Eight hundred ninety is the kind of number that sounds small until you remember it represents individual human beings who met a rare pathogen in the wrong place at the wrong time. The U.S. Centers for Disease Control and Prevention (CDC) states on its “Reported Cases of Hantavirus Disease” page dated 23 April 2026 that, as of the end of 2023, 890 cases of hantavirus disease were reported in the United States since surveillance began in 1993, and that these were all laboratory-confirmed cases including hantavirus pulmonary syndrome (HPS) and non-pulmonary hantavirus infection. CDC also explains that surveillance began during the 1993 Four Corners outbreak, that HPS became nationally notifiable in 1995, and that reporting expanded after 2014 so that non-pulmonary infections could be captured starting in 2015. If you came here for one headline figure, you now have it with the same qualifiers CDC prints.
Cumulative laboratory-confirmed U.S. cases (national surveillance)
CDC’s reported cases page is where the agency summarizes the long national arc in plain language and maps. That page is not a substitute for reading footnotes when you compare years, because surveillance systems evolve. The expansion to capture non-pulmonary infections after 2014 is a concrete example: it can change what gets counted even when rodent ecology looks similar from one season to the next.
For the historical narrative behind 1993 recognition, see this site’s History page, which cites CDC MMWR and Emerging Infectious Diseases references. This piece sticks to what CDC’s data and surveillance pages say today.
Case definitions and why “confirmed” is a surveillance term
CDC’s “Hantavirus Case Definition and Reporting” page dated 8 May 2026 explains that hantavirus disease is nationally notifiable and that NNDSS includes linked case definitions for HPS and for non-HPS hantavirus infection. CDC explicitly warns that surveillance case definitions help officials classify and count cases consistently; they are not instructions for clinicians diagnosing an individual patient. That distinction is what keeps internet arguments about “overcounting” or “undercounting” from turning into nonsense. A clinician treats a person. A surveillance officer builds a comparable numerator across states.
If you need the structural reporting explanation without cumulative totals, this site also hosts How hantavirus disease is reported in the United States.
Weekly and annual tables (NNDSS)
CDC states on its surveillance overview that CDC publishes weekly and annual surveillance data for hantavirus cases in NNDSS notifiable infectious disease data tables, and that aggregated data from optional case report forms appear on the reported cases page. That means “current week” counts can look different from the long-running cumulative map because they answer a different surveillance question. If you are building a chart, pick one product, label it honestly, and do not splice weeks together without checking how late reporting works in your state of interest.
May 2026 Andes virus cruise cluster: what CDC adds
CDC’s “Hantavirus: Current Situation” page dated 8 May 2026 describes CDC’s response to an Andes virus outbreak linked to a cruise ship in the Atlantic, reported on 2 May 2026. The same page states that, to date, no cases of Andes virus have been reported in the United States as a result of this outbreak, and that overall risk to travelers and the American public remains extremely low. CDC also notes work with the U.S. State Department and state health departments for passengers who disembarked before the outbreak was recognized. That ship cluster is a different story from the 1993-style rodent exposure narrative most U.S. prevention pages emphasize, which is why CDC gave it a dedicated situation page instead of burying it in a footnote.
Prevention and clinical urgency
Case counts do not replace exposure avoidance and early care. For step-by-step prevention aligned to CDC and WHO themes, use this site’s How to stay safe guide and CDC’s own prevention and clinical pages linked below.
Research note
This summary was written from the CDC pages below on 11 May 2026. CDC updates surveillance pages after publication; confirm numbers and wording on the live site before you rely on them for legal, travel, or medical decisions.
Frequently asked questions
How many laboratory-confirmed U.S. hantavirus cases had CDC reported through 2023?
CDC’s “Reported Cases of Hantavirus Disease” page dated 23 April 2026 states that, as of the end of 2023, 890 cases were reported in the United States since surveillance began in 1993, and that these were all laboratory-confirmed cases including HPS and non-pulmonary hantavirus infection.
Why did the surveillance system start in 1993?
CDC explains that surveillance began during the 1993 Four Corners outbreak, that HPS became nationally notifiable in 1995, and that reporting expanded after 2014 so non-pulmonary infections could be captured starting in 2015.
Is a surveillance “confirmed” case the same as my doctor saying I am confirmed?
Not necessarily. CDC states that surveillance case definitions help public health officials classify and count cases consistently, and that they are not written as instructions for clinicians diagnosing an individual patient.
What did CDC say about the May 2026 Atlantic cruise cluster for the United States?
CDC’s “Hantavirus: Current Situation” page dated 8 May 2026 states that CDC responded to an Andes virus outbreak linked to a cruise ship reported on 2 May 2026, that no U.S. Andes cases had been attributed to that outbreak as of that page date, and that overall risk to travelers and the American public remains extremely low.