Whooping Cough (Pertussis): Symptoms, Causes, Treatment & Prevention

Overview

Whooping Cough (Pertussis), also called pertussis, is a highly contagious bacterial infection that affects the respiratory tract. It’s caused by Bordetella pertussis and is best known for its long coughing fits, often followed by a sharp intake of breath that creates the classic “whoop” sound. Before vaccines were introduced, pertussis was considered a common childhood illness, but today it can affect people of all ages — especially infants who are too young to be vaccinated, older children, teenagers, and adults whose immunity has faded.

Although many people recover without complications, pertussis can be life-threatening in babies under one year of age. Vaccination remains the best defense, protecting individuals and communities from outbreaks.

Symptoms and Stages

Whooping Cough (Pertussis) typically develops in three stages, and symptoms can last for weeks or even months, which is why it’s sometimes called the “100-day cough.”

• Stage 1 (Cold-like phase): Symptoms begin about 5 to 10 days after exposure, sometimes as late as 3 weeks. Early signs resemble a common cold — mild cough, runny nose, watery eyes, sneezing, sore throat, fatigue, and a low-grade fever. Infants may show pauses in breathing (apnea) instead of coughing.
• Stage 2 (Severe cough): After one to two weeks, the illness worsens. Thick mucus builds in the airways, causing violent, uncontrollable coughing fits (paroxysms). These can last for a minute or more, often followed by vomiting, exhaustion, or the signature “whoop” sound as the person gasps for air. Coughing fits may happen day and night, often worse at night, and can be triggered by eating, laughing, or crying. Babies may turn red or blue in the face during episodes.
• Stage 3 (Recovery): The coughing slowly improves over several weeks, though milder coughing may linger. During this phase, people are still vulnerable to other respiratory infections, and catching a new illness can trigger the cough to flare again.

In adults and teens, symptoms may be milder, sometimes presenting as just a persistent, nagging cough without the whooping sound.

Causes and Transmission

Pertussis is caused by the bacterium Bordetella pertussis. It spreads when an infected person coughs, sneezes, or laughs, releasing tiny droplets into the air. These can be inhaled by others or land on surfaces where they’re later touched. The bacteria attach to the lining of the respiratory tract, producing toxins that damage tissues, cause swelling, and trigger the violent coughing reflex.

People with pertussis are contagious from the start of cold-like symptoms until at least three weeks after coughing fits begin — or until they’ve taken antibiotics for five days. Infants, who cannot be vaccinated until two months of age, are particularly vulnerable when exposed.

Risk Factors

Anyone can get pertussis, but certain groups face greater risks:

• Infants under 12 months, especially under 6 months, are at the highest risk of severe complications and death.
• Unvaccinated children and those who haven’t received all their doses of DTaP.
• Teens and adults whose childhood immunity has faded.
• Pregnant women who haven’t received a Tdap booster, as they can pass the infection to their newborn.
• People with weakened immune systems, chronic lung disease, or other health conditions.

Complications

The severity of complications depends on age.

In infants and young children, pertussis can cause pneumonia, ear infections, seizures, dehydration, apnea, brain damage, and even death. Babies may require hospitalization, sometimes in intensive care.

In teens and adults, complications are usually related to the strain of violent coughing, such as broken ribs, abdominal hernias, fainting, burst blood vessels in the eyes, urinary incontinence, and exhaustion. Pneumonia is also a risk in older patients.

Diagnosis

Because early pertussis looks like a common cold or bronchitis, diagnosis can be tricky. Doctors may recognize the disease by the distinct sound of the cough, but laboratory tests confirm infection.

• Nasal or throat swab: A sample is tested for the presence of Bordetella pertussis.
• Blood tests: Used to check for infection and immune response.
• Chest X-ray: Sometimes ordered to check for pneumonia or lung inflammation.

Treatment

Whooping Cough (Pertussis) is treated with antibiotics, such as azithromycin or erythromycin, which help prevent spreading the infection to others. They may also reduce severity if started early, but once the coughing fits are established, antibiotics usually don’t stop them.

Infants and people with severe symptoms may need hospital care, where they can be monitored for breathing problems, given oxygen, or treated for complications.

At home, supportive care is crucial: rest, hydration, small frequent meals (to avoid vomiting), clean air free from smoke or dust, and using a cool-mist humidifier to ease breathing. Over-the-counter cough suppressants don’t help, and children should never be given aspirin due to the risk of Reye’s syndrome. Honey may soothe coughing in older children and adults, but never give honey to infants under one year.

Prevention

The most effective way to prevent pertussis is through vaccination.

• DTaP vaccine: Given to infants and young children at 2, 4, 6, and 15–18 months, with a booster at 4–6 years.
• Tdap booster: Recommended for preteens (11–12 years), adults who haven’t had one, and pregnant women during each pregnancy (between 27–36 weeks). This protects both the mother and her newborn during the baby’s first months.
• Adult boosters: Every 10 years, adults should receive a Td or Tdap booster to maintain protection.

Good hygiene — such as handwashing, covering coughs and sneezes, and wearing a mask if ill — can also help reduce spread. If someone in your household is diagnosed with pertussis, close contacts may be prescribed preventive antibiotics, especially if they include infants, pregnant women, or people at high risk.

Outlook

Pertussis can last for weeks or months and may take up to three months for a full recovery. Although most people recover completely, infants face the highest risks of complications, making vaccination and prevention especially important. Adults and teens usually recover without long-term problems, though the cough can be exhausting and disruptive.

Takeaway: Whooping cough is a preventable but potentially dangerous disease. Vaccination with DTaP and Tdap is the strongest protection — not only for yourself but also for vulnerable infants who are too young to be fully vaccinated.