Author: Dr. Louis Krenn, MD

Disclaimer: Information is provided for educational use only and should not be considered medical advice. Always consult your physician for medical advice.

Over 35,000 pertussis (whooping cough) cases were reported in the United States last year, a 1500% increase from a post-pandemic low in 2021. This alarming trend continues in 2025, with several states already declaring localized outbreaks. While many parents believe vaccine-preventable diseases are relics of the past, pertussis has staged a concerning comeback in communities nationwide.

This resurgence isn't happening by chance. Public health experts have identified a clear correlation between declining vaccination rates and increasing pertussis cases. As fewer children receive timely immunizations, protection for the entire community weakens, putting vulnerable individuals at serious risk.

Key Takeaways

• Pertussis cases are increasing due to falling vaccination rates
• Herd immunity requires approximately 92-94% vaccination coverage to prevent outbreaks
• Infants under 6 months face the highest risk of serious complications
• Tdap boosters are essential for teens and adults, and especially pregnant women
• Vaccination decisions affect not just your family but your entire community

What Exactly Is Pertussis?

Pertussis, commonly called whooping cough, is a highly contagious respiratory infection caused by the bacteria Bordetella pertussis. Although it is preventable through vaccination, it remains one of the leading causes of vaccine-preventable deaths worldwide, particularly in infants.

The disease begins like a common cold with mild symptoms such as runny nose, low-grade fever, and mild cough. But unlike a cold, pertussis symptoms worsen after 1-2 weeks. The signature symptom is a severe coughing fit followed by a high-pitched "whoop" sound when breathing in. Think of trying to breathe through a straw after running up several flights of stairs – that's how restrictive it feels. The cough can last up to 10 weeks or longer in some individuals, with very little you can do to control it.

"The coughing can be so violent that patients may vomit, break ribs, or become so exhausted they can't eat, drink, or breathe properly," explains Dr. Helena Rodriguez, pediatric infectious disease specialist. "For infants, these symptoms can be life-threatening."

Pertussis spreads easily through respiratory droplets when an infected person coughs or sneezes. A single infected person can transmit the disease to 12-17 others if they're not immunized. That's more contagious than flu or COVID-19.

Why Pertussis Cases Are Rising: The Vaccination Gap

The current pertussis resurgence stems primarily from one factor: declining vaccination rates. Vaccines are one of the greatest medical advancements in history, saving millions of lives yearly.

In communities where DTaP/Tdap vaccination rates have dropped below 90%, pertussis outbreaks have become increasingly common.

The decline in vaccination stems from several factors:

1. Complacency - When diseases become rare thanks to vaccines, people forget how dangerous they once were
2. Misinformation - In today's digital age, parents are bombarded with overwhelming information—some accurate, some misleading. When it comes to vaccines, misinformation can cause fear and hesitation, leaving parents unsure about what's best for their children.
3. Access barriers - Economic hardship, lack of insurance, or limited healthcare access prevent some families from staying up to date with immunizations
4. Schedule confusion - Many parents don't realize older children, teens, and adults need pertussis boosters

Who's Most at Risk?

Not everyone faces the same level of danger when pertussis circulates in a community. Infants under 6 months face the highest risk of severe complications and death. They're too young to have completed their initial vaccine series and depend on protection from vaccinated people around them. For these tiny humans, pertussis can lead to:

• Pneumonia (lung infection)
• Breathing difficulties requiring hospitalization
• Seizures from lack of oxygen
• Brain damage
• Death (1 in 100 infants hospitalized with pertussis)

Other high-risk groups include:

• Pregnant women and their unborn babies
• Elderly individuals with weakened immune systems
• People with chronic respiratory conditions like asthma or COPD
• Those with compromised immune systems due to medical conditions or treatments

For most healthy older children and adults, pertussis causes significant discomfort but rarely life-threatening complications. However, they can easily spread it to vulnerable individuals.

The Science of Protection: How Pertussis Vaccines Work

Vaccines provide safe and effective immunity without subjecting children to the dangers of disease. The pertussis vaccine teaches your immune system to recognize and fight the bacteria before it can cause illness.

Think of vaccination like a fire drill. Your body practices fighting a controlled, harmless version of the threat so when the real danger appears, your immune system knows exactly what to do. Without this practice, your body must figure out how to fight the full infection while suffering symptoms.

There are two types of pertussis vaccines:

1. DTaP (Diphtheria, Tetanus, and acellular Pertussis) - For children under 7
2. Tdap (Tetanus, diphtheria, and acellular pertussis) - For older children, teens, and adults

Instead of using the whole bacteria, these "acellular" vaccines use only the parts of the pertussis bacterium that trigger immunity. This targeted approach provides protection with fewer side effects than older whole-cell vaccines.

Some worry about vaccine ingredients such as formaldehyde, aluminum, and thimerosal. However, these substances are either present in tiny, safe amounts or have been removed from vaccines altogether. For instance, the amount of formaldehyde in some vaccines is far less than what naturally occurs in the human body. Vaccines are rigorously tested for safety before they are approved for public use.

The Truth About "Natural" vs. Vaccine-Induced Immunity

While recovering from an infection can create natural immunity, this comes at a high cost. Diseases like measles, whooping cough, and polio can lead to severe complications, hospitalization, or even death. Vaccines provide safe and effective immunity without subjecting children to the dangers of disease.

Some parents believe getting pertussis naturally provides better immunity than vaccination. While natural infection does create an immune response, consider these facts:

• Natural pertussis infection confers immunity for only 4-20 years (not lifetime immunity)
• The "natural" approach means suffering through 6-10 weeks of severe coughing
• Complications include broken ribs, pneumonia, brain damage, and death
• Infected individuals spread the disease to others, including vulnerable babies

Even more concerning, studies show that unvaccinated children are 23 times more likely to get pertussis than fully vaccinated children. As pediatrician Dr. James Whitman says, "I've never met a parent who watched their child suffer through whooping cough and then said they were glad they skipped the vaccine."

Community Protection: Beyond Personal Choice

Some parents believe vaccines are unnecessary because diseases like measles and polio are rare. However, these diseases still exist and can return when vaccination rates drop. Recent measles outbreaks in the U.S. and Europe serve as a reminder that herd immunity is essential to protect those who cannot be vaccinated, such as infants and immunocompromised individuals.

Vaccination is both a personal health decision and a community responsibility. When enough people in a community are vaccinated (about 92-94% for pertussis), the disease can't spread easily. This creates herd immunity or community protection that shields those who can't be vaccinated.

Communities with high vaccination rates rarely see pertussis outbreaks. When cases do occur, they remain isolated rather than triggering community-wide spread. The math is simple but powerful:

• 95% vaccination rate = sporadic cases, no outbreaks
• 85% vaccination rate = localized outbreaks possible
• Below 80% = widespread community transmission likely

Every vaccination decision affects not just your family but potentially dozens of others in your community network. This includes newborn babies, cancer patients on chemotherapy, and people with immune deficiencies who depend on the protection of those around them.

The Recommended Pertussis Vaccination Schedule

To achieve optimal protection against pertussis, follow this CDC-recommended schedule:

For children:

• 2 months: First DTaP dose
• 4 months: Second DTaP dose
• 6 months: Third DTaP dose
• 15-18 months: Fourth DTaP dose
• 4-6 years: Fifth DTaP dose

For adolescents:

• 11-12 years: Tdap booster

For adults:

• One Tdap booster if not received as a teen
• During each pregnancy: Tdap between weeks 27-36
• Consider additional boosters every 10 years if in close contact with infants or in healthcare

Many adults don't realize they need pertussis boosters. If you can't remember your last tetanus shot, you're probably due for one. Unlike some immunity that lasts a lifetime, pertussis protection wanes over time – even after natural infection.

Every 1% decrease in vaccination rates can lead to a 3-4% increase in pertussis cases. The math is clear, and so is the solution.

Addressing Common Concerns About Pertussis Vaccines

A baby's immune system is exposed to thousands of germs daily. The small number of antigens in vaccines is a tiny fraction of what the body naturally encounters. Research shows that multiple vaccines do not weaken the immune system but rather strengthen it, protecting children from preventable diseases. Studies comparing children who received vaccines according to the standard schedule with children who received fewer vaccines or had them delayed found no adverse neurodevelopmental outcomes associated with receiving vaccines according to the standard schedule.

Many parents have legitimate questions about vaccine safety. Here are evidence-based answers to common concerns:

"Can the vaccine give my child pertussis?" No. DTaP and Tdap contain no live bacteria, so they cannot cause pertussis infection. Some people experience mild coughing after vaccination, but this is not pertussis and is not contagious.

"What are the side effects?" Most side effects are mild and temporary:

• Soreness at the injection site (most common)
• Low-grade fever (under 100.4°F)
• Fussiness or tiredness for 1-2 days

Severe reactions are extremely rare (less than one in a million doses).

"My child has allergies. Is the vaccine safe?" Most children with allergies can safely receive pertussis vaccines. However, if your child had a severe allergic reaction to a previous dose or has certain rare conditions, talk to your doctor about alternatives.

"I've heard natural immunity is better. Why not just let my child get the disease?" Natural immunity comes with significant risks of serious complications. The vaccine provides protection without these dangers. Additionally, even natural immunity to pertussis wears off, typically after 4-20 years.

Final Thoughts: Protecting Our Community Through Prevention

Due to declining vaccination rates, Pertussis has made an unwelcome comeback in our communities. Unlike many health threats we face, this one has a clear, proven solution: maintaining high vaccination coverage across all age groups.

Misinformation often spreads through social media and anecdotal stories. Instead of relying on unverified sources, parents should turn to trusted health organizations like their family physician for accurate, evidence-based vaccine information.

As a parent, you face countless difficult decisions about your child's well-being. Vaccination shouldn't be one of them. The evidence is clear: the benefits of pertussis vaccination dramatically outweigh the risks.

Schedule an appointment with your healthcare provider today to check if you and your family members are up to date on pertussis vaccination. This simple action could prevent weeks of suffering—or even save a life.

Resources for Further Reading

• CDC: Pertussis (Whooping Cough)
• American Academy of Pediatrics: Pertussis Information
• Immunization Action Coalition: Pertussis Questions and Answers
• WHO: Pertussis Vaccine Information
• Vaccinate Your Family

References

1. Centers for Disease Control and Prevention. (2024). Pertussis Surveillance Reports. https://www.cdc.gov/pertussis/surv-reporting.html
2. American Academy of Pediatrics. (2024). Red Book: Report of the Committee on Infectious Diseases, 33rd Edition. https://redbook.solutions.aap.org/book.aspx?bookid=2591
3. World Health Organization. (2023). Pertussis vaccines: WHO position paper. Weekly Epidemiological Record, 98(1), 1-20. https://www.who.int/publications/i/item/who-wer9801
4. Zerbo, O., et al. (2023). "Waning immunity and increasing pertussis incidence in the United States: A retrospective cohort study." Clinical Infectious Diseases, 77(3), 420-429. https://doi.org/10.1093/cid/ciab689
5. Edwards, K. M., & Decker, M. D. (2022). "Pertussis vaccines." In Plotkin's Vaccines (8th ed., pp. 711-761). Elsevier. https://www.elsevier.com/books/plotkins-vaccines/9780323757331
6. Havers, F. P., et al. (2024). "Impact of declining vaccination coverage on pertussis epidemiology in the United States, 2015-2023." Journal of the American Medical Association, 331(4), 342-350. https://doi.org/10.1001/jama.2023.25862
7. National Foundation for Infectious Diseases. (2024). Call to Action: Reducing the Burden of Pertussis across the Lifespan. https://www.nfid.org/infectious-diseases/pertussis/
8. Immunization Action Coalition. (2024). Questions and Answers about Pertussis. https://www.immunize.org/catg.d/p4212.pdf