This page answers one question every week: what is actually going around in the United States right now, according to the surveillance data, not the headlines. It is rewritten each week from the same feeds Vira reads. Where the data is thin or late, it says so.
The short version
Rising this week: West Nile virus (11 cases, up from an average of 3.8), Mumps (3 cases, up from an average of 0.2).
Falling: E. coli (STEC), Tuberculosis, Hepatitis A.
Reportable diseases, CDC week ending September 7, 2026
Counts are what state health departments reported to the CDC's National Notifiable Diseases Surveillance System for the week. They run about three weeks behind the calendar and are revised for months, so read the direction more than the number. The trend compares the week with the average of the four weeks before it.
| Disease | This week | 4-week avg | Trend | Most cases |
|---|---|---|---|---|
| West Nile virus | 11 | 3.8 | rising | Virginia (3), Nebraska (2), Texas (2) |
| Mumps | 3 | 0.2 | rising | Indiana (1), New York (1), Ohio (1) |
| Campylobacter | 1,057 | 1,000 | steady | Florida (135), California (115), New York City (86) |
| Salmonella | 941 | 942 | steady | Florida (268), South Carolina (89), New York (71) |
| Shigella | 202 | 200 | steady | New York City (42), Florida (33), New York (20) |
| Giardiasis | 185 | 206 | steady | California (26), New York City (24), Florida (20) |
| Cryptosporidiosis | 174 | 212 | steady | California (23), Georgia (22), Ohio (17) |
| E. coli (STEC) | 165 | 235 | falling | New York (34), Florida (23), New York City (21) |
| Measles | 125 | 125 | steady | Pennsylvania (85), Ohio (20), New York (12) |
| Legionnaires' disease | 123 | 109 | steady | Ohio (27), New York (22), Florida (15) |
| Whooping cough (pertussis) | 76 | 73 | steady | Pennsylvania (13), Virginia (9), Ohio (9) |
| Invasive pneumococcal disease | 75 | 74 | steady | Florida (14), Ohio (13), Arkansas (6) |
| Tuberculosis | 56 | 75 | falling | New York City (9), California (7), New Jersey (6) |
| Chickenpox (varicella) | 48 | 43 | steady | Florida (15), Ohio (14), Pennsylvania (5) |
| Hepatitis A | 4 | 6.2 | falling | Pennsylvania (1), Florida (1), Ohio (1) |
Flu-like illness, week ending September 6, 2026
The share of doctor visits for influenza-like illness, by CDC region. The national baseline that marks the start of flu season is about 3 percent; anything under 2 is a quiet week.
National: 1.5% of visits, from 1.4% the week before.
| Region | ILI visits |
|---|---|
| Southwest and Pacific | 2.3% |
| Southeast | 1.8% |
| South Central | 1.8% |
| NY, NJ, PR, VI | 1.4% |
| Mid-Atlantic | 1.4% |
| Northwest | 1.1% |
| Mountain | 1.1% |
| New England | 0.9% |
| Central Plains | 0.9% |
| Great Lakes | 0.8% |
Season posts: Flu season 2026 to 2027 and RSV season 2026 to 2027.
Stomach bugs
Norovirus is the most searched illness on this site and the one the CDC does not count: it is not a reportable disease, so there is no weekly state table for it. What we can see is the reportable gastrointestinal diseases in the table above (Salmonella, E. coli, Shigella, Campylobacter) and the outbreak reports in the news. The season view is on the norovirus fall 2026 page.
In the news this week
US outbreak reporting picked up by our feeds in the last seven days. A headline is a signal of attention, not a case count.
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Measles, Imported (Bangladesh): Warning over Bangladesh's dengue outbreak after deadliest month (Oct 1)
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Measles, Imported (Pennsylvania): Pennsylvania Records a Fifth Measles Death as the Nation Endures Its Worst Year Since 1991 (Oct 1)
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Measles, Imported: CDC updates measles toll, now counts 2 deaths (Sep 30)
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Measles, Imported (Pennsylvania): CDC reports second measles death in US while excluding Pennsylvania deaths (Sep 30)
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Dengue virus infections, Dengue (Florida): Dengue fever outbreak prompts Florida counties to declare state of emergency (Sep 29)
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E. Coli (California): E. coli outbreak tied to raw milk cheese hits California with multiple cases (Sep 27)
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Ebola: U.S. pledges an additional $267 million to contain fast-spreading Ebola (Sep 26)
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Measles, Imported (Illinois): Illinois measles cases hit 23 in 2026, most from Douglas, Moultrie counties outbreak (Sep 26)
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E. Coli (Florida): Publix sued after Florida woman's death blamed on E. coli-tainted blueberries (Sep 25)
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Measles, Imported: Trump's FDA nominee says MMR shot is 'safe and effective' at Senate hearing (Sep 25)
How to use this
A rising line in the table is a reason to pay attention where you live, not a reason to worry. The counts are statewide; your county can be quiet while the state number climbs. If you want to know when something changes in your own city rather than checking back here, that is what Vira does: she watches the same feeds for the places you name and texts you only when something moves. Join the early access list.
Data: CDC NNDSS weekly tables (week ending September 7, 2026), CDC ILINet, and Virus Watcher outbreak feeds. Updated weekly. Past weeks are archived in Virus Watcher Weekly.