In 2022, the median global COVID-19 vaccination rate among people aged 60 and older—who make up over 80% of deaths from the virus—was 76%, substantially lower than the World Health Organization (WHO) goal of 100%, according to a study today in Morbidity and Mortality Weekly Report. Low- and middle-income countries (LMICs) had particularly low uptake.

Researchers from the US Centers for Disease Control and Prevention and the WHO parsed data on COVID-19 deaths in 2020 and 2021 and recent vaccine coverage data to estimate death rates and vaccine uptake among people 60 and older by country and World Bank income status.

In fall 2020, the WHO published a plan for prioritizing COVID-19 vaccination, followed by a strategy brief in October 2021 and a July 2022 update prioritizing at-risk people, including older adults. The goal was 100% coverage with a complete COVID-19 vaccine series for this group by mid-2022. 

10 times more excess deaths in LMICs

Surveillance and weekly reports documented 5.4 million and 2.5 million COVID-19 deaths in 2020 and 2021, respectively. The WHO model showed an estimated 14.9 million excess deaths. People 60 and older made up 80% of COVID-19 deaths reported through surveillance and 82% of deaths from the WHO's model.

In 73% of low-income countries and 31% of lower–middle-income countries (mostly in the WHO's African, Eastern Mediterranean, and European regions), estimated excess mortality was more than 10 times higher than the total deaths reported through surveillance, while most high-income countries saw a doubling of excess deaths. 

Upper- and lower–middle–income countries accounted for 81% of excess deaths among people 60 and older, and lower–middle–income countries made up 52% of excess deaths in this age-group (annual excess death rate, 1,039 per 100,000 people).

Despite the heavy burden, the median 2022 vaccination rate in the over-60 group was 76% (range, 33% in low-income countries to 90% of those with higher incomes). "Increased efforts are needed to increase primary series and booster dose coverage among all older adults," the researchers wrote.

A secondary analysis of results from a phase 3 clinical trial found that an investigational microbiome therapeutic for treatment of recurrent Clostridioides difficile infection (rCDI) was associated with significant quality-of-life improvements compared with placebo, researchers reported this week in JAMA Network Open.

The analysis looked at data from the randomized, double-blind ECOSPOR III trial, which randomized adults with rCDI to receive four daily doses of SER-109—a therapeutic composed of Firmicutes bacterial spores—or a placebo for 3 days. Previously published results from the trial have shown that SER-109, which was developed by Seres Therapeutics, was superior to placebo for treatment of rCDI 8 weeks after dosing and well-tolerated.

For this study, researchers looked at scores on the Clostridioides difficile Quality of Life Survey (Cdiff32), a disease-specific, health-related quality-of-life (HRQOL) survey completed by 182 trial participants (89 in the SER-109 group and 93 in the placebo group) at baseline, week 1, and week 8.

Scores were similar between patients in the SER-109 and placebo groups at baseline (52.0 vs 52.8, respectively). But the proportion of patients with improved HRQOL outcomes from baseline in the total Cdiff32 score and physical domain and subdomain scores was significantly higher in the SER-109 group than the placebo group at week 1 (49.4% vs 26.9%) and week 8 (66.3% vs 48.4%).

Among patients in the placebo group, improvements in HRQOL were primarily observed in patients with nonrecurrent CDI, while patients in the SER-109 group reported improvements in HRQOL regardless of clinical outcome.

The study authors also note that patients in the SER-109 group showed greater improvement in the mental domain and subdomain scores, which may suggest the potential role of the microbiome in mood-related disorders related to the gut-brain axis.

"These data suggest that an investigational microbiome therapeutic not only offers the clinical benefits of reduced CDI recurrence, but may also improve HRQOL, an important patient-reported outcome of great interest to patients, clinicians, payers, and regulators," they wrote.

Tests on mammal species in the United Kingdom have found H5N1 avian influenza in red foxes and otters, according to notifications from UK animal health officials, part of a growing number of detections in mammals in Europe and the Americas.

The UK detections range from animals collected in 2021 through the early weeks of 2023. The animals that tested positive—five foxes and four otters—were from England, Scotland, and Wales.

Spanish officials recently reported H5N1 in farmed minks, and veterinary authorities in Canada and the United States have reported several H5N1 detections in wild mammals, including seals, raccoon, skunks, and bears.

The H5N1 clade circulating on multiple continents has a mutation that makes it more recognizable by human airway cells. So far only seven human infections have been reported, all in people who had close contact with sick poultry. Some were asymptomatic, but some were severe or fatal.

More detections in US poultry, wild birds

The US Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS) recently reported more highly pathogenic avian flu outbreaks in poultry, according to notifications over the past few days.

In Maine, the virus struck backyard birds in Hancock County. Also, Pennsylvania reported two outbreaks, one at a commercial duck farm in Lancaster County that houses nearly 38,000 birds. The other apparently occurred at a commercial farm housing 3,200 birds, though the location wasn't specified. So far, US outbreaks have led to the loss of a record 58.2 million poultry across 47 states.

Also this week, APHIS reported 155 more H5N1 detections in wild birds, raising the total since January 2022 to 6,111. The birds that tested positive were from a broad section of the United States, but most were from the West and South, including several positive test results in geese and black vultures found dead.