Stewardship / Resistance Scan for Jun 17, 2021

News brief

Korean study details risk factors for drug-resistant organisms in COVID patients

Multidrug-resistant organisms (MDROs) were isolated in more than a quarter of South Korean patients with confirmed COVID-19 pneumonia and microbial culture results, with corticosteroid use identified as a significant risk factor, researchers reported yesterday in the American Journal of Infection Control.

The researchers from Soonchunhyang University College of Medicine looked at data on patients hospitalized for COVID-19 pneumonia at 1o hospitals in South Korea from February 2020 through May 2020, analyzing microbial culture results and epidemiology and risk factors for isolation of MDROs. Of the 152 patients identified with COVID-19 pneumonia, 47 had microbial culture results.

MDROs were isolated from 28% of patients with culture data (13 of 47) and 8.6% of all patients with COVID-19 pneumonia (13 of 152). The most common MDRO isolated was Stenotrophomonas maltophilia (five isolates), followed by methicillin-resistant Staphylococcus aureus (four isolates). MDROs were most commonly isolated from sputum samples. In-hospital mortality was significantly higher in patients with MDRO isolation than those without (62% vs. 15%).

All patients with MDROs received previous antibiotics. Multivariable analysis indicated that systemic corticosteroid use after COVID-19 diagnosis (adjusted odds ratio [aOR], 15.07; 95% confidence interval [CI], 2.34 to 97.01) and long-term care facility (LTCF) stay before diagnosis of COVID-19 (aOR, 6.09; 95% CI, 1.02 to 36.49) were independent risk factors for MDRO isolation.

The study authors say that while previous LTCF stay is a well-known risk factor for MDRO colonization, the finding that corticosteroid use may promote MDRO infection has great implications, since corticosteroids have been widely used in hospitalized COVID-19 patients.

"Owing to the risk of MDRO infection, corticosteroid usage should be carefully considered only for patients with indication," they wrote.
Jun 16 Am J Infect Control study

Report finds increased use of critical class of antibiotic on UK pig farms

Previously unpublished data indicate use of certain medically important antibiotics more than doubled on United Kingdom pig farms from 2015 through 2019.

The data, compiled by the Agriculture and Horticulture Development Board (AHDB) and obtained under Freedom of Information laws by the Bureau of Investigative Journalism, Vet Record, and The Guardian, show that use of aminoglycosides in pigs jumped from 2.6 milligrams per kilogram of body weight in 2015 to 5.9 mg in 2019.

The news follows a report from AHDB last week showing that overall antibiotic use, along with use of highest-priority critically important antibiotics, on UK pig farms has declined significantly since 2015. Aminoglycosides are considered a critically important antibiotic by the World Health Organization.

Industry experts told the Bureau of Investigative Journalism that the increase in aminoglycoside use could be linked to the phasing out of other critically important antibiotics like colistin, and to preparations for a European Union ban on zinc oxide, which is used to treat post-weaning diarrhea in piglets. They also expressed concern that the ban could lead to a rise in antibiotic use on pig farms in the coming years.

"We do have great concern about losing zinc oxide because there's a chance it will increase our antibiotic use," a veterinarian with the Pig Health and Welfare Council told the Bureau.
Jun 17 Bureau of Investigative Journalism story
Jun 10 AHDB report

News Scan for Jun 17, 2021

News brief

Racial disparities are seen in COVID-19 deaths

Black COVID-19 patients were more likely to die or be discharged to hospice after 30 days of hospitalization compared with White patients, according to a study today in JAMA Network Open. The researchers add, though, that the largest factor was the overall mortality and hospice rates of the hospitals where patients were treated.

The researchers looked at 44,217 Medicare beneficiaries (median age, 76.3 years) across 1,188 US hospitals from Jan 1 to Sep 21, 2020. About three quarters (75.7%) of patients were White, and the remaining were Black. Overall, 12.9% of White patients died or were discharged to hospice compared with 13.5% of Black patients. While this crude comparison did not show any disparities, after the researchers adjusted for patient sociodemographics and clinical characteristics, they found that Black people were at 11% higher risk (95% confidence interval [CI], 1.03 to 1.19).

The data were also adjusted for which hospitals patients were admitted to, after which the odds ratio became statistically insignificant again (1.02; 95% CI, 0.94 to 1.10). The researchers ran an additional analysis that looked at US states rather than hospitals, the results of which indicated to them that some of the racial disparities stemmed from state-level rather than hospital-level factors.

"This should not be interpreted as evidence that there was no differential treatment of Black and White patients within individual hospitals, since the study was not designed to examine this," David W. Baker, MD, MPH, of The Joint Commission, writes in a commentary. "However, it does suggest that although disparities are usually due to a combination of who you are (individual characteristics) and where you go for care (structural factors), for outcomes after COVID-19 hospitalization, the latter plays the larger role and must be addressed if we are to eliminate disparities."

He adds, "Many hospitals in predominantly Black communities continue to face financial challenges and limited resources, and structural racism contributes to this."
Jun 17 JAMA Netw Open study and commentary

COVID immune responses diverse; stronger, earlier one may predict protection

A study that followed antibody, B cell, and T cell response in British doctors 6 months after COVID-19 infection found that participants' immune responses were diverse but followed some patterns that might predict protection against later infection, including against variants. A team from Oxford University published their findings on the Research Square preprint server.

Researchers analyzed monthly blood samples from 78 doctors who had either asymptomatic or symptomatic COVID-19 infections between April and June 2020. Using a machine-learning system, they looked for an indicator that might predict longer-term immunity, and they found that it didn't last long for those who had asymptomatic infections or a weak initial immune response.

Their findings also revealed that those who had a weak response didn't mount neutralizing antibodies against the Alpha (B117) or Beta (B1351) variants. Of doctors who had symptomatic infections, about three quarters had an immune response 6 months later.

"Overall memory responses to SARS-CoV-2 show distinct trajectories following early priming, that may define subsequent protection against infection and severe disease from novel variants," the group wrote.
Jun 15 Research Square preprint

Seropositive tests show low risk for COVID-19 reinfection in Italy

In 6,074 Italians, COVID-19 infection risk was less than 6% in those who were previously infected, according to a study yesterday in Clinical Infectious Diseases. The researchers note this was before the recent variants of concern were identified.

The cohort consisted of about 77% of the residents in the Trento province. The median age was 50, and those under 10 years old or those in nursing homes were excluded. In May 2020, the researchers found that 23.1% had immunoglobulin G (IgG) antibodies, indicating previous COVID-19 infection.

In a follow-up period from June 2020 to January 2021, 221 COVID-19 cases were identified, 4 among the seropositive group. Of those, two were symptomatic, with the worst affliction in an 88-year-old male who was admitted to the hospital but did not require mechanical ventilation or intensive care. Overall, the seronegative group saw a 2.60% cumulative incidence compared with the seropositive group's 0.14% cumulative incidence. The adjusted relative risk rate for reinfection was 0.06 (95% CI, 0.01 to 0.22).

"In line with what was observed elsewhere, our findings suggest that the relative risk of symptomatic infection for individuals who previously tested positive to IgG antibodies compared to seronegative subjects is less than 6%," the researchers write.
Jun 16 Clin Infect Dis study

Routine pediatric vaccines drop during COVID-19

Routine pediatric vaccine administration declined in all children during stay-at-home orders in southern California, but children older than 2 saw less coverage recovery, according to a Pediatrics study today.

The researchers compared the 2019 and 2020 pediatric populations in the Kaiser Permanente Southern California healthcare system, which had 987,554 and 992,971 patients, respectively. The researchers considered January through March pre-pandemic months, April through May pandemic months (as this was during California's stay-at-home order), and June to August as the reopening months in 2020.

Compared with the corresponding months in 2019, total and measles-containing vaccine administration declined during the pandemic months (-25.2% for those under age 2, -83.0% for those 2 to 6, and -87.6% for those 13 to 18). During the reopening period, vaccine administration largely recovered for those under 2 years old (-5.2%) but not for older children (-26.4% for those 2 to 6 years old and -49.3% for those 13 to 18).

Measles-containing vaccine administrations not only decreased less in those younger than 2 (-41.4% vs -83.4%) but also recovered more (-14.4% vs -26.6%). Because 16-month-olds saw a decline in coverage that worsened over time, the researchers say there could still be an increased risk of measles outbreaks, particularly in day-care settings.

During the stay-at-home order, complete vaccination coverage did not significantly change for those ages 7 to 17, but it did decrease in those below 2 years of age. Reopening led to the partial recovery of vaccination coverage in those under 2 but less so in those older. The researchers note, however, that complete vaccination coverage during June through August was lower in 2020 than in 2019 in all age cohorts, particularly those 7 months old (-12.3%) and those 17 years old (-11.9%).

"In addition, whereas administrations in all racial and ethnic groups plummeted during the stay-at-home period in 2020 compared with 2019, recovery was lower in non-Hispanic Black individuals than in other racial and ethnic groups during the reopening period, despite similar age distribution," the researchers write.
Jun 17 Pediatr study