Whooping cough (pertussis) is caused by bacteria. It is highly contagious. Globally, whooping cough is one of the most common respiratory infections. The whooping cough pathogen produces poisons that damage the mucous membranes lining the airways. In Germany, children and adolescents, in particular, are affected by whooping cough, but frequently also adults. Babies, who do not yet have vaccination protection, are especially at risk.
The whooping cough pathogen is transmitted from person to person as an airborne infection. Coughing, sneezing or talking produces tiny droplets from the nasal cavity and throat: by these the bacteria can be spread up to a metre through the air, where they can then be inhaled. Virtually every contact between an unprotected person and an infected person leads to infection.
The pathogens may also be carried by a healthy person with vaccination protection for a short while. While the immunised person does not fall ill, they can nonetheless pass on the bacteria to others.
With young people and adults, the coughing phase often features more prolonged coughing, without the typical coughing fits. This atypical progression makes it difficult to recognise whooping cough. A risk of infection is then appreciably higher if the illness of the infected person is unidentified.
The first symptoms usually appear between 9 and 10 days (and sometimes 6 days or up to 3 weeks) after infection. Patients are already contagious a few days before symptoms appear. The risk of contagion is highest at the first stage (in the “cold” phase), before the typical coughing fits begin. Patients stay contagious for around 3 weeks after the coughing starts. Babies may continue to excrete pathogens for longer. If whooping cough is treated with an antibiotic, the transmission window is shortened to around 5 days after starting treatment.
For new-borns, whooping cough can be a life-threatening illness. Around two thirds of new-born patients will need to be admitted to hospital. New-borns can only obtain specific defences against whooping cough if their mothers are vaccinated several weeks prior to the birth. This ‘passive immunity’ protects the children in the first few weeks of their life until they can be immunised themselves.
As protection from vaccination only lasts a few years, older children, adolescents and adults can also catch the disease, although symptoms are usually much milder. However, they in turn form a dangerous source of infection specifically for infants and toddlers, as well as older persons and persons with underlying illnesses.
A vaccination for whooping cough is available. The German Permanent Vaccination Commission (STIKO) recommends vaccination:
Persons of any age can catch whooping cough again after recovering from an illness. Immunity after illness lasts approx. 7–20 years and approx. 5 to 7 years after immunisation.
Your local health authority can provide you with further advice. Since whooping cough infections must be reported, they will also have the latest information and be very experienced in dealing with the disease. More (specialist) information is also available online from the Robert Koch Institute (www.rki.de/pertussis). For information on how vaccinations stop infection, visit the website set up by the Federal Centre for Health Education (www.impfen-info.de).