Outbreak Outlook - National - February 1
Respiratory Diseases
Influenza-like illness
After several weeks of declining activity, flu has picked back up. Outpatient influenza-like illness rose to 4.7%. However, while this is an increase over last week, this remains far below the peak several weeks ago, of 8.3%. Similarly ED visits for influenza, also rebounded slightly this past week to 3.4% nationally.
This rise seems to be due in part to an increase in influenza B, while influenza A is holding stable at elevated rates. That said, influenza A still accounts for the majority of flu cases: influenza A accounted for 87% of clinical lab samples and 94% of public health lab data this past week.
Increased activity in school-age children is also driving up overall rates. Those aged 5-24 are seeing the clearest increase, with 8.1% of doctor’s visits due to ILI. Rates have also increased slightly for those aged 0-4 (to 12.4%). All other age groups continue to report declines in outpatient ILI.
Looking ahead, we often see that a rise in kids, as we’re seeing now, is soon followed by an expansion into other age groups. My current hypothesis is that the severe weather that much of the country saw last week will interrupt that pattern, hopefully cutting off chains of transmission and stopping the rise.
Hospitalizations have fallen substantially over the past month, from 12.9 to 2.4 hospitalizations per 100,000 people.
COVID-19
Covid-19 wastewater activity continues to decline from its national peak at the beginning of January. Overall activity is moderate.
In the Midwest, wastewater activity is very high, rebounding slightly in the past week. Wastewater concentration also rebounded a bit in the South, but activity there is low. Activity continues to decline steadily in the Northeast, and has fallen to moderate levels. Activity is low but increased a bit this past week in the West.
Test positivity has been holding roughly steady the past few weeks, at a little over 5%, but ED visits continue to gently decline. Nationally, ED visits are at about 0.7%. They remain highest in the Midwest and lowest in the West.
Severe illness is low, at about 0.8 hospitalizations per 100,000 people, or less than half of what it was about a month ago.
RSV & Other Bugs
RSV: RSV has been on a sneaky, gradual increase for the past several months and we are finally hitting quite elevated levels, with the epidemic estimated to be growing in a little less than half the country. Test positivity is up to 6.3%, its highest so far this season.
Nationally, about 0.5% of ED visits are due to RSV. ED visits continue to be highest in the South (~0.7%) and lowest in the West (~0.4%).
Hospitalizations have decreased a bit over the past few weeks, to about 1.5 hospitalizations per 100,000 people nationally.
Other Bugs: My usual data source did not update this past week, but wastewater data suggests that human metapneumovirus — a common cause of runny noses, sore throats and coughing — is very high right now.
Norovirus
Nationally, norovirus wastewater activity has decreased rapidly in the past week, dropping from fairly elevated activity down into more moderate activity.
This seems to be driven primarily by a sharp decrease in the South over the past few days, from high to moderate activity. In addition, in the Northeast, norovirus activity is high, but has been on a decreasing trend for the past several weeks.
In contrast, in the Midwest, activity has sharply increased in the past few days, and is quite high (though it remains well below the extremely high rates we saw last year around this time). And in the West, activity is holding roughly steady at high levels.
(My primary norovirus data source from the CDC with test positivity numbers didn’t update this week, so I am relying on wastewater surveillance data.)
Food recalls
The following foods are being recalled because they are contaminated. Please check your cupboards and throw out any of these items:
New:
Gerber Arrowroot biscuits (more info)
IKM cookware products (primarily sold in California grocery stores) due to potential lead contamination (more info)
Organic chia seeds sold by Navitas Organics (more info)
Live it Up Super Greens powders and packets in Original and Wild Berry flavors (more info)
Canned yellowfin tuna in olive oil under the Genova brand name (more info)
Previously Reported:
Suzanna’s Kitchen Recalls Ready-To-Eat Grilled Chicken Breast Fillet (more info)
Super Greens supplement powder (more info)
Spring & Mulberry chocolate bars (more info)
Pecorino cheese from various brands, including Boar’s Head and Members Mark (more info)
Sea Moss Gel Superfood (more info)
Klong Kone Shrimp Paste, sold exclusively at Golden Land in Des Moines, Iowa and Terri Lee Oriental Groceries in Maywood, New Jersey (more info)
Primavera Nuevo tamales, various flavors (more info)
There is a big recall of hundreds of products — from Airhead candies to meat to Splenda packets — that passed through a single distributor and were sold to over 50 stores, primarily in Minnesota and Indiana. I strongly urge you to check out the list of stores (here) and if you’ve shopped at one of them recently, check out the much longer list of items that are being recalled (here)
In other news
Government shutdown plans. Congress has failed to pass a comprehensive budget, triggering a partial government shutdown that includes the Department of Health and Human Services. Shutdowns typically mean that CDC is not able to share disease surveillance data. If that happens, we will go state by state to collect the data by hand, which would be the third time in 13 months we’ve had to make this pivot. In that case, I will not be sending out regional editions, because my priority is making public health data widely accessible during the gap. Instead, I will send out a single edition with data briefly summarized for every state. Thank you to paid subscribers for supporting our work and making this coverage possible.
Salmonella outbreak in Moringa Leaf Powder supplements expands. As I’ve reported in the Food Recalls section over the past several weeks, a few different brands of ‘super greens’ dietary powders and capsules have been recalled due to potential Salmonella contamination. As of January 29, the CDC has identified 65 people in 28 states with a related outbreak strain of Salmonella, the vast majority of whom (88%) reported consuming one or more moringa leaf powder products. The products mentioned by affected individuals share a common manufacturer, and further testing has confirmed that moringa leaf powder is the source of the contamination in this outbreak.
Nipah virus outbreak in India. Two cases of Nipah have been reported to the World Health Organization (WHO), both located in West Bengal State. Both infected individuals are healthcare workers, but it is unclear whether they contracted the virus while performing their duties. Nipah is rare, and is typically acquired through contact with infected animals (often bats) or food contaminated by infected animals. It can also spread person-to-person, through close contact. Nipah can cause severe illness, and has had a reported case fatality rate of between 40-75%. There are no approved medications to treat Nipah, but early access to supportive care can increase the chances of survival. The WHO assesses the risk of additional cases within and around West Bengal as moderate. International risk is considered low.
United States pressuring Gavi to remove certain vaccines to maintain funding. The Department of Health and Human Services has requested that Gavi phase-out all vaccines containing thimerosal, a preservative that helps keep vaccines from being contaminated with microbes and threatened to withhold funding if this is not done. Gavi provides vaccinations to children around the world, and the US has traditionally been one of its primary financial supporters. For years, anti-vaccine activists have claimed, without evidence, that thimerosal is causes developmental delays in children. Numerous scientific studies have not found any link between thimerosal and developmental delays.
Coming soon. My new resource, FOI Clinical, will be launching February 11. FOI Clinical is designed for clinicians. It will cover reportable diseases, emerging outbreaks, and infectious-disease related policy changes that affect patient care. Learn more at foiclinical.com.
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Thank you so much! 💕
I too have seen reports that the CDC surveillance functions are being disrupted and states are encouraged to decide what to do. Vaccine preorders from state and regional consortiums or insurance carriers should be looked into but funds? People who deal in shelf stable widgets just do not get the whole “capacity” to respond that is required for contagion and emerging pathogens. Surveillance and early detection? It’s a political nightmare. They learned nothing from the excess death from SARS-2 except how to shuffle the numbers and how to attack the stressed health care system as lean and mean capacity hit a prolonged siege of airborne contagious patients. Airborne contagious patients… I will let the duality stand.