Summary

 Introduction and Causes

    Pertussis, commonly known as whooping cough, is a highly contagious bacterial infection of the respiratory tract caused by the bacterium Bordetella pertussis. It is characterized by severe and prolonged coughing fits, often accompanied by a characteristic "whooping" sound as the individual struggles to breathe in after coughing. The disease primarily affects the airways, leading to inflammation and excessive mucus production, which can result in significant respiratory distress, especially in infants and young children. Pertussis can have serious complications, including pneumonia, seizures, encephalopathy, and even death, particularly in vulnerable populations such as infants who have not yet completed their primary vaccination series. Vaccination is the most effective preventive measure against pertussis, and early diagnosis and treatment with antibiotics can help reduce the severity and duration of symptoms and prevent the spread of the disease to others.

    Pertussis is caused by the bacterium Bordetella pertussis, which attaches to the cilia of the respiratory epithelial cells and releases toxins, causing inflammation and characteristic coughing spells. The disease spreads through respiratory droplets when an infected person coughs, sneezes, or talks, with individuals being most contagious in the early stages. Factors such as incomplete vaccination, waning immunity, high population density, limited healthcare access, and genetic variation of the bacteria contribute to its transmission. Environmental factors like diet and smoking may alter the gut microbiome and impact the immune response, while public health measures like maintaining herd immunity and monitoring global travel are essential to control its spread.

Signs and Symptoms

    Pertussis progresses through three stages: the catarrhal stage, the paroxysmal stage, and the convalescent stage. In the catarrhal stage, lasting 1-2 weeks, symptoms resemble a common cold, including mild cough, runny nose, sneezing, and low-grade fever, making diagnosis challenging. The paroxysmal stage, lasting 1-6 weeks or up to 10 weeks, is marked by severe coughing fits, a characteristic whooping sound, vomiting after coughing, exhaustion, cyanosis, and apnea in infants. The convalescent stage, lasting 2-3 weeks or longer, involves gradual recovery with a milder persistent cough that can continue for weeks or months. Infants and young children may present with apnea, feeding difficulties, and cyanosis, while older children and adults often experience a milder illness with a prolonged cough without the whoop. Complications include secondary bacterial infections like pneumonia, hospitalization, and severe coughing leading to rib fractures.