vital-scans open quality ledger

www.cdc.gov: week 2026-W28

This is the 2026-W28 ISO-week report (1967 pages fetched, 1783 unique pages audited by axe/Alfa). Generated 2026-07-24. Compared against 2026-W27 (1667 fetched). The dashboard headline uses a rolling last-7-days window; this page is the full ISO week. Machine-readable API: snapshot.json · findings.json.

Primary standards queue: 0 required finding type(s) (handling: report). Verification queue: 39 required finding type(s) (handling: review). Aspirational queue: 0 finding type(s). Advisory queue: 0 finding type(s). Unmapped review queue: 18 finding type(s).

New this week
0
Fixed this week
0
Regressed this week
3

Fix these first

Highest-leverage issues, ranked by pages affected × severity × people reached. Fixing a shared component often clears many pages at once. Issue links go to the full bug detail on the Accessibility page.

Top 8 issues to prioritize this week.
IssueSeverityPagesWho it affectsHow to fixEvidence
All page content should be contained by landmarks (WCAG criterion undetermined) (rule↗) Serious 1783 — Wrap all page content in landmarks (header, nav, main, footer) so users can navigate by region. pages (CSV)
Target size is at least 44×44 CSS pixels (Enhanced) (WCAG 2.5.5) (rule↗) Moderate 902 — See remediation guidance: https://alfa.siteimprove.com/rules/sia-r111 pages (CSV)
Images must have alternative text (WCAG 1.1.1) (rule↗) Critical 400 Without vision, Limited vision Give every <img> a meaningful alt attribute. Use alt="" only for decorative images so screen readers skip them. pages (CSV)
Text has enhanced contrast (WCAG 1.4.6) (rule↗) Moderate 738 — Increase text contrast to meet WCAG AAA (7:1). pages (CSV)
Scrolling content can be accessed by keyboard (WCAG criterion undetermined) (rule↗) Moderate 651 — See remediation guidance: https://alfa.siteimprove.com/rules/sia-r57 pages (CSV)
Elements must meet minimum color contrast ratio thresholds (WCAG 1.4.3) (rule↗) Serious 430 Limited vision, Without color perception Increase the contrast between text and its background to at least 4.5:1 (3:1 for large text). Check both light and dark modes. pages (CSV)
Heading levels should only increase by one (WCAG criterion undetermined) (rule↗) Moderate 614 — Use heading levels in order (h1 → h2 → h3) without skipping; structure, not size. pages (CSV)
<html> element must have a lang attribute (WCAG 3.1.1) (rule↗) Serious 367 Without vision, Limited cognitive, language, or learning ability Add a lang attribute to <html> (e.g. lang="en"). pages (CSV)

Progress

Open findings by severity over 5 weeks (lower is better)
Critical Serious Moderate Minor W24W26W28500

Dropped from this week's sample

These stopped appearing in scan results, but their pages were not re-checked this week — this is not a confirmed fix.

This week at a glance 75 issue type(s)
Median axe violations / page
5
Pages with axe violations
1783 of 1783
Median Alfa failures / page
80
Pages with Alfa failures
902 of 902
Unique pages audited
1783
Lighthouse performance (median)
82/100 173 sampled details
Lighthouse SEO (median)
100/100
Lighthouse best practices (median)
96/100
Lighthouse agentic (median)
100/100
Words per page (median)
759 main content, nav excluded
Reading ease (median)
44.2 803 prose pages
Reading grade (median)
12.5
Misspellings
25+ distinct details
Broken links
419 details
Median page weight
5.1 MB -111 KB better
Median requests per page
45
Estimated energy per page (mean)
1.4602 Wh

Note: page counts differ between weeks (1667 → 1967). Prefer the "pages affected" columns over raw instance counts when comparing.

Scan coverage this week (1967 pages · 1920 succeeded of 2107 attempted)
Pages each engine ran on, per the configured weekly sampling rates.
EnginePagesCoverage
axe178391%
resources178391%
standards91446%
plain-language91246%
alfa90246%
sustainability22411%
tech19410%
security1769%
lighthouse1759%
deprecated-html1608%

History & Trends → Severity, Lighthouse and other measures across 17 weeks.

Changes since 2026-W27 15 change(s)

axe-core

  • New: aria-input-field-name appeared this week.
  • New: valid-lang appeared this week.
  • Resolved: landmark-banner-is-top-level no longer fails on any scanned page.
  • Resolved: landmark-no-duplicate-banner no longer fails on any scanned page.
  • Resolved: document-title no longer fails on any scanned page.
  • aria-allowed-role spread: 29 → 86 pages affected (rate: 2% → 5% of pages scanned).

Alfa

  • Resolved: sia-r1 no longer fails on any scanned page.
  • sia-r2 spread: 190 → 201 pages affected (rate: 24% → 22% of pages scanned).
  • sia-r4 spread: 177 → 185 pages affected (rate: 23% → 21% of pages scanned).
  • sia-r73 spread: 297 → 310 pages affected (rate: 38% → 34% of pages scanned).
  • sia-r11 shrank: 64 → 54 pages affected (rate: 8% → 6% of pages scanned).
  • sia-r69 spread: 248 → 263 pages affected (rate: 32% → 29% of pages scanned).
  • sia-r68 spread: 80 → 114 pages affected (rate: 10% → 13% of pages scanned).
  • sia-r78 shrank: 68 → 53 pages affected (rate: 9% → 6% of pages scanned).
  • sia-r8 spread: 31 → 55 pages affected (rate: 4% → 6% of pages scanned).

Embedded & linked resources

Non-HTML resources this site links to or embeds — PDFs, Office documents, iframes, and media. The site owner is responsible for their accessibility too. Full inventory with first-seen dates: CSV.

New this week (3335)

3949 distinct resources, by type.
TypeCount
PDF documents3372
Images309
Embedded media players66
Spreadsheets51
Video files50
Iframes42
Word/text documents22
Archives (zip, etc.)19
Audio files14
Presentations4