COVID-19 Scan for Oct 28, 2021

News brief

New monoclonal antibody sharply reduces risk of severe COVID outcomes

The monoclonal antibody sotrovimab reduced the risk of hospitalization or death from COVID-19 by 85% compared with placebo, according to an interim analysis of a phase 3 clinical trial published yesterday in the New England Journal of Medicine.

In the double-blind, multicenter trial, non-hospitalized patients with symptomatic COVID-19 and at least one risk factor for disease progression were randomly assigned to receive either 500 milligrams of sotrovimab, a pan-sarbecovirus monoclonal antibody developed by GlaxoSmithKline and Vir Biotechnology, or placebo. Patients were recruited from Aug 27, 2020, and followed through Mar 4, 2021, and more than 60% were Hispanic or Latino—a population the investigators note has been underrepresented in COVID-19 clinical trials.

The primary outcome was the percentage of patients who were hospitalized for more than 24 hours or who died from any cause through 29 days after randomization.

Among the 583 patients included in the intention-to-treat population (291 in the sotrovimab group and 292 in the placebo group), 3 patients treated with sotrovimab (1%) had disease progression leading to hospitalization or death, compared with 21 patients (7%) in the placebo group (relative risk reduction, 85%; 97.24% confidence interval [CI], 44% to 96%). All 5 patients who were admitted to the intensive care unit were in the placebo group, as were 2 of the 5 received invasive mechanical ventilation.

Among the 868 patients in the safety population, adverse events were reported by 17% of patients in the sotrovimab group and 19% of the placebo group. Serious adverse events occurred in 2% of patients who received sotrovimab, compared with 6% of patients who received placebo.

The study authors note that sotrovimab was selected to have an intrinsically higher barrier to resistance as a result of targeting a pan-sarbecovirus epitope, which means it could remain effective against future coronavirus variants.

"Given its in vitro activity against variants of interest and concern, as well as its ability to neutralize other sarbecoviruses, we speculate that sotrovimab has the potential to remain therapeutically active even as SARS-CoV-2 continues to evolve," they wrote.
Oct 27 N Engl J Med study

Study highlights waning protection of Pfizer COVID vaccine against Delta

In another study published yesterday in the New England Journal of Medicine, Israeli researchers reported further evidence of waning effectiveness of the Pfizer/BioNTech COVID-19 vaccine against the more transmissible Delta (B1617.2) variant.

To estimate the role of waning immunity in breakthrough infections during Israel's summer wave of Delta variant infections, researchers collected data on confirmed SARS-CoV-2 infections and severe disease reported from Jul 11 to 31 among all Israeli residents who had been vaccinated with the Pfizer vaccine prior to June. They then compared rates of infection and severe COVID-19 among people vaccinated during different periods, with stratification according to age-group and adjustment for possible confounding factors.

Among more than 4.7 million fully vaccinated adults, 13,426 had confirmed SARS-CoV-2 and 403 had severe COVID-19. The rate of confirmed infection showed a clear increase as the time from vaccination increased for all age-groups. Among people age 60 and older, the rate of infection from Jul 11 to 31 was higher for those who were fully vaccinated in January 2021 than for those vaccinated in March 2021 (rate ratio, 1.6; 95% CI, 1.3 to 2.0). Among people ages 40 to 59, the rate of infection was 1.7 (95% CI, 1.4 to 2.1) times higher for those fully vaccinated in February compared with those fully vaccinated in April. For the age 16-to-39 group, the rate of infection was 1.6 (95% CI, 1.3 to 2.0) times higher for those fully vaccinated in March compared with those vaccinated in May.

The results were similar for severe COVID-19. Among fully vaccinated people ages 60 and older and 40 to 59, the rate ratios for severe disease were 1.8 (95% CI, 1.1 to 2.9) and 2.2 (95% CI, 0.6 to 7.7), respectively, for those fully vaccinated in January or February compared with those vaccinated in March. The rate ratio could not be calculated for those ages 16 to 39, given the small number of severe cases in this group.

The study authors say the findings provide an epidemiologic basis for the Israeli government's decision to approve booster shots in July for those who had been vaccinated at least 5 months previously. "The findings also suggest the need to follow the effects of waning immunity closely and to inform policymakers worldwide who are facing decisions regarding the administration of booster vaccinations," they wrote.
Oct 27 N Engl J Med study

Committee: Meatpackers' COVID-19 cases much higher than reported

A congressional committee's examination of documents from five of the nation's biggest meatpacking companies found that at least 59,000 meatpacking workers contracted COVID-19 and 269 died in the first year of the pandemic, almost triple the 22,700 cases previously estimated for the five firms by the Food and Environment Reporting Network.

The report is based on documents from JBS, Tyson Foods, Smithfield Foods, Cargill, and National Beef. Together the companies control over 80% of the beef market and over 60% of the pork market.

The 59,000 cases may even be an undercount. "Because data for Smithfield, Tyson, and National Beef may exclude positive coronavirus tests from community testing centers or other health providers, it is likely that the actual rate of coronavirus infections among these companies' workers was even higher than these companies' data reflects," the report says.

Several of the documents shared with the committee offered new information on dangerous working conditions, including sweat-saturated masks and flimsy plastic partitions between workers.

The committee's report included several examples of hot spot meatpacking plants, including a Tyson plant in Amarillo, Texas, where 49.8% of workers contracted the virus, and five people died. Other hot spots included a JBS plant in Hyrum, Utah, where 54% of the workforce contracted the virus, and National Beef’s plant in Tama, Iowa, where 44% of employees got the virus.
Oct 27 committee report

News Scan for Oct 28, 2021

News brief

Rapid test linked to improved antibiotic therapy for bloodstream infections

Use of a rapid diagnostic test in patients with bloodstream infections (BSIs) was associated with shorter times to optimal antibiotic therapy and antibiotic de-escalation, researchers reported yesterday in Clinical Infectious Diseases.

In the quasi-experimental, multicenter Improving Outcome and Antimicrobial Stewardship (IOAS) study, researchers compared clinical and antimicrobial stewardship metrics in BSI patients at 5 US hospitals before and after implementation of Accelerate PhenoTest BC Kit (AXDX) testing.

AXDX is a rapid diagnostic platform that provides pathogen identification and antibiotic susceptibility test (ID/AST) results from positive blood cultures up to 40 hours earlier than traditional methods. The primary outcomes were time to optimal therapy (TTOT) within 96 hours of blood culture positivity and 30-day mortality.

A total of 854 patients with BSI (435 pre-AXDX, 419 post-AXDX) were included in the study. Patient demographics, co-existing conditions, and baseline clinical characteristics were similar between the two groups.

Median TTOT was 17.2 hours shorter in the post-AXDX arm (23.7 hours) compared with the pre-AXDX arm (40.9 hours). Median time to first antimicrobial modification (24.2 vs 13.9 hours) and first antimicrobial de-escalation (36 vs 27.2 hours) were also shorter in the post-AXDX arm.

There was no statistical difference in 30-day mortality (8.7% pre-AXDX vs 6.0% post-AXDX) between in the two arms, or in the secondary clinical outcomes of length of stay and adverse events. Length of stay was shorter in the post-AXDX arm (5.4 vs 6.4 days) among patients with gram-negative bacteremia.

"This multicenter, real-world study suggests early ID/AST via AXDX has a significant impact on optimizing antimicrobial utilization and outcomes for patients with BSIs," the study authors wrote. "While challenging to demonstrate definitively, the value of early antimicrobial optimization is likely associated with widespread patient and societal benefits such as limiting the emergence of antimicrobial resistance and reduced harm from unnecessary antimicrobial exposures."
Oct 27 Clin Infect Dis abstract

CDC worried about low flu vax levels in kids, pregnant women

The US Centers for Disease Control and Prevention (CDC) said yesterday that it is worried about lagging flu vaccine uptake in children and pregnant women so far this season, based on its first coverage estimates for the groups.

For kids, flu vaccination is down 6% compared with the same time last year, which the CDC said is especially concerning, because coverage last season was already down because of COVID-19. And for pregnant women, the CDC is seeing a 15% drop from last year, spanning all racial and ethnic groups.

Younger children and kids with underlying health conditions face a higher risk of flu complications, as do pregnant women.

The CDC said with 137.7 million flu vaccine doses distributed so far, supply isn't likely the reason for immunization drops in the two groups. It added that other factors could include low flu activity last season, vaccine fatigue against the backdrop of COVID-19 vaccination, confusion about whether a flu vaccine is needed, and changes in healthcare-seeking behavior.

Officials also said a recent Harris poll suggested that one in four people believe the COVID-19 vaccine protects against flu and vice versa. It reiterated that the diseases are caused by different viruses and that one vaccine isn't a replacement for the other.
Oct 27 CDC statement

H5N1 avian flu strikes UK swan facility

Animal health officials in the United Kingdom reported a highly pathogenic H5N1 avian flu outbreak at a wild bird rescue facility in Worcestershire. Media reports said the facility houses swans.

In a statement, the UK's Department for Environment, Food, and Rural Affairs (DEFRA) said all birds at the site will be humanely culled, and protection zones have been established around the facility as part of measures to curb the spread of the virus. An investigation is under way to identify the source of the virus.

The new outbreak came on the heels of a DEFRA risk assessment this week that warned H5N1 could spread widely in wild birds and poultry in the cooler months ahead.
Oct 28 Irish Farmers Journal story
Oct 26 DEFRA statement
Oct 27 CIDRAP News scan