News Scan for Apr 25, 2022

News brief

COVID vaccines may have saved 19,000 lives in under a year in California

A modeling study estimates that COVID-19 vaccination prevented more than 1.5 million infections, 72,000 hospitalizations, and 19,000 deaths in the first 10 months of vaccination in California, according to a study published late last week in JAMA Network Open.

University of California researchers created a statistical model using person-level data from the California Department of Public Health to estimate COVID-19 cases that would have occurred if vaccination hadn't been widely available from Nov 29, 2020, to Oct 16, 2021. The study period included the Delta, but not the Omicron, variant surge.

During the study period, 3,276,260 COVID-19 cases, 240,718 hospitalizations, and 70,406 deaths occurred, and 164,680 eligible residents (aged 12 and older) received at least one dose of COVID-19 vaccine, for a vaccination rate of 79.5%. Roughly 57% of vaccinees received the Pfizer/BioNTech vaccine, while 36% received Moderna, and 7% received Johnson & Johnson.

"Both risk of hospitalization and risk of death varied over time and across age groups and was highest in the population aged 65 years or older (21.6% of reported cases resulted in hospitalization and 10.8% of reported cases resulted in death)," the study authors wrote.

According to the model, COVID-19 vaccination prevented 1,523,500 infections (95% prediction interval [PI], 976,800 to 2,230,800), corresponding to a 72% (95% PI, 53% to 91%) relative reduction. Vaccination also averted an estimated 72,930 hospitalizations (95% PI, 53,250 to 99,160) and 19,430 deaths (95% PI, 14,840 to 26,230).

The authors said that the estimates are likely a lower bound and that the results may be generalizable to the rest of the United States.

"The primary model and alternative model estimated that more than 65% to 90% of averted COVID-19 cases occurred after the Delta variant became the prominent variant of SARS-CoV-2 circulating in California, with similar estimates of averted hospitalizations and deaths," they wrote. "The value of vaccination is likely to be larger with the emergence of more transmissible variants, such as the Omicron variant."
Apr 22 JAMA Netw Open study

More evidence COVID-19 in pregnancy can lead to severe outcomes

More evidence that pregnant women with COVID-19 have more severe outcomes than non-pregnant peers was presented at this year's European Congress of Clinical Microbiology & Infectious Diseases (ECCMID). The research also showed even one dose of vaccine was protective against hospitalization for COVID-19.

The study, conducted by researchers at the University of Toronto, included data from 13,600 women from Ontario's Case and Contact Management database, and matched every pregnant woman with 5 non-pregnant women as time-matched controls to account for different circulating strains and vaccine availability. Case-patients were included from Mar 6, 2020 through Jan 4, 2022.

The researchers adjusted outcomes for age, other illnesses, healthcare worker status, vaccination, and infecting variant. Though pregnant women were half as likely as non-pregnant peers to contract COVID-19, they were five times as likely to be admitted to hospital with COVID-19 compared to their non-pregnant peers, and were more than six times as likely to require treatment in intensive care.

Of note, the findings also indicate that all women were half as likely to be hospitalized after just one dose of the COVID-19 vaccine, and even less likely with two or more doses, the authors said.

"These findings suggest that in otherwise healthy women, pregnancy itself seems to be a factor that increases illness severity, while among women with comorbidities it becomes one of several factors that augment risk," said Kiera Murison, PhD, a lead researcher on the study, in an ECCMID press release. "Our findings underscore the need for clear accurate information to reassure pregnant women and tackle concerns about COVID-19 vaccine safety."
Apr 24 ECCMID abstract and press release

Avian flu strikes more poultry in 4 states

Four states reported more highly pathogenic avian flu outbreaks in poultry, including four more in Minnesota, where the virus has hit turkey producers especially hard.

Minnesota's latest outbreaks all involved turkey farms and lift the state's outbreak total to 54, with a loss of 2.46 million birds so far, according to an update from the Minnesota Board of Animal Health (MBAH).

Meanwhile, an update from the US Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS) notes outbreaks in three other states. North Dakota reported two more outbreaks, one at a turkey producer in Richland County housing 27,500 birds and the other at a backyard facility in Renville County. The state has now reported 13 outbreaks. Also, Wisconsin reported one more outbreak, its eighth, which struck a backyard flock of 40 birds in Polk County.

Elsewhere, the virus struck another commercial farm in Pennsylvania's Lancaster County, this time a broiler facility housing more than 50,000 birds. The state has now reported four outbreaks, all at commercial farms in Lancaster County.

The outbreaks are part of ongoing activity involving the Eurasian H5N1 strain, which has spread to poultry in 29 states and led to the loss of 31.36 million birds.
MBAH update
USDA APHIS poultry outbreak page

WHO says more pediatric hepatitis cases have been identified

The World Health Organization (WHO) over the weekend posted a new update on unexplained acute hepatitis in children. More countries have detected cases, and the WHO suggested that a possible link to adenovirus infections does not explain the severity of the illnesses.

So far at least 169 children in 11 countries have been diagnosed as having acute hepatitis of unknown etiology. Seventeen children have required liver transplants, and one child has died. Cases have been reported in countries across Europe, the United States, and Israel, with the United Kingdom reporting the most cases (114).

Most case-patients do not present with a fever, and instead report gastrointestinal symptoms including abdominal pain, diarrhea and vomiting, and increased levels of liver enzymes. Tests for hepatitis viruses A, B, C, D and E are negative.

"Adenovirus has been detected in at least 74 cases, and of the number of cases with information on molecular testing, 18 have been identified as F type 41. SARS-CoV-2 was identified in 20 cases of those that were tested. Furthermore, 19 were detected with a SARS-CoV-2 and adenovirus co-infection," the WHO said.

Though researchers around the world are exploring the link between the hepatitis cases and adenoviruses, the WHO said infection with adenovirus type 41, the implicated adenovirus type, has not previously been linked to such a clinical presentation. Adenovirus type 41 typically presents as diarrhea, vomiting, and fever, often accompanied by respiratory symptoms, the WHO said.

Adenovirus type 41 has not been known to cause hepatitis in previously healthy children.
Apr 23 WHO report

Stewardship / Resistance Scan for Apr 25, 2022

News brief

Antibiotic-resistant infections up in US hospitals during COVID, data show

Patients hospitalized during the COVID-19 pandemic and tested for SARS-CoV-2 had higher rates of antibiotic-resistant infections compared with those hospitalized before the pandemic, according to a study presented yesterday at the European Congress of Clinical Microbiology and Infectious Diseases (ECCMID 2022).

The multicenter retrospective cohort study by scientists with Merck and Becton, Dickinson and Company looked at data on adults admitted to 271 US hospitals before (July 2019 through February 2020) and during (March 2020 through October 2021) the COVID-19 pandemic. All admissions with an antimicrobial resistance (AMR) event, defined as a non-contaminated first positive culture for select gram-positive or gram-negative pathogens with non-susceptibility, were reported. AMR rates were further evaluated based on community-onset (CO) and hospital-onset (HO) infections.

Overall, there were 1,789,458 patients admitted in the pre-pandemic period and 3,729,208 admitted during the pandemic. The AMR rate was 3.54 per 1,000 admissions pre-pandemic and 3.47/1,000 admissions during the pandemic. But among patients who tested both positive and negative for SARS-CoV-2 during the pandemic, the AMR rate was 4.92/1,000 and 4.11/1,000, respectively. For HO infections, the AMR rate was 0.77/1,000 pre-pandemic and 0.86/1,000 during the pandemic—2.19/1,000 for those tested positive for SARS-CoV-2 and 1.00/1,000 for those who tested negative.

For CO infections, the AMR rate was 2.76/1,000 and 2.61/1,000 in the pre-pandemic and pandemic periods, respectively.

"These new data highlight the importance of closely monitoring the impact of COVID-19 on antimicrobial resistance rates," study co-author Karri Bauer, PharmD, said in an ECCMID press release. "It is particularly worrying that antibiotic resistance has been rising during the pandemic in both SARS-CoV-2 positive and negative patients. Hospital-acquired infections are a major concern, with antimicrobial resistance rates significantly higher during the pandemic than before."

Bauer and her colleagues say additional research on the pandemic's impact on AMR is needed.
Apr 24 ECCMID abstract
Apr 24 ECCMID press release

Danish study suggests potential C difficile spread between pigs, humans

A study conducted in Danish pigs found strains of Clostridioides difficile that were similar to those found in humans, with multiple resistance genes, researchers reported late last week at ECCMID.

In the study, researchers from the University of Copenhagen and Statens Serum Institut tested 514 samples collected in two batches from 14 Danish pig farms for the presence of C difficile. They also conducted whole-genome sequencing to determine the multilocus sequence type, toxins, and resistance genes, and to compare the pig isolates to isolates collected from human C difficile patients during the same period.

A total 54 pig samples from the two batches tested positive, with further analysis showing that C difficile was more common in piglets and sows than in slaughter pigs. All isolates were toxigenic, and 13 sequence types were found, all of which were also present in the human samples. The most prevalent sequence type in the pig and human isolates was ST11, and in 16 cases, the ST11 isolates in the pigs were nearly identical to the human isolates, a finding that suggests the potential for transfer between pigs and humans.

Thirty-eight isolates from pigs contained at least one resistance gene, and resistance was predicted for at least seven antibiotic classes, the most common being macrolides, beta-lactams, aminoglycosides, and vancomycin.

The study authors say deeper phylogenetic analysis would be needed to determine whether C difficile is spreading from pigs to humans or if transmission is bidirectional. But the identification of shared resistance genes is a concern, they say.

"Our finding of multiple and shared resistance genes indicate that C. difficile is a reservoir of antimicrobial resistance genes that can be exchanged between animals and humans," study co-author Semeh Bejaoui, PhD, said in an ECCMID press release. "This alarming discovery suggests that resistance to antibiotics can spread more widely than previously thought, and confirms links in the resistance chain leading from farm animals to humans."
Apr 23 ECCMID abstract
Apr 23 ECCMID poster
Apr 23 ECCMID press release

Johnson & Johnson launches drug-development center in South Africa

Pharmaceutical company Johnson & Johnson (J&J) today announced the launch of a new satellite center in South Africa that will focus on developing drugs to combat AMR.

According to a company press release, the J&J Satellite Center for Global Health Discovery at the Holistic Drug Discovery and Development (H3D) Centre at the University of Cape Town will bolster early-stage research and development with a focus on multidrug-resistant gram-negative bacteria, are is a threat in Africa and around the world. J&J officials say the center aims to boost Africa's scientific capacity as a global hub for discovery research, and will be part of a larger, global scientific network that will help stimulate local innovation.

"Investing to increase the capacity of the innovation ecosystem in Africa is critical to strengthening the R&D pipeline for entrenched and emerging global health challenges," said Ruxandra Draghia-Akli, MD, PhD, Global Head, Global Public Health R&D at Janssen Research & Development, LLC.

"By leveraging the unique strengths of H3D and the J&J Centers, we can cultivate the talent and capacity needed to drive innovation in the global fight against AMR."
Apr 25 J&J press release