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Measles: The Epidemic of Ignorance

How a preventable virus returned to America and what South Carolina's outbreak reveals about the cost of misinformation

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Dr. Terry Simpson
Oct 14, 2025
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Did you see this headline:

153 children quarantined in South Carolina?


It’s not 1910. It’s 2025. And the virus behind it is not new: it is measles, a disease that we eliminated from the United States in 2000.

Now it's back in communities where misinformation spreads faster than the virus itself.

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📍 South Carolina: When Ignorance Becomes Outbreak

In Spartanburg County, 153 students are under 21-day quarantine after being exposed to measles.
Only six or seven confirmed cases so far — but measles can take up to three weeks to appear, and in that time it can infect dozens more.

This is three weeks of missed classes, closed classrooms, and anxious parents, all of which are preventable.

Why there? Spartanburg has the highest rate of religious vaccine exemptions in South Carolina, more than 8%.


That’s nearly one in twelve children unvaccinated.

Some say 90% coverage sounds great.
Not for measles.

This virus can linger in the air for two hours after an infected person leaves, and can infect someone a hundred feet away.
To stop it, we need at least 95% of people immune.

When you fall below that, measles doesn’t just return — it thrives.


📊 National Picture: The Numbers Behind the Outbreak

Across the U.S., vaccination coverage has quietly slipped:

  • Kindergarten MMR rates fell from 95.2% (2019-20) to 92.7% (2023-24).
    KFF Report

  • 39 states now sit below the 95% herd immunity line.

  • Among children under 24 months, only ~85% received measles vaccine by age 2 — down from pre-pandemic highs.
    Truveta Research

The MMR vaccine remains one of medicine’s greatest successes:

  • One dose: ~93% effective

  • Two doses: ~97% effective
    (CDC Data)

But even that 3% gap leaves thousands of kids vulnerable when their peers refuse vaccination.


To stop measles, we need ≥ 95% immunity.


🧬 The Science of Contagion

Measles has one of the highest reproduction numbers (R0) in all infectious diseases, usually between 12 and 18.
That means one case can infect a dozen or more unvaccinated people.

Compare that to:

  • COVID-19 (original strain): R₀ ≈ 2–3

  • Influenza: R₀ ≈ 1.3

  • Measles: R₀ ≈ 15

To break the chain, communities must keep immunity high enough that the virus runs out of hosts.
For this reason, 95% coverage is not optional, it is survival math.


🧩 Herd Immunity Thresholds

Source: CDC, Johns Hopkins, History of Vaccines


⚠️ Why This Matters

Each “religious exemption” chips away at community protection.
The children in quarantine are not punished, they are protected.
Because measles does not care about belief systems, it exploits ignorance.

We eliminated measles once.
It returned not because the virus evolved, but because we devolved.

If these parents had chosen a science education over an exemption form, their children and everyone else would be in school instead of isolation.

Faith can save souls.
Science saves lives.

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