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Omicron’s split into fast-spreading lineages highlights coronavirus’s evolution

Scientists are tracking newer forms of the Omicron coronavirus variant, further evidence that even when a strain becomes globally dominant, it continues to evolve and can splinter into different lineages. Case in point: Updated data released yesterday showed that a burgeoning form of Omicron, called BA.2.12.1, now accounts for nearly one in five infections in the U.S. It’s eating into the prevalence of the ancestral BA.2, highlighting a transmission advantage over its parent. BA.2 now accounts for about 74% of cases, while 6% or so are from the BA.1 branch of Omicron, the first form of the variant that took over globally. Early signs suggest the different lineages don’t substantially differ in terms of how virulent they are or in their ability to evade the protection generated by immunizations. STAT’s Andrew Joseph has more.

Moderna data raise hopes for better Covid boosters — and questions

New data from Moderna offer hope that booster shots against Covid-19 could become at least somewhat more effective than they already are. But the data also point to how difficult it could be to determine which Covid shots to give as annual boosters. Moderna released data yesterday on testing a booster shot that is bivalent, containing equal mRNA amounts of ancestral SARS-CoV-2 and of spike proteins from the Beta variant of SARS-CoV-2. Although it does not contain vaccine targeted specifically against the Delta or Omicron variants, it generated antibodies that blocked Beta, Delta, and Omicron variants better than the existing Moderna Covid vaccine. A non-peer reviewed preprint published alongside the company’s news release noted it’s impossible to say whether the antibody boost provided by the bivalent vaccine prevents infections or severe disease better than the existing booster. STAT’s Matthew Herper explains.

Almost 9 in 10 kids hospitalized for Covid weren't vaccinated when eligible

Here’s the bottom line: Children continue to experience serious Covid-19 illness, yet most aren't vaccinated. A new CDC survey tracked kids hospitalized for Covid from late December through February — a period in which Omicron was the dominant coronavirus variant and after vaccines were authorized in November for 5- to 11-year-olds. Among 397 hospitalized children, 87% were unvaccinated, 30% had no underlying conditions, and 19% were admitted to ICUs. Non-Hispanic Black children made up the largest group of unvaccinated children, at 34%, and they accounted for about one-third of Covid hospitalizations. Children with diabetes and obesity were more likely to experience severe Covid. The researchers also note that as of March 5, only 32% of children in this age group had completed their primary vaccination series. “The potential for serious illness among children aged 5–11 years … highlights the importance of vaccination,” they write.

Closer look: What counts as a breakthrough?

(MOLLY FERGUSON FOR STAT)

On Monday, a STAT investigation revealed that five years after the FDA launched a program to speed the development and review of cutting-edge medical devices, its benefits to device makers have been big but its value to patients is still unclear. The breakthrough label has broad appeal to device makers: The FDA has granted the designation to a sprawling set of more than 650 products, from Elon Musk’s Neuralink brain-computer interface and Alzheimer’s disease tests to 3D-printed spinal implants and a bassinet that could help prevent sudden infant death syndrome. “When you look at these products, you have to sort of crane your neck a little bit,” said Ariel Stern of Harvard Business School. “What are the features, what are the aspects of this product that map back to the regulatory criteria?” STAT’s Katie Palmer and Mario Aguilar explore what “breakthrough” really means. Read more in STAT+.

Opinion: The 988 hotline has potential, but it will fail without investment

A new nationwide mental health and suicide prevention crisis hotline known as 988 — think of it as 911 for mental health crises — is scheduled to roll out in fewer than 100 days. Unfortunately, it’s far from ready, clinical psychologist Benjamin Miller writes in a STAT First Opinion. Implementing the program to replace the current National Suicide Prevention Lifeline number of 800-273-8255 has been hampered by a lack of sustainable federal funding. That’s consistent with how little the U.S. invests in mental health, Miller says: Too many people, especially children, are waiting too long for the care they need. “The 988 line has the potential to create new pathways for care,” he writes. “But without robust financing, clear communication, and strong leadership, the consequences of not getting 988 right are severe, and lives may be lost.”

Gender-minority students report more threats to their health

Most studies looking into health outcomes among people whose gender identity differs from their assignment at birth have focused on adults, researchers point out in a new JAMA research letter. To learn about the well-being of younger people, they perused state data from the 2017 and 2019 Youth Risk Behavior Surveys, for which 15 states asked high school students about gender identity (transgender, gender questioning, “I don’t know,” or no answer). Asked about bullying, sexual and dating violence, mental health and suicidality, sexual risk behaviors, and substance use, transgender and gender-questioning high school students — each group representing about 2% of students — were more than twice as likely as cisgender students to say they were bullied or considered suicide. Differences were even larger for physical dating violence, suicide attempts requiring medical treatment, and cocaine use.

On this week's episode of the "First Opinion Podcast," First Opinion editor Patrick Skerrett talks with Jasmine Travers and David Grabowski about the current state of affairs in nursing homes across the country, the important progress that needs to be made, and key steps for making improvements. Listen here.

What to read around the web today

‘It’s just scaring people, and it’s not saving lives.’ The Atlantic
Biden admin to rescind Trump ‘conscience’ rule for health workers. Politico
Adam's Take: What Regeneron’s purchase of Checkmate Pharma says about the state of biotech. STAT+
Better ventilation can prevent Covid spread. But are companies paying attention? Kaiser Health News
CDC launches new forecasting center for infectious diseases. Associated Press