[MMR] Measles, Mumps, and Rubella

What It Is

The MMR vaccine protects against three viral illnesses:

• Measles – Spreads through the air, extremely contagious, can cause pneumonia, brain swelling, or death.

• Mumps – Causes swollen glands, fever, and can lead to meningitis or infertility.

• Rubella – Usually mild, but dangerous for pregnant women because it can cause severe birth defects.

  
  

  The vaccine is given in two doses (usually in childhood). For most people, this provides long-lasting protection.

Why Public Safety Needs It

• High Exposure Risk – First responders and healthcare workers often enter homes, hospitals, shelters, and other public spaces where undiagnosed, contagious individuals may be present.

• Protecting the Vulnerable – Infants, pregnant women, and immunocompromised people depend on you not to spread these diseases.

• Preventing Outbreaks in Teams – One infected responder can expose a whole shift, leading to sick time and service shortages.

• Professional Responsibility – Vaccination is part of the “protect and serve” mission — keeping yourself, your team, and your community safe.

How Immunity Can Change Over Time

• Not Everyone Responds to the First Shot – About 2–5% of people don’t get full protection until the second

  dose.

• Waning Immunity – Over decades, especially for mumps, protection can fade. This is why outbreaks sometimes occur even in vaccinated adults.

• Special Situations – People with weakened immune systems (due to illness or medication) may lose protection faster.

• Silent Past Infections – Some people test “immune” even without vaccination, because they had a mild or unnoticed infection earlier in life.

Why Testing Matters

Even though vaccination provides strong protection, the question of how long immunity lasts is especially important for first responders. That’s where antibody titer testing comes in. The section below explains why it has become a valuable part of occupational health exams — and why some debate around it continues.

Measles, mumps, and rubella (MMR) are viral illnesses that most people in the United States were vaccinated against in childhood. For many years, the assumption was that this protection would last a lifetime. While the vaccine is highly effective, new technology has shown us that immunity can wane in some individuals. That is why testing antibody titer which measures whether immunity remains— has become an important part of occupational health exams for first responders.

Some people question why providers for other friends and family members are recommending MMR titers. The reason is the added risk for public safety professionals are often the first point of contact for vulnerable populations, including children, the elderly, and people with weakened immune systems. If a first responder lacks immunity and is exposed, they risk becoming ill. And if they become ill, they risk spreading it to others. Verifying protection helps safeguard both the responder and the community.

Admittedly, there is debate. Some healthcare providers feel that repeat vaccination in adulthood is unnecessary if childhood vaccines were completed, while others follow CDC guidance, which supports confirming immunity in high-risk groups like healthcare workers and first responders. The science continues to evolve.

At Reserve Health, our approach is simple: we test titers to take the guesswork out of it. If immunity is present, no further action is needed. If immunity has waned, we can then discuss the safest and most appropriate next steps. Vaccines are never forced- it is a shared decision between you and your provider.

Bottom Line

The MMR vaccine remains one of the simplest ways to prevent highly contagious diseases from taking down first responders and the communities they serve. Whether through vaccination or titer testing, confirming immunity ensures you stay protected, your team stays strong, and your community stays safe.