic choice plus duration increased from 2% to 43%.

MOC participants had a similar baseline performance but showed greater improvement in optimal antibiotic prescribing for purulent (84%) and nonpurulent SSTIs (68%). Return visits requiring escalation of care did not significantly change pre- to post-intervention.

The study authors suggest the greater improvement among MOC participants may have been driven by monthly scorecards with individual performance.

"Although other QI projects have focused on inpatient management of SSTIs, this multisetting QI project focused on evidence-based outpatient antibiotic prescribing for pediatric SSTIs," the study authors wrote. "Our results could be readily generalized to other large, tertiary pediatric care centers looking to implement QI initiatives surrounding outpatient antibiotic stewardship."
Sep 8 Pediatrics abstract


Multidrug-resistant Shigella outbreak in Spain tied to cases in Belgium, UK

A study published this week in JAC-Antimicrobial Resistance confirms that a strain of multidrug-resistant (MDR) Shigella sonnei found in men who have sex with men (MSM) in Spain is similar to strains found elsewhere in Europe.

In the study, researchers from Seville, Spain, conducted genomic and molecular analysis of isolates from seven patients with shigellosis caused by MDR S sonnei that had similar epidemiologic characteristics. The cases were reported at a university hospital in Seville from October to December 2021, and of the six patients who reported sexual history, four identified as MSM.

All isolates showed resistance to penicillins, cephalosporins, fluoroquinolones, cotrimoxazole, and azithromycin, and whole-genome sequencing identified several resistance determinants, including azithromycin resistance genes and the blaCTX-M-27 gene, which carries an extended-spectrum beta-lactamase (ESBL) enzyme.

Further analysis found that all of isolates belonged to the same outbreak strain and were closely related to isolates from recent outbreaks of extensively drug-resistant (XDR) S sonnei in MSM in Belgium and the United Kingdom.

"Our results suggest that we are dealing with a high-risk clone of S. sonnei in continuous evolution," the study authors wrote. "The differences in terms of plasmid structures as well as the number of plasmids harboured by the seven S. sonnei isolates seems to indicate that this outbreak was produced by the transmission of one clone that is able to evolve and disseminate rapidly."

A report in February from the European Centre for Disease Prevention and Control noted an increase in XDR S sonnei infections in the United Kingdom and elsewhere in Europe and warned that the risk of spread among networks of MSM who engage in high-risk sexual practices, such as oral-anal contact, could be high in the coming months.

The authors say tracking the spread of successful epidemic clones of MDR S sonnei and understanding their evolution will be important for monitoring and control of outbreaks.
Sep 5 JAC-Antimicrob Resist study

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