Results of an ongoing phase 2 clinical trial show that an experimental vaccine given to pregnant women substantially reduced the risk of group B streptococcus infection in their infants.

A team led by the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit evaluated the safety and antibody levels in infants after their mothers received one dose of different formulations of Pfizer's hexavalent (six-strain) GBS6 vaccine or a placebo in the second or third trimester of pregnancy. A total of 17,752 women were included.

Over the same period (March 2019 to June 2020), the team also assessed which antibody concentrations were tied to a lower risk of invasive strep infection in infants up to 89 days old. Twenty-eight infants developed streptococcal disease and were studied in combination with a group of 90 infants with invasive disease retrospectively enrolled.

The research was published today in the New England Journal of Medicine. Group B strep transferred from mothers to newborns before or during delivery can cause sepsis, pneumonia, meningitis, and long-term neurologic impairment in infants.

75% to 95% risk reduction

Concentrations of immunoglobulin G (IgG) of 0.184 to 0.827 micrograms per milliliter in infants were linked to reductions in disease risk of 75% to 95%. Mother-to-infant antibody ratios were roughly 0.4 to 1.3, depending on the dose.

Overall, 57% to 97% of infants had detectable antibodies to the vaccine formulation that provoked the strongest immune response.

No vaccine-associated safety signals were detected in mothers or infants, but there were more local adverse reactions in mothers and infants who received GBS6 containing aluminum phosphate.

In a commentary in the same journal, Carol Baker, MD, of the University of Texas, said that GBS6 licensure could occur via an accelerated pathway based on the established serologic correlate of protection and confirmation of effectiveness.

"The authors take a novel and valuable step toward the goal of victory over the global public health challenge of group B streptococcal perinatal disease," she wrote.

University of Pittsburgh scientists report in Vaccine that, in adults, both recombinant influenza vaccine (RIV4) and standard-dose influenza vaccine (SD-IIV4) have low to modest effectiveness against influenza hospitalization, but RIV4 provides better protection compared with SD-IIV4 overall, with notable added protection in women, working-age adults, and those with no high-risk conditions.

The retrospective test-negative case-control study was based on hospitalizations and electronic medical records from a large US health system in the 2018-19 and 2019-20 flu seasons. The main outcome was the relative vaccine effectiveness (rVE) of RIV4 compared with SD-IIV4 among adults ages 18 and older. RIV-4 is Flublok Quadrivalent, made by Protein Sciences Corporation without using eggs. The authors compared it to five SD-IIV4 vaccines.

A total of 14,590 case-patients hospitalized for acute respiratory infections were included in the study, of which 3,338 were vaccinated with RIV4 and 976 were vaccinated with SD-IIV4. The other case-patients were unvaccinated against flu. Test results showed 12% were positive for influenza (1,803).

Influenza patients were mostly white (80%), had a high-risk condition (70%), and 65 years or older (53%). The patients who had been vaccinated with RIV4 were more often non-white, aged 65 years or older, and had more high-risk conditions than those who received SD-IIV4.

31% greater protection for recombinant vaccine

Overall, the vaccine effectiveness of RIV4 was 36% against influenza hospitalization (95% confidence interval [CI], 27% to 45%) and for population subgroups based on sex, age and risk conditions. The VE of SD-IIV4 was significant overall (24%; 95% CI, 6% to 38%) and for males and younger adults, but not for other subgroups. Overall rVE was 31% (95% CI, 11% to 46%).

Subgroup analyses by age and risk group showed significant rVE for RIV-4 among women (rVE of 37%; 95% CI, 13% to 54%), adults 18 to 64 years old (rVE of 28%; 95% CI, 3% to 46%) and for those without high-risk conditions (rVE of 60%; 95% CI, 29% to 78%).

"Relative vaccine effectiveness of RIV4 compared with SD-IIV4 was significant for all adults and for younger and healthier recipients," the authors concluded.

Two UK virologists yesterday called on governments to eliminate fur farming, especially mink, as a pandemic preparedness step. Thomas Peacock, PhD, and Wendy Barclay, PhD, both with Imperial College London, detailed their concerns in the Proceedings of the National Academy of Sciences.

They said mink farming is more widely practiced across the world than other type of fur farming, and that some countries and regions have phased it out, mainly due to ethical concerns. However, recent SARS-CoV-2 spillover events in minks and recent H5N1 avian flu detections in foxes and minks are a reminder that fur farming can lead to the rapid spread of viruses with pandemic potential and serve as a mixing vessel for virus adaptations to humans.

At the very least, biosecurity practices and active surveillance at fur farms must be reviewed, greatly enhanced, and closely enforced.

SARS-CoV-2 continues to circulating in mink, including strains that no longer circulate in humans, posing a risk of reintroduction, they wrote. Mink, like ferrets, have cell receptors for flu viruses that are similar to humans, and they note that a 2022 H5N1 avian flu outbreak at a Spanish mink farm yielded a virus that had at least one mammalian adaptation in the polymerase gene. "In all likelihood, we narrowly escaped a larger disaster, as the incident appears to have been contained," Peacock and Barclay wrote.

Mink could provide an ample opportunity for reassortment between H5 avian flu subtypes and human-adapted flu strains, they warned. Fur farming should be in the same high-risk category as bush meat trade and live-animal markets, they concluded. "At the very least, biosecurity practices and active surveillance at fur farms must be reviewed, greatly enhanced, and closely enforced."

A policy paper from the American Society for Microbiology (ASM) calls on policymakers to prioritize science and the role of microbiologists in the fight against antimicrobial resistance (AMR).

The paper, published yesterday, identifies areas where policies should be strengthened and presents recommendations for science-based solutions to address AMR through a One Health framework. In doing so, ASM emphasizes the role of microbiologists in conducting research, developing new drugs and diagnostics, and promoting responsible antibiotic use.

"ASM has made addressing the AMR crisis a top priority," the group writes. "Our members around the world are at the forefront of efforts to combat antimicrobial resistance, investigating how microbes interact and persist in living organisms and the environment, how they develop resistance, and how we can prevent, detect and treat antimicrobial resistant infections."

Arguing that current policies at the domestic and international level are falling short, the group recommends that policymakers support and strengthen the microbiology workforce in public health, laboratory, veterinary, and research settings; support innovative research into AMR to better understand the science of microbes and how resistance emerges and spreads; modernize data collection to ensure that testing and tracking in humans and animals keeps pace with evolving microorganisms; and champion solutions that address the challenging antibiotic marketplace and incentivize development of new antibiotics, antifungals, and alternative therapies.

Our members around the world are at the forefront of efforts to combat antimicrobial resistance, investigating how microbes interact and persist in living organisms and the environment, how they develop resistance, and how we can prevent, detect and treat antimicrobial resistant infections.

Other recommendations include improving detection models for resistant pathogens and outbreaks in hospitals and on farms; fostering antimicrobial stewardship in humans, animals, and crops; increasing lab capacity in low- and middle-income countries; and promoting efforts to develop a global assessment of AMR.

"As AMR increases in the U.S. and around the world, ASM and its members stand ready to work with Congress, federal agencies and global governing bodies to develop a One Health approach to advance science and practice to protect human and animal health, the economy and society at large," the paper concludes.

• A tornado that struck Rocky Mount, North Carolina, yesterday damaged a Pfizer facility that produces anesthesia and other drugs, along with 25% of the sterile injectables used at US hospitals, which could lead to shortages, according to NBC News. On Twitter, Pfizer confirmed that the facility was damaged and all employees were safe. It added that it was assessing the situation to determine the impact on production.
• Seven pharmaceutical companies today announced the launch of the INTREPID (International Readiness for Preventing Infectious Viral Disease) Alliance to speed the discovery and development of new antiviral treatments for use in future pandemics. In a press release, the group said the effort supports the "100 Days Mission" established by G7 countries, which has a goal of having 25 antivirals for viral diseases with pandemic potential ready for phase 2 and phase 3 trials by 2026. As a first step, the INTREPID Alliance plans to publish an initial list later this year. The companies are AbbVie, Amgen, Gilead, Johnson & Johnson, Novartis, Roche, and Takeda.
• Vir Biotechnology today announced that its candidate intramuscular monoclonal antibody for preventing influenza A (VIR-2482) did not meet the primary and secondary end points in a phase 2 trial. The company noted, however, that the drug, given as a single dose, was well tolerated, with no safety signals. Company officials said though the findings were disappointing, they plan on further analysis to understand the outcomes. Vir also said it is working on a neuraminidase-targeting monoclonal antibody (VIR-2981) that targets influenza A and B.