Outbreak Outlook - October 21

Covid-19 and ILI are low, stomach bugs are up

Oct 21, 2024

Programming Note: Regional editions start next week! I will continue to publish a national weekly update, which will remain free to read. The change is that paid subscribers will have the option to receive additional updates tailored to the Northeast, Midwest, South, and Western regions. To learn more, click here.

Influenza-like Illness

We are now in the new influenza season (2024-2025). Outpatient visits are up slightly, with 2.1% of visits to the doctor are for fever and cough or sore throat, up from 2.0% last week.

By age: Young children saw a sizeable jump, from 6.1% to 6.4%. School age children are up too, from 3.2% to 3.4%. I know my household was hit with an unpleasant respiratory virus recently.

By state: All states are reporting low or minimal levels of activity, as measured by outpatient visits. Wastewater concentration of influenza A is also low or minimal in all states.

Covid-19

Covid-19 has calmed down in most of the country - but it may be picking up in the Northeast. Wastewater activity is low nationally and is fairly similar across all four regions (highest in the Northeast).

Emergency department visits are minimal - 0.7% of all visits last week - and decreased again this past week. Hospitalizations have decreased to low levels: 1.5 hospitalizations per 100,000 population.

Northeastern Region

Wastewater activity is low, but ticked up this past week. Concentration is now slightly above the national average. However, ED visits and hospitalizations have both continued to decline following the late summer wave.

Massachusetts, New Jersey and Rhode Island are doing very well. These states are reporting low or minimal wastewater activity.

Connecticut is doing fine. Wastewater activity remains low, and the state has seen a decline in ED visits. Hospitalizations have also decreased slightly, now standing at 2.5 per 100,000.

Maine, New Hampshire, and Vermont are experiencing similar trends. Although all three states still have high wastewater activity, but it's on a downward trajectory.

Pennsylvania's status is less clear-cut. The state is seeing moderate wastewater activity that has remained roughly stable. And New Hampshire stands out as the only state in the region where ED visits have remained stable rather than declining.

New York's situation is the most uncertain due to reporting lags. However, hospitalizations have significantly dropped from 8.7 in mid-September to 4.5 currently, though there's still room for further reduction.

Western Region

Things are calm across most of the West. Wastewater activity is low, ED visits are minimal and declining, and hospitalizations are decreasing. Wastewater activity is nearly 5x lower than it was during this summer's peak.

Nevada and Alaska are doing very well. Both states are reporting minimal levels of wastewater activity. California and Hawaii are also in good shape, with low levels of wastewater activity. California has seen substantial declines (>20%) in ED visits and a decrease in hospitalizations to 1.6 per 100,000. Hawaii has also experienced a significant drop in ED visits.

Utah, Colorado, New Mexico, Idaho, and Washington are in a similar situation. These states are seeing moderate wastewater activity. Utah and New Mexico have stable ED visits, while Idaho has seen a substantial decline. Colorado's hospitalizations have decreased to 1.5 per 100,000, and New Mexico's to 1.2 per 100,000.

Oregon and Wyoming are showing improvement. wastewater activity is still high but decreasing. Both states have seen substantial declines in ED visits. Oregon's hospitalizations have decreased to 2.2 per 100,000, which is slightly elevated compared to other states in the region.

Arizona's situation is less stable. Wastewater activity is high and has been fluctuating between high and moderate levels for several weeks, increasing again this past week. ED visits in Arizona have remained stable.

Montana has limited data available.

Southern Region

Covid-19 is quiet across much of the South, with low wastewater activity, minimal emergency department (ED) visits, and low and decreasing hospitalizations. Wastewater activity is almost as low as it was in May before the summer surge.

Texas, Florida, Mississippi, and Georgia are doing very well. These states are reporting minimal levels of wastewater activity, though Mississippi has limited coverage.

Virginia, Delaware, Washington DC, Alabama, South Carolina, Tennessee, Kentucky, West Virginia, and Louisiana are also in good shape, all reporting low wastewater activity. Tennessee's hospitalizations have held roughly steady at 1.2 per 100,000.

Maryland, North Carolina, Arkansas, and Oklahoma are showing moderate but improving or stable conditions. These states have moderate wastewater activity that is either decreasing or stable. Maryland's hospitalizations have declined to a low level of 0.9 per 100,000, while North Carolina, which just started reporting hospitalization data for the season, is at 1.2 per 100,000.

Midwest Region

Things look good for Covid-19 in the Midwest: wastewater activity is low, ED visits are minimal and declining, and hospitalizations are coming down. Wastewater activity is now almost as low as it was in the summer before the late summer surge.

Illinois is doing very well, reporting minimal levels of wastewater activity. The state has also seen a decrease in ED visits.

Wisconsin, Michigan, Ohio, Indiana, and Kansas are in good shape, all reporting low wastewater activity. Wisconsin's ED visits have remained stable. Michigan, however, has seen a slight increase in hospitalizations to 3.1 per 100,000 after several weeks of declines. While this is better than September's rate of ~5, it's still considered elevated. Indiana has experienced a decrease in ED visits.

Nebraska and South Dakota are showing moderate wastewater activity, though South Dakota has limited data available.

Minnesota presents a mixed picture. While hospitalizations have declined substantially to a low 1.5 per 100,000, wastewater activity is high and increased slightly this past week after several weeks of declines. No ED visit data were available for Minnesota.

Ohio usually reports hospitalization data but hasn't for the past couple of weeks, so there's no recent information available. North Dakota and Missouri have limited data available.

Norovirus

Norovirus just keeps going up, up, up. We have seen 6 weeks of increasing rates, and are now at 10% test positivity nationally. Rates are highest in the South, where test positivity increased again this past week to 19.3%. This is higher than at any point in the past two years for the region.

In the West, norovirus test positivity, which had been hovering between ~6-8% for the past couple months, increased this past week to 9.4%. In the Midwest, test positivity has increased to 8%, up from ~5% in August. Norovirus remains low in the Northeast at 1.7% test positivity.

RSV & Other Respiratory Infections

RSV: Test positivity is beginning to pick up, but remains quite low.

Others: As I reported last week, some common causes of cold- and flu-like symptoms are on the rise. Parainfluenza has increased again to 4% or about where it was this time last year. Adenovirus test positivity increased again this past week, though it still remains relatively low. On the plus side, rhinoviruses/enteroviruses decreased a bit this past week, down to 26% test positivity.

Food recalls

New:

Nothing new this week

Previously reported:

Large variety of ready-to-eat meat and poultry products under different brand names, including Rao’s chicken alfredo and Michael Angelo’s grilled chicken piccata with penne pasta (more info)
Enoki Mushrooms (more info)
Bistro28 and Don Pancho Meal Kits containing chicken (more info)
Happy Moose Tropical Roots and Strawberry Fields juice (more info)
L&B Lone Star Dip (more info)

In Other News

If you’re into stories of smart, high-stakes problem-solving or the history of science, check out my new book, Crisis Averted. I shares real accounts of how clever scientists have prevented disaster—and why, at times, their efforts fell short. (It is a book for a general audience, so don’t worry that it will be too technical!)

In related news, a Vermont-based reader sent me this amazing comic. It was inspired by the New York Times’ excerpt of a chapter in my book. I love hearing from readers!

H5N1 continues to be reported in poultry, dairy cows and humans in the United States.
- In California, 13 cases human cases have been reported. All are mild illnesses in farm workers.
- Just yesterday, Washington state reported 4 human cases in poultry farm workers.
- We are still waiting for the serology test results for the Mississippi cluster under investigation.
Africa's mpox outbreak continues, with over 42,000 cases and 1,100 deaths reported this year. The virus has been reported in 18 countries, including recent cases in Kenya, Zambia, and Zimbabwe. The Africa CDC's Director-General, Jean Kaseya, highlighted ongoing challenges, including cross-border transmission and outbreaks in crowded settings like prisons in Uganda and refugee camps in the DRC, where hygiene issues hinder containment efforts. Vaccination campaigns have begun in the DRC and Rwanda, with Nigeria set to start on October 22. However, only four countries have comprehensive vaccination plans, limiting broader regional coverage.
Pertussis (whooping cough) cases in the U.S. have surged to over 16,000 this year, marking the highest levels since 2014, with two confirmed deaths. The disease is most dangerous for infants, who often require hospitalization. According to CDC, “pregnant women should get a dose of Tdap during every pregnancy, preferably during the early part of the third trimester, to help protect the newborn from pertussis.”

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