Respiratory Diseases

Influenza-like illness

Influenza-like illness remains low in most areas of the country, but activity is picking up a bit as we head deeper into the winter months. Around 2.5% of visits to the doctor were for fever and cough or sore throat, up from 2.4% the week prior. We are still likely several weeks away from crossing the 3% threshold that marks the beginning of flu season.

Source: CDC

All states remain in the minimal or low categories for outpatient ILI, but the Southern states and and parts of the West are seeing increases in wastewater concentration, which suggests that activity is increasing (as expected this time of year).

Young children are experiencing the most flu-like illness, as always. They saw a jump from 7.5% to 8.1% outpatient ILI. For comparison, last year peaked at 15.5% around the New Year. Older age groups saw less dramatic increases, with the 5-24 age group rising from 3.8% to 4.0%. Adult age groups remain below 2%.

It is too early to determine how well this year’s flu vaccine matches the circulating strains. However, so far most subtyped specimens are either H1N1 or H3N2—the strains that have been predominant in recent years.

COVID-19

The respite continues. Covid-19 wastewater activity is low and declining in most areas of the country.

Although the Midwest leads the country in wastewater activity, its activity remains low and stable.

Wastewater activity is low in the West and minimal in the South and Northeast. Only one state in the country reported very high wastewater activity last week: New Mexico.

Trips to the emergency department for Covid-19 remain minimal, accounting for just 0.5% of all emergency department visits in the past week. The number of people hospitalized due to the virus also declined again, to the low rate of 1.0 hospitalizations per 100,000 people.

RSV & Other Bugs

RSV: RSV activity is still low across the country, but there are some increases in the South, with hospitalizations and wastewater concentration beginning to pick up.

Activity in the rest of the country is minimal, but early indicators (e.g., test positivity) are rising, and so I do expect the weeks ahead to bring more intense transmission.

Other bugs: A bunch of other viruses that cause respiratory infections and cold/flu-like symptoms are increasing.

Adenoviruses and human coronaviruses are both on an upswing, but remain at middling levels.
Parainfluenza is fairly elevated, with 5.7% test positivity. In the past couple years, when it has gone through a period of higher spread, it tends to peak around 7-9% test positivity.
Rhinoviruses/enteroviruses have at quite-elevated 20-30% test positivity for the past month, and this week increased a bit again, to 28.5%.
After a period where activity seemed to be declining, Mycoplasma pneumoniae activity is again rising. This has been one of the most active years for M pneumo in recent years, so I am sorry to see it continue to intensify.

Stomach Bugs

Norovirus is fairly high at 12.4% test positivity and increasing. Test positivity has increased about 2.4x since the low it hit in early September. This is the time of year we expect norovirus to be more active, so I don’t expect to see low rates return for a few months. Rates are highest in the South, followed by the West, and Midwest; they remain low in the Northeast.

Food recalls

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

New:

Bagged carrots, full size and baby, sold at multiple retailers (more info)

Previously reported:

Soft ripened cheeses, including brie, sold under multiple brand names, including Aldi, La Bonne Vie, and Glenview Farms (more info)
- Prepackaged turkey sandwiches with spreadable brie sold under multiple brand names (more info)
Ready-to-eat poultry and meat products sold by Yu Shang Food, including pork belly, beef shank, and whole chicken (more info)
Waffles and pancakes - many flavors and styles - sold under a very large variety of brand names, including numerous store brands, including 365 Organic, Best Choice, Good & Gather, Harris Teeter, H-E-B, Nature’s Promise, Publix, Trader Joe’s and Wegmans.
- Given the size of this recall, if you have any variety of frozen/toaster waffles, Belgian waffles or pancakes in your freezer that you bought in the US or Canada, check this list. (more info)
If you have food allergies, you may wish to review these FDA safety alerts and USDA alerts for foods with undeclared allergens.

In other news

The California Department of Public Health has confirmed the first U.S. case of clade I mpox, linked to an ongoing outbreak in Central and Eastern Africa. The case involves a traveler from Eastern Africa, now isolating at home with improving symptoms. Unlike clade IIb, which was responsible for the 2022 epidemic, clade Ib spreads through household and heterosexual contact. For reference, a recent importation of clade Ib into the United Kingdom led to three household members becoming infected, but no reported spread outside the household.
President-elect Donald Trump plans to nominate Robert F. Kennedy Jr. as Secretary of Health and Human Services. Kennedy, a prominent anti-vaccine activist and critic of institutions like the FDA, will require Senate confirmation unless the Senate allows the president-elect to make recess appointments. Other key health positions, such as CDC Director, NIH Director, and FDA Commissioner, have not yet been announced. Those nominees will also require Senate confirmation.
The E. coli outbreak linked to McDonald’s Quarter Pounders has grown to 104 cases across 14 states, with 34 hospitalizations, four cases of serious kidney complications, and one death. Health officials and McDonald’s identified slivered onions from Taylor Farms as the likely source, prompting a recall on October 22. The CDC now considers the food safety risk resolved, and McDonald’s has resumed serving Quarter Pounders with onions from a new supplier. Colorado, Montana, and Nebraska reported the highest case numbers. The outbreak includes cases dating back to September.

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