Rare Disease Day: Understanding Accessibility for People With Rare Conditions

Each year, Rare Disease Day highlights the experiences of people living with rare diseases and the gaps that can keep them from fully participating in everyday life, including online. One commonly cited estimate is that rare diseases affect more than 300 million people worldwide (see the EURORDIS and Rare Diseases International prevalence statement).

Rare diseases can look very different from person to person. Symptoms may be visible or invisible, stable or fluctuating, mild or severe. That variability matters for accessibility because many “standard” accommodations assume a consistent set of needs. Digital accessibility works best when it is flexible enough to support people whose access needs can change day to day.

Key takeaways

• Rare Disease Day is observed on February 28, or February 29 in leap years (the last day of February).
• In the United States, a rare disease is generally defined as one that affects fewer than 200,000 people, and there are more than 7,000 rare diseases.
• You do not need a separate design for every diagnosis. Focus on clear structure, multiple ways to complete tasks, and user control (time, motion, sensory input).
• Many teams use WCAG 2.2 (Web Content Accessibility Guidelines) as the technical baseline for accessible web content.
  
  

What counts as a rare disease

In the United States, a rare disease is commonly defined as a condition affecting fewer than 200,000 people (see the NCI definition of rare disease). Federal health agencies also note that more than 7,000 rare diseases affect tens of millions of people in the U.S. (see Rare Diseases at FDA).

Definitions can vary outside the U.S., so if you work internationally, confirm the relevant definition for your jurisdiction and sector.

Why accessibility planning should include rare conditions

Rare conditions can involve mobility, vision, hearing, speech, cognition, energy, pain, sensory processing, and more. Many people experience needs that are hard to “bucket” into a single category, such as:

• Cognitive fatigue (sometimes described as “brain fog”)
• Processing delays
• Chronic pain and fatigue
• Sensory sensitivity to motion, flashing, sound, or clutter
• Communication differences or intermittent speech

Designing only for the most common disability scenarios can leave gaps. Designing for variability helps more people succeed without forcing them to request special help.

Common digital accessibility barriers people with rare conditions report

People with rare diseases may encounter barriers such as:

• Interfaces that are difficult to navigate during cognitive fatigue or processing delays
• Experiences that rely heavily on visual cues, small targets, or complex layouts
• Time pressure, short session timeouts, or “hurry up” interactions
• Health portals or forms that do not work well with assistive technologies such as screen readers
• Motion, animation, or auto-updating content that can trigger nausea, headaches, distraction, or sensory overload

Even when these barriers are unintentional, the impact can be significant. Inaccessible design can make it harder to access healthcare, education, employment, and community participation.

Designing accessibility with rare conditions in mind

You do not need to build separate solutions for every diagnosis. Instead, build experiences that give people options.

Reduce cognitive load

A clear structure helps people who process information differently or need more time.

• Use plain language and predictable layouts (see W3C cognitive accessibility resources).
• Provide step-by-step guidance for complex tasks (see W3C pattern: clear step-by-step instructions).
• Keep forms calm and forgiving: clear labels, helpful examples, and error messages that explain how to fix the problem.

Reduce time pressure and support pacing

Time limits can exclude people who need breaks, move slowly, or lose focus.

• Avoid unnecessary time limits, or make them adjustable (see Understanding WCAG: Timing Adjustable).
• Warn users before a session time-out and, when possible, preserve their work (see Understanding WCAG: Timeouts).
• Save progress automatically so people can return later without having to start over.

Give users control over motion and distractions

Motion and auto-updates can be a health and access issue, not a preference.

• Let users pause, stop, or hide moving content (see Understanding WCAG: Pause, Stop, Hide).
• Provide a way to turn off non-essential motion triggered by interactions (see Understanding WCAG 2.2: Animation from Interactions).
• Respect “reduced motion” settings where possible and avoid auto-playing audio.

Support assistive technologies

Assistive technology compatibility is essential for many people managing rare conditions.

• Use proper headings, landmarks, and form labels so screen readers can interpret content accurately.
• Ensure focus indicators are visible and keyboard navigation works throughout.
• Make downloadable documents, especially health and benefits documents, accessible for repeated use.

The role of digital accessibility for rare disease communities

For many people living with rare diseases, digital access supports independence and connection. Telehealth, remote work, online education, and virtual communities can reduce barriers when in-person participation is limited. When websites, portals, and documents are accessible, people can spend less energy fighting the interface and more energy on what they came to do.

Compliance and policy notes (not legal advice)

Accessibility obligations depend on jurisdiction, sector, and context. In the U.S.:

• The Department of Justice provides Guidance on Web Accessibility and the ADA for both businesses open to the public and state and local governments.
• State and local governments have specific requirements under the ADA Title II web accessibility rule. The DOJ explains first steps and references WCAG 2.1 Level AA in State and Local Governments: First Steps Toward Compliance.
• U.S. federal agencies and many federal contractors follow Section 508, and the revised standards incorporate WCAG 2.0 Level AA (see Section508.gov applicability and conformance requirements).

If you are unsure what applies to your organization, consider getting guidance from qualified counsel or your procurement and compliance teams.