Virus Risk Perspective: Comparing 15 Viruses Side by Side

• Annual exposure / cases (US): 10400000-16700000
• Severe outcome rate: Data not available
• Hospitalization rate: Data not available
• Case fatality rate: Data not available
• Annual deaths (US): 34000-53000

Source: CDC MMWR — Respiratory Virus Activity, United States, July 1, 2024–June 30, 2025 · Data as of 2026-02-19 · WHO region: AMRO · Surveillance confidence: moderate

Illness/hospitalization/death figures are Oct 1, 2024–Jul 5, 2025 modeled range estimates; COVID-19 is no longer nationally notifiable, so no clean confirmed-case count exists. cases_per_100k and case_fatality_rate_pct were considered for derivation in Phase B (SITE-PLAYBOOK.md §12a) but deliberately left UNAVAILABLE: both the case and death figures are ranges, not point estimates, and there's no stated pairing between a specific low/high case bound and its corresponding low/high death bound — deriving a rate would require inventing a pairing method CDC doesn't specify.

• Annual exposure / cases (US): 1000+
• Severe outcome rate: Data not available
• Hospitalization rate: Data not available
• Case fatality rate: 25-50%
• Annual deaths (US): Data not available

Source: CDC — Ebola Outbreak: Current Situation · Data as of 2026-06-22 · WHO region: AFR · Surveillance confidence: moderate

case_fatality_rate_pct is the CDC-stated historical range for Bundibugyo species specifically (2 prior outbreaks: 25% and 50%), not a finalized rate for the current 2026 outbreak, which CDC has not yet published as a single figure.

• Annual exposure / cases (US): Data not available
• Severe outcome rate: Data not available
• Hospitalization rate: Data not available
• Case fatality rate: 38%
• Annual deaths (US): Data not available

Source: CDC — Reported Cases of Hantavirus Disease · Data as of 2026-05-08 · WHO region: AMRO · Surveillance confidence: high

CDC's own page reports only a cumulative total (890 cases, 1993-2023), not a clean single-year annual figure, so annual_exposure_or_cases_estimate is UNAVAILABLE rather than substituting the cumulative number. case_fatality_rate_pct (38%) is specifically for hantavirus pulmonary syndrome once respiratory symptoms develop. severe_outcome_rate_pct/hospitalization_rate_pct left UNAVAILABLE after a Phase B literature search: HPS by clinical case definition already involves respiratory failure, so a distinct 'hospitalization rate' may not be a meaningful CDC/literature statistic; the only figure found (67% required mechanical ventilation) came from a 12-patient pediatric case series, too narrow to represent the general population.

• Annual exposure / cases (US): 19000000-21000000
• Severe outcome rate: Data not available
• Hospitalization rate: Data not available
• Case fatality rate: Data not available
• Annual deaths (US): 570-800

Source: CDC (Emerging Infectious Diseases) — Norovirus Disease in the United States · Data as of 2013-08-08 · WHO region: AMRO · Surveillance confidence: moderate

This is CDC's own synthesized multi-study burden estimate; it is the most recent CDC-published figure verifiable with a static, citable number, though the underlying publication date is 2013. Norovirus is not individually case-reportable, so no more recent CDC aggregate figure with a direct URL was found.

• Annual exposure / cases (US): 2288
• Severe outcome rate: Data not available
• Hospitalization rate: 11%
• Case fatality rate: 0.13%
• Annual deaths (US): 3

Source: CDC — Measles Cases and Outbreaks · Data as of 2026-06-25 · WHO region: AMRO · Surveillance confidence: high

annual_exposure_or_cases_estimate and annual_deaths_estimate are full-year 2025 confirmed totals. hospitalization_rate_pct (11%) is from the CDC MMWR Jan-Apr 2025 update, the most specific percentage CDC published. case_fatality_rate_pct is a same-record derivation (deaths ÷ cases, both CDC full-year 2025 US totals) per the tiered-sourcing/derivation policy (SITE-PLAYBOOK.md §12a) — previously left UNAVAILABLE when derivation from raw CDC figures wasn't yet permitted.

• Annual exposure / cases (US): Data not available
• Severe outcome rate: Data not available
• Hospitalization rate: Data not available
• Case fatality rate: Data not available
• Annual deaths (US): Data not available

Source: CDC — Monkeypox in the United States and Around the World: Current Situation · Data as of 2026-06-01 · WHO region: AMRO · Surveillance confidence: moderate

CDC's own case-data page is dashboard-rendered without a static aggregate total in page text, so all funnel fields are UNAVAILABLE rather than substituting figures from secondary press coverage. A Phase B literature search for a Tier 1.5/2 severe-outcome or hospitalization rate found only fragmented, subgroup-specific figures (e.g. a vaccinated-subgroup hospitalization count in one CDC surveillance update) — none representative enough of the general US case population to populate a funnel field responsibly.

• Annual exposure / cases (US): Data not available
• Severe outcome rate: Data not available
• Hospitalization rate: 91.7%
• Case fatality rate: 11%
• Annual deaths (US): Data not available

Source: CDC — Historic Data (2004-2025), Powassan Virus · Data as of 2026-06-02 · WHO region: AMRO · Surveillance confidence: high

case_fatality_rate_pct (11%) is from a CDC-authored 2006-2016 cohort study (11 of 99 cases died), not a current-year figure — the most rigorous CDC-sourced CFR verifiable. hospitalization_rate_pct (91.7%) is a separate, Tier 2 figure (264 of 288 CDC-reported cases, 2004-2022, per a 2023 systematic review) — a different underlying case set/period than the CFR cohort above; not additive or directly comparable to it. severe_outcome_rate_pct left UNAVAILABLE: Powassan neuroinvasive disease is the only form nationally notifiable, so any 'severe outcome' percentage drawn from this surveillance stream would reflect ascertainment bias (mild/non-neuroinvasive infections are essentially never captured) rather than a true population rate.

• Annual exposure / cases (US): 3600000-6500000
• Severe outcome rate: Data not available
• Hospitalization rate: Data not available
• Case fatality rate: Data not available
• Annual deaths (US): 10000-23000

Source: CDC MMWR — Respiratory Virus Activity, United States, July 1, 2024–June 30, 2025 · Data as of 2026-02-19 · WHO region: AMRO · Surveillance confidence: high

annual_exposure_or_cases_estimate is outpatient visits (Oct 1, 2024-May 3, 2025), the closest CDC equivalent to a case estimate since RSV isn't individually notifiable; hospitalizations were 190,000-350,000 in the same window. hospitalization_rate_pct was considered for derivation in Phase B (SITE-PLAYBOOK.md §12a) but deliberately left UNAVAILABLE: both the hospitalization count and the outpatient-visit denominator are ranges with no stated low/high pairing, so a derived rate would require inventing a pairing method CDC doesn't specify.

• Annual exposure / cases (US): 51000000
• Severe outcome rate: Data not available
• Hospitalization rate: Data not available
• Case fatality rate: 0.09%
• Annual deaths (US): 45000

Source: CDC — 2024-2025 Influenza Season Summary: Severity, Disease Burden, and Burden Prevented · Data as of 2026-03-12 · WHO region: AMRO · Surveillance confidence: high

2024-25 was classified 'high severity' — the most severe season since 2017-18. CDC's own long-run range (2010-2025) is 9.4M-51M illnesses and 6,300-52,000 deaths, so this single season sits at the top of that range. case_fatality_rate_pct is a same-record derivation (deaths ÷ illnesses, both CDC 2024-25-season modeled estimates) per SITE-PLAYBOOK.md §12a; both inputs are model-based CDC burden estimates, not raw notified counts, since seasonal influenza isn't individually reportable.

• Annual exposure / cases (US): Data not available
• Severe outcome rate: Data not available
• Hospitalization rate: Data not available
• Case fatality rate: Data not available
• Annual deaths (US): Data not available

Source: CDC — Zika Cases in the United States · Data as of 2026-06-16 · WHO region: AMRO · Surveillance confidence: high

CDC states no local mosquito-borne Zika transmission has been reported in the continental US since 2018, and no confirmed cases from US territories since 2019. The case-count table on this page could not be extracted as a clean static annual figure with certainty, so funnel fields are UNAVAILABLE rather than guessed.

• Annual exposure / cases (US): 2770
• Severe outcome rate: Data not available
• Hospitalization rate: Data not available
• Case fatality rate: Data not available
• Annual deaths (US): 208

Source: CDC MMWR — West Nile Virus and Other Nationally Notifiable Arboviral Diseases, United States, 2023 · Data as of 2025-06-12 · WHO region: AMRO · Surveillance confidence: high

annual_exposure_or_cases_estimate and annual_deaths_estimate cover all six nationally notifiable arboviral diseases combined (West Nile is 95% of cases), since CDC reports these jointly in this MMWR. cases_per_100k and case_fatality_rate_pct were considered for derivation in Phase B (SITE-PLAYBOOK.md §12a) but deliberately left UNAVAILABLE: both inputs cover the combined 6-disease total, not West Nile virus alone, so a derived figure would misrepresent this specific pathogen's rate rather than merely reflect an imprecise period.

• Annual exposure / cases (US): 3798
• Severe outcome rate: Data not available
• Hospitalization rate: 36.1%
• Case fatality rate: 0.2%
• Annual deaths (US): 6

Source: CDC MMWR — Increase in Travel-Associated and Locally Acquired Dengue Cases, United States, 2024 · Data as of 2026-05-15 · WHO region: AMRO · Surveillance confidence: high

97.2% of 2024 cases were travel-associated; 2.8% locally acquired (Florida, California, Texas). cases_per_100k is a Tier 1.5 derivation (CDC 2024 case count ÷ US Census Vintage 2024 population estimate) per SITE-PLAYBOOK.md §12a — previously left UNAVAILABLE when derivation from raw CDC figures wasn't yet permitted. severe_outcome_rate_pct left UNAVAILABLE: CDC's MMWR on 2010-2021 US travel-associated dengue reports severe dengue as a small proportion of cases ("<1%") but does not publish an exact percentage — forcing that qualitative language into a point estimate would overstate precision CDC itself doesn't claim.

• Annual exposure / cases (US): 1400000
• Severe outcome rate: Data not available
• Hospitalization rate: Data not available
• Case fatality rate: Data not available
• Annual deaths (US): Data not available

Source: CDC — Rabies in the United States: Protecting Public Health · Data as of 2026-02-10 · WHO region: AMRO · Surveillance confidence: high

annual_exposure_or_cases_estimate (1.4 million) is Americans who seek healthcare for a possible rabies exposure annually; of these, 100,000 receive post-exposure prophylaxis. CDC states deaths are 'fewer than 10' per year rather than a precise figure, and states the disease is 'nearly 100%' fatal without timely PEP once symptoms begin — both left as qualitative CDC language rather than forced into a point-estimate percentage.

• Annual exposure / cases (US): 70
• Severe outcome rate: Data not available
• Hospitalization rate: Data not available
• Case fatality rate: 1.43%
• Annual deaths (US): 1

Source: CDC — A(H5N1) Bird Flu Response Update, March 19, 2025 · Data as of 2025-03-19 · WHO region: AMRO · Surveillance confidence: high

70 is a cumulative outbreak total (since April 2024) rather than a clean annual figure; 41 cases were dairy-cow exposure, 26 poultry exposure. No human-to-human transmission identified. cases_per_100k and case_fatality_rate_pct are derivations per SITE-PLAYBOOK.md §12a — both explicitly labeled as covering the outbreak-to-date window (not a calendar year) and, for CFR, the mild US outbreak specifically (not the far higher global historical H5N1 rate).

• Annual exposure / cases (US): 14
• Severe outcome rate: Data not available
• Hospitalization rate: Data not available
• Case fatality rate: 24-88%
• Annual deaths (US): 9

Source: CDC — Marburg Outbreak in Ethiopia: Current Situation · Data as of 2026-01-29 · WHO region: AFR · Surveillance confidence: moderate

annual_exposure_or_cases_estimate (14) and annual_deaths_estimate (9) are the final totals for Ethiopia's first-ever Marburg outbreak (Nov 2025-Jan 2026), which CDC/Ethiopia declared over on Jan 26, 2026. case_fatality_rate_pct is WHO's stated historical range across all outbreaks ('around 50% on average, 24-88% range'), not specific to this outbreak. No Marburg cases have ever been reported in the US; CDC assessed risk to the US public as low throughout this outbreak.