Our lives depend on the CDC because the agency is on the front line, protecting us from infectious diseases. Vaccinations are one of the most powerful tools in that fight, and the CDC ensures they are safe, effective and widely available. Without vaccines, diseases we’ve nearly defeated, like polio or measles, could return in full force.

The Centers for Disease Control and Prevention (CDC) plays a crucial role in public health, and our lives—especially when it comes to preventing dangerous diseases—depend on the work they do. Vaccinations are at the center of that mission. Here’s why:

1. The CDC tracks and controls outbreaks

• The CDC monitors diseases across the United States and around the world.
• When outbreaks occur—such as measles, polio or influenza—the CDC investigates quickly to contain them.
• Without that oversight, diseases could spread silently before anyone realized, putting millions at risk.

2. The CDC ensures that vaccines are safe

• Vaccines go through years of research and trials before approval, but the CDC continues monitoring them after they are in use.
• The agency tracks side effects through systems such as VAERS (Vaccine Adverse Event Reporting System).
• This helps identify rare problems quickly and ensures vaccines remain safe for the population.

3. The CDC provides science-based guidelines

• The CDC recommends vaccination schedules for children, adults, seniors and people with health conditions.
• These guidelines prevent confusion and make sure people get the right protection at the right age.
• For example, polio and smallpox vaccines helped nearly eliminate those diseases because of consistent CDC guidance.

4. The CDC educates the public

• Many people don’t realize how deadly diseases such as diphtheria, measles or polio once were.
• The CDC keeps history and data alive, reminding us what happens when vaccination rates drop.
• The agency’s campaigns increase public awareness and fight misinformation.

5. The CDC helps prevent pandemics

• The CDC’s global disease surveillance warns us about emerging threats.
• Vaccination programs for seasonal flu or new viruses reduce hospitalizations and deaths.
• Without the CDC coordinating national responses, pandemics like COVID-19 could have been even worse.

6. The CDC protects the most vulnerable

• Babies, seniors and people with weakened immune systems rely on herd immunity—the idea that if most people are vaccinated, diseases can’t spread easily.
• The CDC ensures vaccination rates stay high enough to shield those whose immune systems cannot shield them.

The vital role of vaccination and herd immunity: Why mandatory immunization protects us all

Human beings move through their daily lives with a certain sense of security. Parents send their children to school, people crowd into restaurants and theaters, athletes compete in stadiums filled with spectators, and travelers board planes that crisscross the globe. Few pause to wonder whether the person next to them carries diphtheria, measles, polio or smallpox. Few worry about iron lungs or mass graves filled with children lost to infectious disease. 

This freedom from constant fear is not accidental; it is one of the greatest achievements of modern medicine: the widespread use of vaccines.

Vaccination programs, coordinated and enforced by public health agencies, have transformed human life in just over a century. Diseases that once killed millions yearly are now controlled, eliminated, or even eradicated. The security that people take for granted today exists precisely because most citizens are immunized. But what would happen if vaccination were treated as a matter of personal preference rather than a public responsibility? What if parents were free to opt their children out of immunization requirements before school entry? The consequences would ripple through society: herd immunity would collapse, vulnerable populations would lose protection, and previously viruses would roar back, perhaps even in mutated, more dangerous forms. Our health depends on vaccination, how herd immunity functions, what history has taught us about disease resurgence, and why mandatory immunization is essential for safeguarding present and future generations.

School vaccination requirements

Recognizing this responsibility, public health authorities established vaccination requirements for children entering school. These laws, which exist in every U.S. state and many countries worldwide, ensure that children are immunized against measles, mumps, rubella, polio, diphtheria, pertussis, and other diseases before they join crowded classrooms.

The logic is clear: schools are breeding grounds for contagion. Children interact closely, share supplies and spend long hours indoors. Without vaccination requirements, these institutions could become epicenters of outbreaks. History proves the wisdom of these laws. Where compliance is high, outbreaks vanish. Where exemptions proliferate, disease reemerges.

Consider measles. Declared eliminated in the United States in 2000, measles returned in 2025, fueled by communities with low vaccination rates. Hundreds of children became sick, some requiring hospitalization and some died. These outbreaks were not acts of nature. These resulted from policies permitting parents to opt out of immunizing their children.

What if vaccination were only a choice?

Imagine a world where parents were free to decide whether to vaccinate their children without consequence. Some might still choose vaccination, but many would not—whether from misinformation, fear of side effects, religious beliefs or simple neglect.

The first consequence would be a decline in herd immunity. Viruses thrive in gaps. If measles vaccination rates dropped below 95 percent, outbreaks would spread like wildfire. If polio immunization rates fall below the 85 percent herd immunity threshold, poliovirus could return to America from regions where it still exists.  A disease once nearly eradicated could again cripple children and adults within weeks.  The three polioviruses could mutate (change), leaving those already immunized for polio vulnerable once again.  The percentage of paralysis rates could be sky high. 

The second consequence would be greater vulnerability of those who cannot choose. Infants too young for vaccines would be left exposed in a world where contagion lurks. Cancer patients undergoing chemotherapy, organ transplant recipients, and people with immune disorders would live in constant danger. The very people society has a moral obligation to protect would be sacrificed to misplaced notions of “personal freedom.”

Learn from history

The dangers of optional vaccination are not hypothetical. They have played out repeatedly in history.

• Measles in Europe: In the 2010s, declining vaccination rates in parts of Europe led to tens of thousands of measles cases, with dozens of deaths. The outbreaks spread rapidly among unvaccinated communities, then spilled into the broader population.
• Pertussis in the US: The resurgence of whooping cough in states with high exemption rates demonstrates the direct link between lax vaccination policies and disease return. Infants, too young for full immunization, suffered the worst outcomes.
• Polio in Nigeria: In the early 2000s, rumors about the safety of the polio vaccine led to boycotts in northern Nigeria. The virus surged, paralyzing thousands of children and spreading to other countries that had been polio-free for years.

These examples underscore a sobering truth: when immunization falters, disease roars back.

Vaccination, trust and public responsibility

Opponents of mandatory vaccination often frame the issue as one of personal liberty. Shouldn’t parents have the right to decide what goes into their children’s bodies? While individual rights are important, public health requires balancing personal freedom with collective safety. Society accepts countless restrictions for the common good—traffic laws, food safety regulations, seat belt requirements. Vaccination mandates fall squarely within this tradition.

Trust in scientific institutions like the Centers for Disease Control and Prevention is essential. These organizations monitor vaccine safety, track adverse reactions, and adjust recommendations based on evidence. While no medical intervention is risk-free, the dangers of disease vastly outweigh the rare side effects of vaccines. The measles vaccine, for example, prevents millions of deaths worldwide each year. The risk of a serious adverse event is less than one in a million. By contrast, measles kills one in every thousand infected children.

Public health is not sustained by fear but by trust: trust that vaccines are safe, trust that neighbors will also vaccinate, and trust that government agencies act in the best interest of the population. When that trust is eroded by misinformation or political polarization, the consequences extend far beyond individual families. They endanger the fabric of community life.

The potential devastation of widespread outbreaks

Beyond the human toll, the economic and social costs would be staggering. Outbreaks strain healthcare systems, disrupt education, and slow economies. The COVID-19 pandemic offered a painful reminder of how infectious diseases can bring modern life to a halt. Now imagine that scenario repeating, not with a novel virus, but with old foes we had already defeated.

Why mandatory immunization must endure

The logic is inescapable. Vaccination works, but only when widely adopted. Herd immunity protects the vulnerable, but only when thresholds are met. Optional vaccination guarantees decline in coverage, resurgence of disease, and avoidable suffering.

Mandatory immunization before school entry is not an infringement of liberty; it is the safeguard of liberty. It is what allows children to gather in classrooms without fear, parents to pursue careers without constant dread, and society to function without epidemics tearing through its core. The freedom people cherish—the freedom to live without fear of iron lungs, quarantine wards, and mass graves—exists precisely because previous generations accepted the responsibility of vaccination.

Life today is lived in the shadow of countless unseen protections. People shop, travel, and embrace without the constant terror that once haunted every parent in the polio years or every household during smallpox epidemics. That security is fragile, built on the collective shield of vaccination. To treat immunization as an individual choice rather than a collective duty is to gamble with the health of millions.

Herd immunity is not just a scientific concept; it is a moral covenant. It says: “I will protect your child, and you will protect mine.” When that covenant is broken, society unravels. Diseases long banished return. Viruses  pay the price.

Herd immunity declines; Virus A mutates, sparking a new epidemic.   We now have the technology to make a vaccine in 9 months.  How many will die in those 9 months?  Will this administration pay for the research and distribution of the vaccine?   You had better begin asking these questions and start writing letters.  

The lesson of history is clear: mandatory vaccination saves lives. Without it, we risk returning to a past of fear and devastation. With it, we secure a future where children grow up free from the diseases that once ravaged humanity. That is why our lives, and the lives of generations to come, depend on vaccination and the policies that ensure its universal adoption.

The Centers for Disease Control and Prevention MUST be directed by a physician who believes in scientific methodology and strong and safe immunization programs, not someone with little or no understanding of what it’s all about.  Certainly not an anti-vaxxer.

Michael Kossove is professor emeritus and an adjunct professor of microbiology at Touro University's School of Health Sciences.