Following an advisory group discussion last week on COVID-19 vaccine updates for the fall, the Food and Drug Administration (FDA) on Jun 16 asked manufacturers to develop monovalent (single-strain) vaccines that target the Omicron XBB.1.5 subvariant.

The announcement followed a unanimous vote from the FDA Vaccines and Related Biological Products Advisory Committee (VRBPAC) to switch to a monovalent vaccine for the fall. After hearing data from federal experts and the vaccine companies, VRBPAC members expressed a preference for the XBB.1.5 subvariant.

Novavax last week said its XBB.1.5 candidate prompts a functional immune response against XBB.1.5, XBB.1.16, and XBB.2.3 subvariants, suggesting that its adjuvanted protein-based vaccine may be useful against drifted subvariants. In the United States, XBB.1.5 is most common, but the proportion is declining as newer XBB subvariant levels rise.

The FDA said in an addendum to its strain selection announcement that although the XBB sublineages continue to evolve, the spike protein sequences of XBB.1.5, XBB.1.16, and XBB.2.3 are similar, with few amino acid differences.

In its presentation to VRBPAC last week, a representative from Pfizer said the company could begin distributing doses of an XBB.1.5 monovalent vaccine by the end of July, but it would take a month longer to start distributing an XBB.1.16 vaccine. Any other formulation would have an October distribution schedule.

Interviews with clinicians who provided direct patient care at US healthcare facilities in the second year of the COVID-19 pandemic describe a disconnect between official messaging about crisis conditions and their own experience, waning morale, and having to allocate scarce resources in the absence of system-level support

The interview results were published by a University of Washington–led research team late last week in JAMA Network Open.

Twenty-three clinicians, including 21 doctors and 2 nurses, practicing in California, Idaho, Minnesota, or Texas completed interviews from December 28, 2020, to December 9, 2021. The average age was 49 years, 85.7% were White, and 57.1% were men.

Hospital plans may be 'unworkable'

Three themes emerged from the interviews: isolation, in-the-moment decision-making, and eroding motivation. Clinicians said they had a limited view of events outside of their immediate practice area and observed a disconnect between official messaging about conditions and their own experience.

"In the absence of overarching system-level support, responsibility for making challenging decisions about how to adapt practices and allocate resources often fell to frontline clinicians," the study authors wrote.

Interviewees said that formal crisis declarations didn't help guide allocation of resources in clinical practice, leaving them to rely on their clinical judgment and manage situations that were operationally and ethically complex.

Institutional plans to protect frontline clinicians from the responsibility for allocating scarce resources may be unworkable.

While a strong sense of mission, duty, and purpose had pushed clinicians to put forth extraordinary efforts early in the pandemic, interviewees said their motivation lessened over time due to unsatisfying clinical roles, a lack of alignment between their own values and those of their institutions, more distant relationships with patients, and moral injury.

"The findings of this qualitative study suggest that institutional plans to protect frontline clinicians from the responsibility for allocating scarce resources may be unworkable, especially in a state of chronic crisis," the researchers wrote. "Efforts are needed to directly integrate frontline clinicians into institutional emergency responses and support them in ways that reflect the complex and dynamic realities of health care resource limitation."

Brazilian health officials have reported a fatal swine-origin variant H1N1 (H1N1v) case to the World Health Organization (WHO), which the group says is part of a sporadic pattern with the virus in the country, with no evidence of human-to-human spread.

The patient is a 42-year-old woman from Parana state who had underlying health conditions. Her symptoms began on May 1, and she was hospitalized 2 days later. She died from her infection on May 5.

Testing at the state lab revealed that the virus was an H1 virus and of swine origin. Follow-up tests at the Oswaldo Cruz Institute revealed H1N1v, and sequencing showed that the sample was similar to other recent H1N1v samples from Parana state and was 96% similar to the hemagglutinin from swine viruses collected from Brazilian pigs in 2015.

Close contacts worked at pig farm

Investigators found that the woman lived near a swine farm, though she had no direct contact with the animals. Two of her close contacts, however, worked at the swine farm. Neither had symptoms or tested positive for flu, and the WHO said no human-to-human transmission has been identified.

The WHO said the H1N1v case is Brazil's first of 2023. Officials reported two earlier cases, one in 2021 and one in 2022. All were in Parana state. The WHO said the country continues to report sporadic H1N1v and H1N2v cases. Human infections with variant flu viruses are often mild, but some severe, even fatal, cases have been reported.

• Bavarian Nordic today reported promising phase 3 clinical trials findings for its chikungunya vaccine in people age 65 and older. In a statement, it said the immunogenicity exceeded the threshold established for by regulatory authorities and that neutralizing antibodies were observed in most participants 15 days after a single dose. The adjuvanted virus-like particle vaccine was well tolerated, with adverse event rates similar to placebo. The company is awaiting results for a larger phase 3 trial that enrolled adolescents and adults.
• The Coalition for Epidemic Preparedness Innovations (CEPI) yesterday announced a $2.1 million in research support for partners in Bangladesh and Malaysia to further epidemiologic knowledge about Nipah virus strain diversity in endemic countries, which is currently limited. Research projects will involve sequencing samples from people previously infected with Nipah and posting them to genomic databases. Also, researchers will examine data and publish their analyses in peer-reviewed publications and will sequence samples from new clinical Nipah virus cases. All earlier work was done on just two virus strains. Earlier this year, Bangladesh experienced an outbreak linked to raw palm date juice, which sickened 14 people, 10 of them fatally.
• The Centers for Disease Control and Prevention (CDC) Advisory Committee for Immunization Practices (ACIP) will meet tomorrow through Jun 23 to discuss several vaccine topics. Tomorrow the group will vote on a recommendation for use of Pfizer and GSK respiratory syncytial virus (RSV) vaccines in seniors. Members will also vote on issues related to polio and flu vaccines. On Jun 22 ACIP will vote on a pneumococcal vaccine topic, and on Jun 23 the experts will discuss mpox, meningococcal, and COVID-19 vaccines, though there are no votes scheduled.