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Within Hitchhikers

Is the hitchhiker effect really contagious?

Kelleher's contagion language may help structure cases, but it can also make an unproven pattern sound more biological than it is.

On this page

  • Why Kelleher borrows contagion ideas
  • How social network modelling could test reports
  • Where the infection metaphor can mislead
Preview for Is the hitchhiker effect really contagious?

Introduction

One of the more unusual aspects of Colm Kelleher’s hitchhiker-effect narrative is his use of contagion language. Rather than describing alleged post-Skinwalker experiences as isolated paranormal events, he has repeatedly suggested that they may spread through social or household networks in a way that resembles transmission. In public discussions and in his 2022 EdgeScience article, Kelleher explicitly linked the hitchhiker effect to “models of contagion”, arguing that experiences reported by investigators sometimes appeared to extend beyond the original witness and into families, workplaces or friendship circles. [The Black Vault]theblackvault.comThe Black Vault The Pentagon's Secret UFO Program, the Hitchhiker Effect,Colm A. Kelleher. Page 2. 20 / EDGESCIENCE #50 • JUNE 2022. Lacatski himself and his wife experienced a few, but not.Read more…Published: JUNE 2022

Contagion model illustration 1 The key point is that Kelleher is not claiming a proven infectious disease. Instead, he is borrowing concepts from epidemiology and network science as a way of organising reports that seem, in his view, to cluster around particular people after exposure to a location or event. Whether that analogy clarifies the phenomenon or exaggerates it is one of the central disputes surrounding the hitchhiker effect.

Why Kelleher borrows contagion ideas

Kelleher’s problem is partly a descriptive one. The hitchhiker claim does not fit neatly into conventional UFO categories because the reported effects are said to continue after a person leaves the original site. In his account, the important observation is not merely that someone sees an anomaly at Skinwalker Ranch, but that unusual experiences are later reported by spouses, children, colleagues or neighbours who never visited the location themselves. [The Black Vault]theblackvault.comThe Black Vault The Pentagon's Secret UFO Program, the Hitchhiker Effect,Colm A. Kelleher. Page 2. 20 / EDGESCIENCE #50 • JUNE 2022. Lacatski himself and his wife experienced a few, but not.Read more…Published: JUNE 2022

A contagion framework gives that pattern a structure.

Instead of treating each report as independent, the model asks questions familiar to epidemiologists:

  • Who was the first reported “exposure” case?
  • Which people had close contact with that individual?
  • Did experiences appear in connected households?
  • How long after the original encounter did reports emerge?
  • Did the pattern stop, continue or spread further?

This is why Kelleher’s writing often focuses on chains of association rather than single sightings. The reported sequence itself becomes the evidence being examined. If multiple people connected to one witness report similar events, he argues that the clustering deserves investigation rather than dismissal as coincidence. [The Black Vault]theblackvault.comThe Black Vault The Pentagon's Secret UFO Program, the Hitchhiker Effect,Colm A. Kelleher. Page 2. 20 / EDGESCIENCE #50 • JUNE 2022. Lacatski himself and his wife experienced a few, but not.Read more…Published: JUNE 2022

Supporters of the hitchhiker concept see this as a useful way to identify recurring features across otherwise confusing case reports. Critics argue that clustering alone does not establish a genuine transmission mechanism because beliefs, expectations, conversations and stress can also spread through networks.

How social-network modelling could test the claim

The strongest version of a contagion model would not rely on anecdotes. It would use formal social-network analysis.

Network science already studies how information, behaviours and beliefs move through groups. Researchers use techniques such as network-based diffusion analysis to determine whether a behaviour spreads through social connections in a statistically meaningful way or simply appears randomly distributed. [Wikipedia]WikipediaNetwork-based diffusion analysisNetwork-based diffusion analysis

Applied to hitchhiker claims, a rigorous study might attempt to map:

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  1. The original witness or exposure event.
  2. Family and social connections.
  3. The timing of reported experiences.
  4. The type of experiences reported.
  5. Independent corroboration where available.

Researchers could then compare observed patterns against chance expectations.

For example, if reports genuinely followed identifiable relationship networks more often than random distribution would predict, that would at least establish that a measurable social diffusion process exists. It would not prove a paranormal cause, but it would move the discussion beyond storytelling.

This distinction is important. A network analysis can demonstrate that something spreads through a group. It cannot automatically determine what that “something” is.

The spread might reflect:

  • Shared observation of an external event.
  • Shared interpretation of ambiguous experiences.
  • Suggestion and expectation effects.
  • Stress responses within a family.
  • Deliberate fabrication.
  • A presently unknown mechanism.

The method tests the pattern first and explains the cause second.

Contagion model illustration 2

The difference between biological contagion and social contagion

A major source of confusion is that “contagion” has more than one meaning.

In medicine, contagion implies transmission of a pathogen or biological agent. Evidence normally includes identifiable mechanisms, exposure pathways, biomarkers and reproducible effects.

In social science, contagion often refers to the spread of behaviours, emotions, beliefs or expectations through groups. Researchers have long studied social contagion in areas ranging from financial panics to online misinformation and public-health behaviour. [Wikipedia]WikipediaThree degrees of influenceThree degrees of influence

Kelleher’s public discussions sometimes move between these two meanings.

That creates ambiguity because some hitchhiker accounts involve reports of illness, autoimmune disorders or neurological symptoms, while others involve apparitions, dreams, perceived entities or household disturbances. These are very different categories of claim.

If a biological process is being proposed, the evidential burden becomes extremely high. Researchers would need medical records, comparison populations, exposure histories and reproducible clinical findings.

If a social process is being proposed, the investigation becomes more about communication, expectation, memory formation and group dynamics.

The public record has not yet established which interpretation, if either, best fits the reported cases.

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Where the infection metaphor can mislead

The infection metaphor is powerful because it provides an intuitive narrative.

People immediately understand the idea of exposure, transmission and spread. The language creates a sense of mechanism even when the mechanism remains unknown.

That is also where critics see a major problem.

Describing reports as “contagious” can make an unproven pattern sound more biologically grounded than it actually is. The terminology may unintentionally imply:

  • A disease-like process.
  • A measurable agent.
  • Predictable transmission.
  • Established causation.

None of those points has been demonstrated publicly in relation to the hitchhiker effect.

Sceptics therefore argue that the metaphor risks smuggling assumptions into the discussion. Once a case is framed as a contagion event, readers may start thinking in terms of infection before evidence of infection exists. Jason Colavito and other critics have argued that no public scientific demonstration has shown that experiences reported after Skinwalker-related investigations are causally linked to the ranch itself rather than to belief, expectation or coincidence. [X (formerly Twitter]x.comformerly Twitter)Skinwalker Ranch and the 'hitchhiker effectX (formerly Twitter)Skinwalker Ranch and the 'hitchhiker effect' - Jason ColavitoNo one making this claim has offered anything like scien…

The same criticism appears in broader debates around UAP belief systems. Some commentators suggest that social contagion may explain parts of the phenomenon more effectively than any physical transmission process, comparing waves of UFO belief to other episodes of collective interpretation and cultural diffusion. [House Document Repository]docs.house.govHHRG 118 GO12 Wstate ShellenbergerM 20241113House Document RepositoryThe United States Department Of Defense And The…13 Nov 2024 — Other UAP skeptics say that some combination of…

Contagion model illustration 3

The unresolved credibility question

The contagion model is one of the most revealing parts of Kelleher’s wider approach because it shows how he thinks about anomalous reports. Rather than treating experiences as isolated incidents, he looks for recurring patterns across connected individuals and households.

That instinct is not inherently unscientific. Epidemiology, network analysis and diffusion modelling are legitimate tools for studying clustered events. The difficulty is that the public evidence remains largely anecdotal. The reported networks, timelines and health outcomes have not been published in a form that allows independent researchers to test whether a genuine transmission pattern exists. [The Black Vault]theblackvault.comThe Black Vault The Pentagon's Secret UFO Program, the Hitchhiker Effect,Colm A. Kelleher. Page 2. 20 / EDGESCIENCE #50 • JUNE 2022. Lacatski himself and his wife experienced a few, but not.Read more…Published: JUNE 2022

As a result, the contagion framework currently functions more as a hypothesis-generating model than a verified explanation. It offers a way of organising witness reports, but it does not yet establish that the hitchhiker effect is literally contagious, biologically transmissible or even a single coherent phenomenon.

For readers assessing Kelleher’s credibility, that distinction matters. The underlying question is not whether clusters of unusual reports exist in his case narratives. It is whether the contagion metaphor identifies a real mechanism or merely provides an appealing structure for experiences that remain unexplained. The available public evidence does not yet resolve that question. [The Black Vault]theblackvault.comThe Black Vault The Pentagon's Secret UFO Program, the Hitchhiker Effect,Colm A. Kelleher. Page 2. 20 / EDGESCIENCE #50 • JUNE 2022. Lacatski himself and his wife experienced a few, but not.Read more…Published: JUNE 2022

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Endnotes

  1. Source: Wikipedia
    Title: Network-based diffusion analysis
    Link: https://en.wikipedia.org/wiki/Network-based_diffusion_analysis

  2. Source: Wikipedia
    Title: Three degrees of influence
    Link: https://en.wikipedia.org/wiki/Three_degrees_of_influence

  3. Source: docs.house.gov
    Title: HHRG 118 GO12 Wstate ShellenbergerM 20241113
    Link: https://docs.house.gov/meetings/GO/GO12/20241113/117721/HHRG-118-GO12-Wstate-ShellenbergerM-20241113.pdf
    Source snippet

    House Document RepositoryThe United States Department Of Defense And The...13 Nov 2024 — Other UAP skeptics say that some combination of...

  4. Source: theblackvault.com
    Title: The Black Vault The Pentagon’s Secret UFO Program, the Hitchhiker Effect,
    Link: https://www.theblackvault.com/casefiles/wp-content/uploads/2022/06/colmkelleher-edgescience.pdf
    Source snippet

    Colm A. Kelleher. Page 2. 20 / EDGESCIENCE #50 • JUNE 2022. Lacatski himself and his wife experienced a few, but not.Read more...

    Published: JUNE 2022

  5. Source: x.com
    Title: (formerly Twitter)Skinwalker Ranch and the ‘hitchhiker effect’
    Link: https://x.com/JasonColavito/status/1541157418838761476
    Source snippet

    X (formerly Twitter)Skinwalker Ranch and the 'hitchhiker effect' - Jason ColavitoNo one making this claim has offered anything like scien...

  6. Source: youtube.com
    Title: The Hitchhiker Effect
    Link: https://www.youtube.com/shorts/RACc_k9eJpQ
    Source snippet

    Joe Rogan & David PaulidesDavid Paulides joins Joe Rogan to expose the unsettling reality of the "Hitchhiker Effect." First made famous b...

  7. Source: open.spotify.com
    Link: https://open.spotify.com/episode/4Om0SpAE8DucMP9CdUADDB
    Source snippet

    Hitchhiker Effect - HOLOSKY PODCAST2 Mar 2026 — We break down the [Axelrod case]({{ 'axelrod-case/' | relative_url }}), the Witt family experiences, and the Kelleher household r...

Additional References

  1. Source: facebook.com
    Link: https://www.facebook.com/groups/2340648070/posts/10163134312978071/
    Source snippet

    Colm A. Kelleher Ph.D. Notes from his interviewsSuch as The Hitch Hiker Effect, Poltergeists and Contagions... Model, Social Contagion M...

  2. Source: facebook.com
    Link: https://www.facebook.com/groups/815616659631794/posts/1126363685223755/
    Source snippet

    Dangers of visiting Skinwalker RanchThe "Hitchhiker Effect " can be said to have had some grave links to this location as well as it seem...

  3. Source: cs.sfu.ca
    Link: https://www.cs.sfu.ca/~oschulte/teaching/socialnetwork/papers/SNA-intro-mohsen.pdf
    Source snippet

    School of Computing ScienceDifferent Aspects of Social Network Analysisby M Jamali · Cited by 369 — In this paper a state of the art surv...

  4. Source: facebook.com
    Link: https://www.facebook.com/officialdougiecorrado/posts/the-disturbing-truth-about-skinwalker-ranch/1240788571494095/
    Source snippet

    The DISTURBING Truth About SkinWalker RanchCriticism Skeptical author Robert Sheaffer believes the phenomenon at Skinwalker to be "almost...

  5. Source: facebook.com
    Link: https://www.facebook.com/61581735685073/posts/full-video-here-httpsyoutube7dqn5nebxow-five-pentagon-intelligence-officers-inve/122121796137057856/

  6. Source: facebook.com
    Link: https://www.facebook.com/newshour/posts/although-advances-in-ai-are-seen-by-president-trump-as-critical-to-the-nations-e/1425283482800227/
    Source snippet

    Bad enough before- now flooded with fake photos and unnecessary avatar enhancements to people, pets.Read more...

  7. Source: globalplayer.com
    Link: https://www.globalplayer.com/podcasts/42L335/
    Source snippet

    Theories of Everything with Curt Jaimungal - PodcastExploring theoretical physics, consciousness, Ai, and God in a technically rigorous m...

  8. Source: reddit.com
    Link: https://www.reddit.com/r/skinwalkerranch/comments/18hc2t7/hitchhiker_effect_share_your_thoughts_on_how_this/
    Source snippet

    Hitchhiker effect: Share your thoughts on how this can be...What are the ideas on how hitchhiker effect at skinwalker can be explained?...

  9. Source: etheses.whiterose.ac.uk
    Title: Ph D thesis andrew clark minor corrections
    Link: https://etheses.whiterose.ac.uk/id/eprint/34458/1/PhD_thesis_andrew_clark_minor_corrections.pdf
    Source snippet

    the Causal Foundations of Metamorphic Testingby AG Clark · 2023 · Cited by 3 — To this end, in this thesis, we draw on the fundamentally...

  10. Source: reddit.com
    Link: https://www.reddit.com/r/skinwalkerranch/comments/1trfh7c/hitchhiker_effect_and_models_of_contagio/
    Source snippet

    Hitchhiker Effect and Models of Contagio: r/skinwalkerranchParanormal 'contagion' based less on proximity, relation or interaction, but...

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