US COVID markers continue slow rise as UK reports first BA.2.86 case

Sick guy blowing nose

Kateryna Onyshchuk / iStock

COVID hospitalizations and death rose last week, along with other indicators and the proportion of newer Omicron variants such as EG.5, the Centers for Disease Control and Prevention (CDC) said in its latest data updates.

Also, scientists in the United Kingdom have identified the country's first case involving BA.2.86, an Omicron variant under close watch due to its many mutations and the possibility that it may already be circulating in multiple world regions.

Activity intensifies amid rising EG.5, FL.1.5.1, XBB.1.16.6

The CDC's two main indicators, hospitalizations and deaths, both rose again from very low levels.

Hospitalizations for COVID-19 inched upward for the sixth straight week, increasing by 14.3% from the week before. More US counties are in the medium level for new admissions, especially in the South and Southeast. Only one county—Oregon's Grant County—is listed as high.

Deaths rose for the second week in a row, reflecting an increase of 8.3% from the week before. However, COVID-19 made up only 1.3% of deaths over the past week.

The CDC's early indicators also continue to rise. Emergency department (ED) visits were up 19% from the week before, with substantial increases reported across the South and Southeast. Elsewhere, ED visits showed a substantial increase in Oregon and moderate increases in California and Washington.

Test positivity rose 1.5% last week and is at 12.2% nationally. The region that includes Texas and surrounding states has the highest positivity level.

Biobot wastewater tracking shows a steady rise for most regions, except for the Midwest.

The CDC also updated its variant proportions today, which show another steady increase in the EG.5 viruses and further declines in XBB.1.5. The proportion of EG.5 rose from 16.1% to 20.6% over the past 2 weeks.

EG.5 is the most prevalent Omicron variant that carries the F456L mutation in the spike protein, and countries reporting rising cases are also reporting rising EG.5 proportions, partly due to its higher growth rate and partly due to other factors, including summer gatherings and waning population immunity.

Proportions for other subvariants also rose over the past 2 weeks, including FL.1.5.1 and XBB.1.16.6, both of which also carry the F456L mutation. Yesterday the European Centre for Disease Prevention and Control added EG.5 and other viruses that carry F456L as variants of interest (VOI) due to rising transmission in Europe and other world regions.

UK reports BA.2.86 cases, as Denmark reports third detection

In other virus developments, a UK scientist today reported the first BA.2.86 detection from the country. Luke Blagdon Snell, MD, a research fellow at King's College London, said on Twitter that the patient, whose symptoms began on August 13 and who contracted the virus locally, is from London and is hospitalized.

The United Kingdom is the fourth country to report BA.2.86, alongside Israel, Denmark, and the United States.

In a related development, Denmark's Statens Serum Institute (SSI) reported one more BA.2.86 detection, raising its total to three. In a statement, SSI said the three cases are from different parts of the country and don't appear to be linked to each other.

Morten Rasmussen, PhD, senior researcher at SSI, said, "It is unusual for corona to change so significantly and develop 30 new mutations. The last time we saw such a big change was when Omicron appeared."

SSI said earlier this week that efforts are under way to culture and characterize the virus. Tyra Grove Krause, MD, PhD, SSI's executive vice president for epidemiologic infectious disease preparedness, said so far there's no sign that the infections are more severe. All three patients have symptoms that are typical for COVID-19 illness.

The World Health Organization (WHO) yesterday added BA.2.86 as a variant under monitoring, and the CDC yesterday on Twitter said it is tracking the lineage. "CDC is gathering more information and will share more about this lineage as we learn it."

Global COVID trends

In other COVID developments, the WHO said in its latest weekly COVID snapshot that cases and deaths, though not reliable indicators, decreased over the past month, except in the Western Pacific region, where South Korea has experience rising activity.

Hospitalizations and intensive care unit (ICU) admissions provide more solid data, though few countries reliably report their numbers. Of the 17 that regularly report hospitalizations, 6 saw rises of 30% or more over the past month: Bangladesh, Kyrgyzstan, Greece, Malta, the United States, and Mexico. Of the few that routinely report ICU numbers, only two had increase of 20% or more over the past month: Latvia and Greece.

XBB.1.16 and EG.5 are the most common variants and at roughly equal proportions, with EG.5 doubling since late June and early July and the virus now reported in 50 countries.

Moderna sizes up vaccine vs new variants

Meanwhile, Moderna said yesterday that preliminary clinical trial findings suggest that its updated COVID vaccine prompts a significant rise in neutralizing antibodies against EG.5 and FL.5.1 variants, suggesting that it may target strains expected to circulate during vaccination season.

The company has submitted its updated vaccine for approval by the US Food and Drug Administration, the European Medicines Agency, and other regulatory bodies.

It is unusual for corona to change so significantly and develop 30 new mutations. The last time we saw such a big change was when Omicron appeared

Tyra Grove Krause, MD, PhD, SSI's executive vice president for epidemiologic infectious disease preparedness

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