Omicron subvariants gain more ground, including BA.4.6 in the Midwest

Though the 7-day average for new daily COVID-19 cases is slowly declining, the more transmissible and immune-evasive Omicron subvariants became even more dominant last week, with an offshoot called BA.4.6 gaining traction in some Midwestern states.

As health officials brace for a possible spike in activity after school starts and people begin gathering more indoors in the fall, new surveys shed light on vaccination uptake prospects, both in kids and in adults ages 50 and older.

Highest BA.4.6 proportions in Iowa, Kansas, Missouri, Nebraska

In its weekly variant proportion updates today, the Centers for Disease Control and Prevention (CDC) said the proportion of BA.5 viruses in sequenced samples last week rose from 84.5% to 87.1%, while BA.4 declined slightly, from 8.2% to 6.6%. However, the proportion of BA.4.6 viruses rose from 4.2% last week to 4.8% this week.

Midwestern states—Iowa, Kansas, Missouri, and Nebraska—are seeing the highest BA.4.6 proportions, where it makes up 13.2% of sequenced specimens. The subvariant has also been reported in other US regions, especially in the east.

Meanwhile, the number of COVID-19 cases in children last week grew for the fourth consecutive week, the American Academy of Pediatrics said in its latest weekly update. Nearly 97,000 cases were reported for the week ending Aug 4, and kids' illnesses are trending upward just ahead of the start of the new school year.

Polls shed light on vaccine uptake ahead

A recent poll from the Kaiser Family Foundation that assessed parents' views on vaccinating their children against COVID-19 found that many were reluctant owing to worries about safety and not enough testing. Others expressed concerns about access barriers. Nearly half of Black parents said they were concerned about taking time off work to get their young children vaccinated, and nearly half of Hispanic parents had concerns about getting their child vaccinated at locations they trust.

Also, a majority of parents of children under 5 said messaging about the vaccine from federal officials is confusing, especially where to get to the vaccine.

Meanwhile, a new poll from the University of Michigan revealed that 61% of people older than 50 who have already had at least one dose of COVID-19 vaccine are likely to get vaccinated this fall with updated boosters that will include an Omicron variant component. Levels were highest in seniors, Black adults over 50, and low-income groups.

Also, the poll suggested that intention to get the updated booster might increase if health providers specifically recommend them.

In other COVID developments:

  • An attorney general group of 23 states argued in a federal appeals court yesterday that the CDC lacks the authority to impose a national mask mandate on public transport to address COVID-19.
  • The European Medicines Agency (EMA) announced today that it has started a rolling review of an updated booster from Pfizer/BioNTech that includes the BA.4/5 Omicron subvariant strain, according to Reuters. In July, the EMA announced a similar review process for the different version of the booster that pairs the original virus with BA.2.

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