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Respiratory Diseases
ILI
Not as much progress this week as I had hoped. The percentage of visits to the doctor that were for fever and cough or sore throat (known as ILI) fell only slightly from 4.4% to 4.3% during the week ending January 27. Plus, influenza test positivity actually rose, and influenza hospitalizations remained basically flat. Taken together, this means that influenza is definitely still active, so don’t abandon caution yet.
By age: I have bad news for the school age kids (and their parents, teachers, etc.). Influenza-like illness actually rose in the 5-24 age group, with outpatient ILI rising from 6.4% to 6.6%. Emergency department visits for influenza also remained elevated in the 5-17 age group.
The other age groups, including the 0-4 group, all saw decreases in outpatient ILI and emergency department visits.
By region: The South is still in the thick of things, with most states in the region falling in the high category. On the other hand, the Midwest continues to look quite good — activity has increased there slightly, but the current levels of activity are so low that the overall picture is still good. The West and Northeast are somewhere in the middle, with most states in the low or moderate categories.
COVID-19
In better news, Covid-19 activity is still declining. The percentage of emergency department visits that are for Covid-19 for the last month, bringing us to levels similar to what we saw at the end of November.
One caveat: ER visits in the 5-17 year old age group is increasing for Covid-19, too! We are seeing this for influenza too (as above). I’m not sure what is behind this odd trend, but be careful out there if you have a school age kid in your life. Also, sometimes we see bumps first in children and later in adults, which I always imagine to be kids getting their parents sick. That’s something I’ll be looking for in the data.
Other indicators: Back to the birds eye view, the number of new weekly hospitalizations is declining, and wastewater data has begun to level out. SARS-CoV-2 concentration in wastewater peaked around the new year and declined rapidly for about a month. I did notice that improvement in wastewater concentration is slowing, meaning it’s not dropping as fast as it was.
By region: Covid-19 activity is decreasing in all four regions of the country. The Northeast has seen in the most progress, but it remains the most affected area. The Western region is in the best shape, with weekly hospitalization rates nearing 6 per 100,000. For reference, that is similar to this summer’s peak (at the national level).
RSV
RSV activity continues to fall following the early December peak. Test positivity is now just under 6% nationally. Hospitalizations are also down in all age groups, including in the heavily-affected 0-4 year olds.
Around 21% of adults aged 60+ received the new RSV vaccine. That number held mostly stable through January.
Other respiratory
Seasonal coronavirus activity is way up. There are four seasonal coronaviruses, and they cause cold-like symptoms. I suspect activity will peak this month.
Surveillance for metapneumovirus is not very good, but I think it’s picking up a little bit. Metapneumovirus typically presents with coughing, fever, and nasal congestion, and its activity peaks in the late winter and spring months.
Stomach Bugs
As I expected, norovirus bounced back from a brief dip and is now rising again. Test positivity nationally is now at 13.1%. It’s been in the 10-13% range since mid-December. I expect activity will continue to pick up until early spring.
Test positivity is not a perfect measure, because most people who have GI symptoms never get tested to determine which bug is making them sick. Still, I find that it’s directionally correct, meaning that when test positivity rates increase, overall activity is increasing as well.
Remember to keep some rehydration fluids handy. If you get sick, you’re not going to be able to run to the store to restock.
Food recalls
The following foods are being recalled because they are contaminated. Please check your cupboards and throw out any of these items:
New
Previously reported:
Robitussin Honey CF Max cough syrup products (more info)
Brightfarm Spinach and Salad Kits (more info)
Charcuterie meats sold by Fratelli Beretta and, newly, Busseto (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.
In other news
Researchers have discovered a new group of virus-like elements, named "Obelisks," in the human microbiome. These elements have circular RNA genomes. They are unique for their structure and a novel protein they encode. This finding of Obelisks in our gut and oral microbiomes may open up new avenues for exploring microbial functions and their implications on human health.
Chinese health authorities have reported the first known case of a human infected with a H10N5 flu virus, found in a 63-year-old woman from Anhui province. She was also infected with the H3N2 seasonal flu. The patient died in December. The H10N5 virus is thought to be of avian origin, suggests cross-species transmission. It is not considered to have a high risk of widespread human infection. Investigations into the patient’s close contacts revealed no further cases.
Thanks for the summaries. Correlates with my observations, so I may be doing something right.