Whooping cough is the layman term used for the infectious disease called pertussis. It is a highly contagious infection that can quickly spread from infected individuals to others through infected aerosol or mucus droplets. The name of this infection is based upon its characteristic symptom in which coughing is followed by a sound of ‘whoop’ as you inhale a second breath, although it may not be present in all infected individuals. Vaccination for its causative agent has highly reduced the prevalence of this infection.
The causative agent for whooping cough is Bordetella pertussis, a gram-negative bacteria. The bacteria enter through the nasal cavity by means of infected aerosols from another infected person. They multiply and release toxins that disrupt the normal functions of the inner lining of the nose and pharynx. This leads to the characteristic symptoms of this infection. Usually, it is limited to the upper respiratory tract but may progress towards lungs in infants or unvaccinated individuals.
A major risk factor for the development of whooping cough is the absence of a vaccine or incomplete vaccination. Children were a primary target of the pathogenic organism, but vaccination reduced the number of infected individuals significantly. That is why children below five years of age who have not been vaccinated yet and infants are at the highest risk of this infection. Coming into close contact with an infected individual is another significant risk factor. Therefore doctors, nurses, and people working at healthcare facilities are at risk if they have not been vaccinated. Due to systemic diseases, genetic diseases, medications, or treatments, individuals with weakened immune systems are also at high risk. The presence of other respiratory tract diseases such as asthma, chronic obstructive pulmonary disease, etc., can also increase the risk of developing whooping cough. Whooping cough or pertussis can occur at any age in an unvaccinated individual, but infants and children are more frequently affected. Around 5000 to 7000 cases of whooping cough have been reported yearly in the United States. This infection affects both males and females equally.
The symptoms of whooping cough progress in three stages. The first stage is called the catarrhal stage, in which the infected person experiences a low-grade fever, coryza (runny nose, stuffed nose, absent or decreased sense of smell), and mild cough. If it is occurring in an infant, they may have sleep apnea as well. This stage persists for one to two weeks. It is followed by the second stage, called the paroxysmal stage. This is the worst stage of this infection, where the person develops paroxysmal coughs (recurrent or intensifying cough), which results in labored breathing. As the person tries to inhale after a fit of cough, a high-pitched sound or characteristic ‘whoop’ is noticed. Extreme fits of coughing may also cause vomiting, shortness of breath, and mild blue discoloration of the face. This stage persists for almost two to ten weeks. The third stage of this disease is called the convalescent stage, where the symptoms start to fade off, but coughing fits may occur occasionally. This stage lasts for almost one to four weeks. Overall whooping cough is a long-term disease that can last several months in infected individuals.
The persistence of whooping cough may lead to severe symptoms, which include sleep apnea, pneumonia, pneumothorax, rib fractures, vertebral artery dissection, hernias, otitis media, pulmonary hypertension, seizures, subdural hematoma, and encephalopathy. These complications are uncommon in adults. If these complications develop in an infant, a child less than five years of age, or an elder with a weak immune system, they can lead to mortality if not treated immediately.
The diagnosis is generally made based on symptoms alone. A detailed history involves the onset of disease, duration, severity, and persistence of symptoms. Long-term fits of coughing followed by whooping sound or vomiting are a characteristic diagnostic sign. Although variable symptoms may occur, the diagnosis is confirmed by a nasopharyngeal swab for a culture test or PCR to identify the pathogenic organism accurately.
Other diseases that present with similar symptoms as whooping cough include asthma, chronic obstructive pulmonary disease, influenza, common cold, pneumonia, sinusitis, bronchiolitis, tuberculosis, pulmonary embolism, congestive heart failure, gastroesophageal reflux disease, etc. It is important to differentiate whooping cough from other diseases of the respiratory tract that cause coughing, fever, and runny nose.
The primary method for the treatment of whooping cough is antibiotics. Symptomatic care is required along with antibiotic dosage to reduce the severity of symptoms. Staying inside, drinking warm soups or broths, and rest are recommended till symptoms are better. Active or passive smoking is avoided during the recovery period as it may trigger a coughing fit.
Antibiotics are prescribed for the cure of whooping cough. The regimen is decided by your doctor based on your age and other factors. Commonly prescribed antibiotics for this infection are azithromycin, erythromycin, and clarithromycin. If you are resistant or intolerant to any of these antibiotics, trimethoprim-sulfamethoxazole is indicated.
If the infection is diagnosed early, the intake of prescribed antibiotics can lessen the symptoms from developing into severity. Adults with a healthy immune system usually recover well. Infants or adults with a weak immune system are at risk of developing severe complications if the disease is not addressed and treated on time.
Pertussis vaccine is the best method to prevent the development of this infection. It is usually given along with vaccination for two other severe diseases; diphtheria and tetanus. The vaccine is therefore labeled as the DTaP vaccine. It is given in 5 doses, starting from infancy to 6 years of age. A booster dose is also recommended in adults and pregnant women. Other prevention methods include keeping a safe distance from an infected person, washing hands regularly with soap or hand-wash, and using an alcohol-based sanitizer. The infected person should also try to limit visiting crowded areas to avoid spreading this disease.
Our clinical experts continually monitor the health and medical content posted on CURA4U, and we update our blogs and articles when new information becomes available. Last reviewed by Dr.Saad Zia on May 11, 2023.