Biosecurity advisers endorse tighter pathogen research reviews and recommendations

News brief

The National Science Advisory Board for Biosecurity (NSABB) on Jan 27 endorsed findings and recommendations from two of its working groups, one that focused on oversight of potential pandemic pathogens and the other that examined policies regarding dual-use research of concern (DURC).

DURC refers to experiments that can be used for good or ill.

The draft report was endorsed with minor modifications. The NSABB, made up of outside experts, advises the US Department of Health and Human Services and the National Institutes of Health (NIH) on policies related to federally funded research on potential pandemic pathogens. In February 2022, the government asked the NSABB to look at both issues, and on Jan 20, the two working groups delivered their draft findings and recommendations.

One of the key findings was that the definitions of potential pandemic pathogens and enhanced versions of them are too narrow, focusing too much on "highly transmissible" and "highly virulent." And the work group that looked at DURC said government policies have resulted in stronger oversight, but its framework applies only to a small fraction of life sciences research.

In a statement, NIH Director Lawrence Tabak, DDS, PhD, praised NSABB members for their thoughtful and careful consideration of the important policy issues and thanked scientists and the public for their input.

The NIH said federal officials will consider the report as part of its review of oversight frameworks for potential pandemic pathogen and DURC activities, after which it will announce the next steps in the review process.

Studies: COVID vaccine boosters lower risk of death in adults, ED visits in kids

News brief

Mary Van Beusekom, MS

COVID-19 vaccine boosters lower the risk of death among adults with multiple chronic conditions by more than 90% and increase protection against emergency department (ED) or urgent care (UC) visits among children aged 5 to 11 years by 77%, two new Omicron variant studies find.

In CMAJ, a team led by University of Hong Kong researchers compared the death rate among adults with at least two chronic conditions who received two or three Pfizer/BioNTech or Sinovac COVID-19 vaccine doses from November 2021 to March 2022.

The team followed 120,724 Pfizer recipients (including 87,289 booster recipients) for a median of 34 days and 127,318 Sinovac recipients (including 94,977 booster recipients) for a median of 38 days.

Among Pfizer recipients, booster recipients were 95% less likely to die of COVID-19 than two-dose recipients (5 vs 34 deaths; weighted incidence rate ratio [IRR], 0.05). Similarly, Sinovac booster recipients had a 92% lower risk of death than two-dose recipients (26 vs 88 deaths; weighted IRR, 0.08).

In a CMAJ news release, senior author Esther Chan, PhD, of the University of Hong Kong, said the results "support the effectiveness of booster doses of vaccines of 2 different technological platforms."

Third dose upped protection to 77%

In a study in the Journal of the Pediatric Infectious Diseases Society, a team led by Kaiser Permanente Southern California researchers estimated the protection of two or three doses of the Pfizer vaccine against Omicron-related ED and UC visits among children aged 5 to 11 years with respiratory infections from November 2021 to September 2022.

The 1,992 COVID-infected children were compared with 1,992 non-COVID controls using a test-negative design. Estimated effectiveness of two doses against ED or UC visits was 60% up to 3 months before waning to 28%; a booster increased protection to 77%.

"Despite protection against COVID-19 afforded by vaccination in children 5-11 years of age, vaccine uptake in this age group remains considerably lower than that observed in older populations," the authors wrote.

Report highlights the occurrence of beta-lactamase resistance genes in US hospitals

News brief

Chris Dall, MA

A 5-year study of data from US hospitals provides a national picture of the prevalence and trends in Escherichia coli and Klebsiella pneumoniae isolates carrying beta-lactamase antibiotic resistance genes, researchers reported last week in Open Forum Infectious Diseases.

In the study, researchers from JMI Laboratories in Iowa conducted antibiotic susceptibility testing on 19,453 E coli and K pneumoniae isolates collected from 56 US hospitals from 2016 through 2020. Isolates that displayed reduced susceptibility to at least two of four antibiotics (ceftazidime, ceftriaxone, aztreonam, or cefepime) or resistance to carbapenems were submitted for whole-genome sequencing for identification of extended-spectrum beta-lactamase (ESBL) genes and other beta-lactamase mechanisms, which confer resistance to beta-lactam antibiotics and make E coli and K pneumoniae infections more difficult to treat.

Overall, ESBL production was noted among 14.2% of the E coli isolates and 12.5% of the K pneumoniae isolates, which corresponded to 86.8% and 91.9% of the isolates resistant to cephalosporins and/or aztreonam without carbapenem resistance, respectively. The most common ESBL gene detected was bla_CTX-M-15, which accounted for 55% of ESBL producers. ESBL production was highest in Middle Atlantic states.

ESBL rates were stable over the study period, but a significant increase in ESBL-producing isolates from bloodstream infections was observed, and ESBL production significantly increased among K pneumoniae isolates as well, mainly driven by an increase in bla_CTX-M.

Carbapenem resistance and carbapenemase genes were noted in 166 and 145 isolates, respectively, and rates of carabapenem-resistant Enterobacterales (CRE) declined from 44 isolates in 2016 to 28 in 2020. Carabapenems and ceftazidime-avibactam were very active against ESBL producers without carbapenem resistance, while ceftazidime-avibactam was the most active agent against CRE isolates.

"This study reliably reports the occurrence of b-lactam-resistant phenotypes and genes in U.S. hospitals, providing a national picture of the distribution of isolates with these characteristics," the study authors wrote. "The activity of new and established antimicrobial agents is also reported and provides an understanding of resistance profiles."