HPV Strains 16 and 18 Cause 70% of HPV-Linked Cancers

Understanding HPV 16 and 18: The Strains Behind Most HPV Cancers

HPV is short for human papillomavirus, a common viral infection. While most HPV cases resolve safely on their own, strains 16 and 18 cause a majority of all HPV-related cancers.

HPV 16 and 18's Connection to Cancer

Of over 150 known HPV strains, HPV 16 and HPV 18 lead to roughly 70% of all cervical cancer cases as well as a significant proportion of vaginal, vulvar, penile, anal and oropharyngeal cancers.

HPV 16 alone accounts for over 50% of HPV malignant tumors. Meanwhile HPV 18 is responsible for just under 20%. Combined, infection with one or both raises cancer risk substantially compared to other strains.

Percentage Breakdown of Cancers Linked to HPV 16 and 18

The estimated percentage contributions of HPV 16 and 18 to different HPV-associated cancer cases are:

• Cervical cancer - Approximately 70%
  • HPV 16 - 60%
  • HPV 18 - 10%
• Vaginal cancer - Approximately 70%
  • HPV 16 - 54%
  • HPV 18 - 13%
• Vulvar cancer - Approximately 70%
  • HPV 16 - 48%
  • HPV 18 - 21%
• Penile cancer - Approximately 60%
  • HPV 16 - 35%
  • HPV 18 - 13%
• Anal cancer - 84-95%
  • HPV 16 - 72%
  • HPV 18 - 7%
• Oropharyngeal cancers - 70-80%
  • HPV 16 - 57%
  • HPV 18 - Not Available

As these breakdowns reflect, among cancer-causing HPV variants, HPV 16 dominates incidence rates, with HPV 18 trailing significantly behind in second place.

Comparing HPV 16 and 18

HPV 16 and 18 possess similarities as high-risk, cancer-linked strains under the umbrella of the same virus. However, some key differences between the two variants include:

• Prevalence - HPV 16 remains the most ubiquitous strain, while 18 ranks among the top five.
• Transmission - Both spread through intimate skin contact and bodily fluids.
• Clearance - HPV 16 less often clears from the body naturally than HPV 18.
• Cancers caused - HPV 16 links to more cancer types than 18.
• Cancer risk - HPV 16 carries double the cancer risk of HPV 18.

The Dunning-Kruger Effect

The Dunning-Kruger effect is a cognitive bias whereby people with limited knowledge or competence in a given area tend to overestimate their own expertise or capabilities. Essentially, some people are too ignorant to accurately appraise their own ignorance.

The effect was first described by social psychologists David Dunning and Justin Kruger in a 1999 paper after studying the metacognitive abilities of undergraduate students. The less skilled the students were, the more they overinflated their own perceived abilities.

Conversely, students with the highest skill levels tended to underestimate their competence relative to their peers. They assumed other students must know as much as them, when that wasn’t the case at all.

Key Characteristics of the Dunning-Kruger Effect

There are several key manifestations of the Dunning-Kruger effect consistently observed in research:

• Illusory superiority - People rate their skill level or competence as considerably above average when in reality it is below average.
• Inability to recognize gaps in knowledge/competence - Lack of awareness of how little they actually know or understand.
• Inability to recognize the skill/competence of experts - Failing to grasp another’s greater expertise due to one’s own deficit.
• Cognitive bias - A persistent skewing of perceptions consistent with internal assumptions and self-enhancement motives.

Together, these distortions lead people to make misguided conclusions tacitly encouraged by their limited comprehension and worldview.

Real-World Examples of the Dunning-Kruger Effect

Countless studies have replicated and affirmed the existence of this cognitive bias across many domains. But the effect also commonly plays out informally in people’s real-world decision making:

• Underprepared student overestimates readiness for an exam based on glancing at notes.
• Novice investor believes they grasp market factors better than seasoned traders.
• Beginner poker player thinks their casual experience makes them an expert on strategy.
• Mediocre employee believes they’re excelling and deserve top rank and pay.
• Inept manager fails to consult others with more expertise.

In even high-stakes contexts like medicine, finance, law and policy, the Dunning-Kruger effect distorts judgment and action in potentially harmful ways.

Overcoming the Dunning-Kruger Effect

While almost everyone falls victim to the Dunning-Kruger effect around some topics where they lack skills, strategies exist to counteract its misleading hold.

Engage in Intellectual Humility

Accepting the limits of your knowledge facilitates recognizing deficiencies and seeking improvement rather than overestimating present capabilities.

Compare Yourself to Others Critically

Rather than assuming you’re average or above, honestly compare your skills and performance to legitimately skilled people.

Receive External Feedback

Asking for frank evaluations from teachers, mentors and experts with appropriate credentials highlights areas needing work.

Consider Opposite Perspectives

Entertaining contradictory viewpoints calibrates internal beliefs and questions their certainty.

While completely eliminating such bias is impossible, active self-skepticism and objective data integration help counter the Dunning-Kruger effect’s misleading allure.

Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult with a healthcare professional before starting any new treatment regimen.