Ahead of the Martin Luther King Jr holiday weekend, federal health officials announced that they were looking into a potential stroke risk in seniors who received the Pfizer-BioNTech bivalent (two-strain) COVID-19 booster. However, follow-up investigations in the United States and other countries and by the company have not found the same signal.

In a Jan 13 statement, the Food and Drug Administration (FDA) said it and the Centers for Disease Control and Prevention (CDC) said the CDC's Vaccine Safety Datalink (VSD) system, which tracks vaccine safety in nearly real-time, met the statistical level to prompt an investigation into whether there is a safety concern about whether people ages 65 and older who received the new Pfizer booster were more likely to have an ischemic stroke in the 3 weeks following vaccination compared to 22 to 44 days after vaccination.

It's unlikely that the signal in the VSD represents a true clinical risk.

The FDA said the preliminary signal hasn't been seen with the Moderna bivalent booster and that there may be other confounding factors in the VSD that require further investigation. It added that no signs of an increased stroke risk have been found in three other federal vaccine safety tracking databases. Also, the signal hasn't turned up in Pfizer's global safety database or in monitoring systems in other countries.

Considering all the data, it's unlikely that the signal in the VSD represents a true clinical risk, the FDA said, adding that it's important to share information about any potential safety signal with the public. The FDA's vaccine advisory committee will discuss the issue at its Jan 26 meeting.

In light of the new development, federal officials said there are no changes in COVID-19 vaccination recommendations, which is for everyone ages 6 months and older to stay current with their COVID-19 vaccinations, including those who are eligible to receive the bivalent boosters, which target the original virus plus Omicron variants.

The cost of COVID-19–related hospitalization in Spain was €1.23 billion ($1.33 billion US) in 2020, Spanish researchers reported late last week in JAMA Network Open.

The nationwide, population-based, retrospective economic evaluation of COVID-19 hospitalizations in Spanish hospitals found that 217,106 patients with a COVID-19 diagnosis (56.5% male, mean age 67.1 years) were admitted in 2020, with a mean cost per patient of €5,684.79 ($6,480.66). The cost per wave was €623 million ($710 million) in the first wave and €611 million ($696 million) in the second wave.

Intensive care unit admissions accounted for 9.5% of all admissions, with a much higher mean cost per patient (€21,199.20/$24,156.83) than general-admission patients (€4,122.96/$4,700.17). Higher mean costs per patient were also found in those who died (€8,774.72/$10,003.18) versus those who survived (€5,069.89/$5,779.67) and in men (€6,521.21/$7,126.38) compared with women (€4,950.49/$5,643.56).

Expenditures for COVID-19 patients represented 6.7% of total hospitals costs in 2020. The mean cost per COVID-19 patient was lower than reported costs in Canada, Greece, and the United States, but higher than reported in Turkey and Colombia.

"Results of this economic evaluation may be useful to health authorities for developing an economic strategy in preparation for future pandemics," the study authors wrote.

International efforts to address antimicrobial resistance (AMR) vary considerably between countries, with notable weakness in monitoring and evaluation, according to an analysis of AMR National Action Plans (NAPs) published yesterday in The Lancet Infectious Diseases.

For the analysis, a team of researchers from Scotland and Germany used a governance framework to assess all publicly available NAPs developed and implemented since 2017, when 194 World Health Organization (WHO) member states made a commitment to develop multisectoral NAPs using a One Health approach.

The framework consisted of 54 indicators pertaining to 18 domains that focus on three main areas relevant to global health governance: policy design, implementation tools, and monitoring and evaluation. The researchers used national data from five sources to generate composite scores for each country, then ranked the countries by their mean score on a scale of 0 to 100.

Of the 306 NAPs identified through a literature search, 114 were eligible for content analysis. Country governance scores ranged from 85 in Norway to 28 in Micronesia, with a mean overall score of 51. When ranked by WHO region, the European Region had the highest governance score (57) and the Eastern Mediterranean Region had the lowest score (46). Of the 20 countries with the highest scores, 17 were high-income countries; of the 20 lowest-scoring countries, 8 were upper-middle-income countries, and 7 were lower-middle-income countries.

The international response ... might not be commensurate with the scale and severity of antimicrobial resistance.

The highest-scoring domain across all countries was participation (83), followed by infection prevention and control (73) and coordination (63). The lowest-scoring domains were accountability (30) and feedback mechanism (30). Domains relating to policy design (55) and implementation tools (54) scored similarly, whereas monitoring and evaluation efforts (38) were lower.

"Our results show substantial variability in the strategic responses to antimicrobial resistance of 114 countries and highlight the need to improve relevant governance and policy responses in all locations," they wrote. "These data suggest that the international response, including efforts to monitor and evaluate interventions, might not be commensurate with the scale and severity of antimicrobial resistance." 

Researchers with the Centers for Disease Control and Prevention and the Minnesota Department of Health late last week reported an increase in infections caused by a multidrug-resistant (MDR) strain of Salmonella linked to pigs.

In a study published in Emerging Infectious Diseases, the researchers looked at data from five national surveillance systems to describe the epidemiology, antimicrobial resistance, and molecular genetics of infections caused by Salmonella enterica I serotype 4, [5], 12:i:-, which is the fifth most commonly reported illness-causing Salmonella serotype in the country. Infections caused by this strain have been rising since the 1990s, and recent years have seen the emergence of isolates in this strain with resistance to ampicillin, streptomycin, sulphamethoxazole, and tetracycline (ASSuT).

Among Salmonella isolates reported to the Laboratory-based Enteric Disease Surveillance System from 2009 to 2018, 19,212 (4.3%) from 37 states were 4, [5], 12:i:-. Forty-nine percent of the 4, [5], 12:i:- isolates included in National Antimicrobial Resistance Monitoring Systems surveillance had a resistance pattern that included ASSuT, and 35% had only ASSuT resistance. From 2009-2013 to 2014-2018, the frequency of 4, [5], 12:i:- infections rose from 3.7% to 4.9% of reported Salmonella infections, and the percentage of 4, [5], 12:i:- with ASSuT resistance rose from 1.1% to 2.6%.

Among isolates sequenced by PulseNet from 2015 to 2018, 69% were in the same MDR phylogenetic clade, and 77% of the isolates within that clade had genetic determinants of ASSuT resistance, while 16% had genetic determinants of decreased susceptibility to ciprofloxacin, ceftriaxone, or azithromycin.

Among MDR 4, [5], 12:i:- outbreaks reported from 2009 to 2018, 63% were associated with pork consumption or contact with swine.

"Our findings indicate that 4,[5],12:i:- infections have increased in the United States because of an MDR clade that has expanded since 2010," the study authors wrote. "Illness is likely to have resulted from transmission from swine that carry it. Further selection for this strain in swine might be prevented by limiting unnecessary agricultural use of classes of antibiotics to which the strain has resistance and by limiting unnecessary use of heavy metals in feed."

Illness is likely to have resulted from transmission from swine that carry it.