Whooping cough, popularly called whooping cough in medical language - pertussis; manifests itself as a respiratory disease that is highly contagious and is caused by the bacterium "Bordetella pertussis". This infection is characterized by a respiratory tract infection, so there is a moderate to severe coughing episode lasting about weeks or months. However, infants and young children are at risk; however, the disease can still affect humans of all ages. Therefore, the disease derives its name from its characteristic "whooping" sound that is produced during rapid breathing after a coughing attack.
The disease usually begins with symptoms of the common cold, such as a runny nose, mild fever and sometimes coughing. After this period, the cough will worsen and many attacks may include vomiting and fatigue, as well as breathlessness due to exhaustion. The episode ends with a spectacular high-pitched, hoarse sound. Some do not develop whooping cough - for example, adults and those who have been vaccinated - but the cough, with its severity and persistence, is still the hallmark of the disease.
The pertussis pathogen is contained in the respiratory droplets of an infected person. It can spread easily to these close contacts; thus, it is possible to spread through families, schools or community places, where outbreaks occur most frequently. The usual incubation time is 7 to 10 days, and in some situations it can extend up to 21 days. An infected person is highly contagious during the early stages of the disease, often as soon as the cough begins, which makes the disease milder and more difficult to diagnose and prevent early.
It is caused by the pathogen Bordetella pertussis, a gram-negative, aerobic coccobacillus, which produces several toxins that contribute to the symptoms of the disease. Pertussis toxin is particularly important because of the immune-suppressive and inflammatory effects it has in the respiratory tract. Filamentous hemagglutinin and fimbriae also promote the bacteria's ability to adhere to the ciliated epithelial cells lining the respiratory tract and damage normal function in the cells, impairing the clearance of mucus and bacteria from the body.
The typical clinical trajectory of whooping cough is divided into three phases: the catarrhal phase, the paroxysmal phase, and the convalescent phase. The catarrhal phase lasts between one and two weeks and displays very mild symptoms at first, similar to a cold-like respiratory infection. However, during this initial period individuals will be very contagious without knowing they have the disease, while the next stage is the paroxysmal phase, which lasts several weeks and is marked by bursts of increasingly intense coughing. Often, they cause cyanosis, vomiting, and fatigue. The final stage, called the convalescent phase, implies a gradual decrease in all symptoms, so that it resolves on its own, leaving behind a residual cough for several weeks or months.
Whooping cough is a disease that causes health problems mainly for unvaccinated people, infants, and people with weakened immune systems. It can lead to complications such as pneumonia, dehydration, weight loss due to difficulty eating or drinking, and fractured ribs due to severe coughing. In infants, it can lead to life-threatening conditions such as respiratory arrest, seizures, and encephalopathy. Preventive measures against these consequences require early detection and treatment.
Both clinical observation and laboratory testing are commonly used in the diagnosis of whooping cough. A physician generalizes the history of characteristic and increased intensity of cough to suspect pertussis. Laboratory confirmation is collected using polymerase chain reaction (PCR) testing of nasopharyngeal swabs for the genetic material of Bordetella pertussis. Culturing and serological methods may also be used; however, PCR is the preferred and frequently used method because it is faster and more sensitive. Chest X-rays may be used if pneumonia or other complications are suspected.
Whooping cough is treated primarily by antibiotics, which eliminate the bacteria and help reduce the risk of transmission. Macrolides, azithromycin, and erythromycin are considered the most useful drugs as preferred antibiotics. Early administration of antibiotics during the catarrhal phase significantly reduces the severity and duration of symptoms, but effectiveness is lost once the paroxysmal phase is reached. It is important to provide supportive care such as hydration, rest and oxygen therapy in severe cases. They are essential in symptom management and prevention of complications.
Thus, vaccination is the mainstay of prevention against whooping cough. Vaccination with diphtheria and tetanus vaccines (DTaP) is effective in preventing the disease, mostly in children and for adolescents and adults, combined to form Tdap. Vaccination of infants, children, pregnant women and even close contacts of newborns has been a preventive measure against tetanus and diphtheria. However, waning immunity requires boosters at intervals for effective protection, especially in adults and adolescents.
Pertussis outbreaks have spread to many countries around the world and emphasize that high vaccination coverage and public health interventions must be maintained. These factors include low vaccination rates, waning immunity, and the re-emergence of vaccine-resistant Bordetella pertussis strains. Surveillance, awareness programs, and focused vaccination programs are critical to help control the spread of pertussis and, at the same time, protect vulnerable populations.
Pertussis represents a very serious respiratory illness caused by Bordetella pertussis and involves a persistent cough without stopping, causing a strange sound most of the time. It poses a considerable risk to the health of infants, but even more so to individuals who have not been vaccinated. Early diagnosis and provision of effective treatment along with preventive measures including vaccination are essential to manage the disease and minimize its impact on public health. Long-term control and prevention of such diseases will also require continued research and public health efforts to address waning immunity and vaccine-resistant strains.
