Outbreak Outlook - National - October 16

RSV activity is rising quickly

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Respiratory diseases

Influenza-like illness

In the week ending October 7, influenza-like illness (ILI) remained about the same. Around 2.2% of visits to the doctor were for fever and cough or sore throat, up from 2.1% the week prior. We are below the level of ILI that we saw at this time last year, but slightly above where we had been at this point in the four years prior.

At the national level, ILI in the youngest children rose again this week to 7.7%, up from 7.1% the week prior. For the 5-24 age group, the rate rose slightly from 3.3% to 3.5%. Older age groups remain below 2%. If you have young children at home, there may be sick days ahead.

Washington D.C. and New York City were both in the “high” categories for the last two reports. They are now back down to the “low” categories. I’m not sure what explains this drop-off, but it’s good news so I’ll take it. Alaska is in the “moderate” category. The rest of the country is “low” or “minimal.”

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Covid-19

Covid-19 activity continues to fall around the country. The number of new hospitalizations fell again this week, as did test positivity. For comparison, our most recent peak was about 20,600 hospitalizations; we are now at 18,100. Although I hope we will continue to see declines, activity commonly remains elevated through the autumn and winter months.

The number of deaths per week is around 1,200 (with some uncertainty because of lags in data reporting). At this time last year, there were around 2,500 weekly deaths.

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RSV

RSV activity rose sharply again this week. The season has definitely started. PCR test positivity was 3.5% nationally, up from 2.6% last week. These increases are almost entirely driven by rapid increases in the Southern region, where PCR test positivity is now nearly 10%. RSV activity in the South is definitely notable, so if you live in the area, please be cautious. The other regions of the country are calmer, for now.

This is the first year that RSV shots are available for older adults, infants, and pregnant women, so I hope the availability of these products helps reduce severe illness among these vulnerable groups.

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Others

I'm monitoring several other respiratory viruses. Here's the current status:

• Seasonal coronavirus, human metapneumovirus, and adenovirus all seem to be under control, with no concerning increases.

• However, rhinovirus/enterovirus, which can cause the common cold, is on the rise. So, it's likely that we'll see more stuffy noses.

• I'm also keeping an eye on parainfluenza, which can lead to influenza-like symptoms. There might be a slight increase in cases, but I'm not completely sure about it yet.

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Stomach bugs

Norovirus

• Norovirus activity is generally on the decline across most parts of the country, which is reassuring.

• However, there's a notable exception in the Midwest region. In this area, the percent positivity rate has increased significantly, now standing at over 11%. This is a considerable jump from a recent low of 6.3%.

• Meanwhile, in the rest of the country, norovirus positivity rates remain relatively low, consistently below 4%.

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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 this week:

• Ready-to-eat ham produced by Sunnyvalley Smoked Meats (more info)

Previously reported:

• Ion and Restore brands Sinus Spray (more info)

• Organic Chicken and Beef Broth sold at Costco and Whole Foods (more info)

• Whole cantaloupes sold by Eagle Produce (more info)

• Not Fried Chicken sold by Life Raft Treats (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

• In a recent update on a Nipah virus outbreak in Kerala, authorities have confirmed that there hasn’t been a third generation of cases, meaning the virus does not appear to be spreading from person to person beyond the initial cluster. Nipah virus is a zoonotic pathogen originating from fruit bats. It is known for causing severe respiratory illnesses and encephalitis in humans. Six cases were diagnosed last month; no new cases have been reported since September 15.

• The U.S. Department of Agriculture has confirmed cases of influenza H5N1 in three adult harbor seals in Puget Sound. These findings mark the first report of H5N1 in marine mammals on the West Coast, following an outbreak that affected seabirds and led to the deaths of about 1,700 birds.

Photo by Alisa Anton on Unsplash