Twitter Bots Comprised Nearly Half of COVID-19 Discussion Accounts

A Carnegie Mellon University study found that bots comprised up to 60 percent of Twitter accounts participating in COVID-19 discussions. These bots were used to amplify calls to reopen the country, undermining the integrity of public discourse.

Twitter · Incident May 21, 2020 · Indexed Jun 22, 2026 · 2 sources

Bots may account for between 45 and 60% of Twitter accounts discussing covid-19.
What
A Carnegie Mellon University study found that bots comprised up to 60 percent of Twitter accounts participating in COVID-19 discussions.
Incident date
May 21, 2020
Who
Twitter
Failure mode
Brand & Safety Incident
AI surface
Algorithmic Decision
Severity
High

What happened

Researchers from Carnegie Mellon University found that bots comprised between 45 and 60 percent of Twitter accounts discussing COVID-19. These bots were used to amplify specific messaging, particularly calls to reopen the United States. A majority of the most influential retweeters were likely bots.

What broke inside the model

Failure path · mode profile · Brand & Safety Incident
  1. 01 · TriggerA user prompts the model in public view.
  2. 02 · Model stepThe model produces unsafe or off-brand output.
  3. 03 · Control gapNo filter holds the line before publish.
  4. 04 · FailureThe output goes public unchecked.
  5. 05 · ConsequenceA reputational or safety incident lands.

A contained signal crosses into output that goes public.

Twitter's automated bot detection systems failed to identify and mitigate large-scale orchestrated bot campaigns. This allowed bot accounts to maintain high visibility and manipulate public discourse.

Public visibilityHigh
Regulatory exposurePossible
Customer impactClass-wide
Financial impactUnknown
Time to disclosureMonths
  1. PrimaryNearly Half of the Twitter Accounts Discussing 'Reopening America' May Be Botscmu.edu
  2. PressNearly half of Twitter accounts pushing to reopen America are botstechnologyreview.com
Permalinkhttps://failureindex.ai/failures/twitter-bots-comprised-nearly-half-covid
CitationAI Failure Index. "Twitter Bots Comprised Nearly Half of COVID-19 Discussion Accounts" (FI-0600). Realm Labs. https://failureindex.ai/failures/twitter-bots-comprised-nearly-half-covid (indexed Jun 22, 2026).
Share cardA branded image of this record for posts and slides.

Data fields CC-BY 4.0, prose citation permitted. Incident ID FI-0600. Full dataset at /data.

Note from Realm Labs, the Index steward

How Realm would have caught this

Controls for this failure mode
  • Prism
  • OmniGuard
  • AI Detection & Response (AIDR)

Realm watches the model's internal state for the signature of unsafe or off-brand generation and can block or reroute the output before it becomes public, in real time rather than after it has been screenshotted.