Outbreak Outlook - National - March 11

Finally a break in the clouds

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Respiratory Diseases

ILI

After a series of stagnant weeks, there was finally some movement this week, as influenza-like illness (ILI) rates marginally decreased from 4.4% to 4.1%. The national baseline that marks the start and end of flu season is 2.9%, so we are still not close to declaring the end of this flu season. And while there has been a slight decline in emergency department visits and hospitalizations due to influenza, the pace of this decrease is gradual. We do not seem to be on the fast track out of the flu season, but at least we are headed in the right direction.

By age: Most of the progress in the overall numbers is thanks to the 5-24 age group, which saw significant improvement at last report, falling from 7.1% to 6.6%. The beleaguered 0-4 age group was not so lucky; ILI is still over 10%. Older age groups remained about the same at 2-4%. 

Emergency department data looks similar, with marked improvements in the 5-17 age group, and less improvement for everyone else.

By region: Twenty states are still in the high or very high categories. States most affected include New Mexico, Nebraska, Michigan, Ohio and Washington, D.C. The Western census region is in the best shape with most states in the low or moderate categories. The Midwest continues to struggle to turn the corner — outpatient ILI rose slightly across the region again this week, putting it in an unhappy first place.

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COVID-19

Covid-19 metrics across the country are still showing signs of improvement. Emergency department visits for Covid-19 are steadily decreasing in all age groups, including those over 65, who are at a higher risk for severe illness. New weekly hospitalizations are also declining, with the national rate slightly lower than what we saw this time last year. Overall, I think we are on the right track.

Test positivity rates have also dropped to 6.5%. Although testing is less common these days, I still use test data as a secondary indicator. Additionally, wastewater surveillance indicates a decrease in SARS-CoV-2 levels nationwide, with significant progress observed in the Southern region where both COVID-19 activity and wastewater concentrations were previously high.

These improvements are seen in all four regions of the country, including the South, which had a late resurgence following the New Year peak. The Western region is again in best shape, with new weekly hospitalizations nearing 3 per 100,000.

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Stomach Bugs

Norovirus activity continues to accelerate across the country, with test positivity now exceeding 15%. For context, last year’s peak occurred in mid-March at around 16%, and the year before was similar. I think this year will likely be the same. Hang in there for a few more weeks!

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Food recalls

The following foods are being recalled because they are contaminated. Please check your cupboards and throw out any of these items:

New

• Multiple brands of cinnamon sold at discount stores, for lead contamination. The best resource I found to quickly survey affected products is here. You can also view the FDA’s list here.

• Raw Farm brand cheddar cheese (more info)

• Sargento Foods shredded cheese. This recall affects food service customers and does not include Sargento-branded retail products. (more info)

Previously reported:

• Roland brand Tahini (more info)

• Trader Joe’s Chicken Soup Dumplings (more info)

• A big recall of Queso Fresco and Cotija Cheese is affecting numerous consumer products: (more info)

• Robitussin Honey CF Max cough syrup products (more info)

• Tons of different granola and oatmeal products from Quaker (more info).

• If you have food allergies, you may wish to review these FDA safety alerts and USDA alerts for foods with undeclared allergens.

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In other news

• A Spanish-led research team has confirmed the presence of the highly pathogenic H5 avian flu on Antarctica's mainland for the first time. This discovery at the Gabriel de Castilla research base on Deception Island follows the virus's detection in Antarctic penguins and other birds and sea mammals in sub-Antarctic areas. The virus was found in two dead skuas (a kind of bird) near Argentina's Primavera base, highlighting its southward spread and raising concerns about the impact on Antarctica's previously unexposed wildlife. 

• I thought this was a helpful FYI: “For adults 60 and older who have not already received an RSV vaccine and decide with their healthcare provider to get one, CDC encourages healthcare providers to maximize the benefit of RSV vaccination by giving them their RSV vaccine in late summer or early fall, just prior to the RSV season.”

  • In other words, you may want to consider getting your RSV vaccine before you’re flu shot, because the seasons have different start times.

• A preprint article (meaning it has not yet undergone peer review) about mpox in the Democratic Republic of Congo caught my eye. The authors found that most cases they investigated were acquired through heterosexual and household contact, a departure from the primarily MSM-driven spread observed in the 2022 epidemic of mpox. The DRC outbreak is also notable because it at least some cases are clade I, which is thought to have a higher mortality rate. The 2022 epidemic was clade IIb. I’ll be watching this outbreak in the weeks to come.

Photo by Daniel Seßler on Unsplash