You might want one headline number for confirmed hantavirus cases in the United States. CDC does publish official totals, but the figure you need depends on what you mean: the long arc since 1993, a given week in NNDSS tables, or a short statement tied to a specific event such as the May 2026 Andes virus cruise investigation.
Cumulative laboratory-confirmed U.S. cases (national surveillance)
CDC’s “Reported Cases of Hantavirus Disease” page dated 23 April 2026 states that, as of the end of 2023, 890 cases of hantavirus disease were reported in the United States since surveillance began in 1993. CDC states these were all laboratory-confirmed cases and included hantavirus pulmonary syndrome (HPS) and non-pulmonary hantavirus infection. 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 that non-pulmonary infections could be captured starting in 2015.
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 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.
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.
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.
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 9 May 2026. CDC updates surveillance pages after publication; confirm numbers and wording on the live site.