Cases of whooping cough are witnessing a noticeable spread, especially in Europe, which has prompted health authorities and scientists to call for vigilance and vaccination after this disease was caused by bacteria that cause severe infections in the respiratory system.
What is whooping cough?
Whooping cough (or pertussis) is caused by a type of bacteria called Bordetella pertussis. It causes a highly contagious and long-lasting respiratory infection.
Repeated and prolonged coughing attacks are the main symptom of the disease.
The infection is transmitted through the air very easily, and the disease is spread from person to person by inhaling infected droplets. That is, droplets emitted by the patient, and this occurs within the family or in places where a number of individuals gather. Each patient transmits the infection to an average of about 15 other people. The incubation period lasts on average from 9 to 10 days.
Then the clinical symptoms of the disease begin with a catarrhal phase, followed by a paroxysmal cough, and ending with a persistent cough and a sniffle.
Whooping cough may pose a danger to infants, as the severe form may be accompanied by shortness of breath and deterioration of one or more organs.
Vulnerable people (chronic respiratory patients, immunocompromised people, pregnant women) are more at risk.
Whooping cough rarely leads to deaths, but it may occur especially among unvaccinated infants.
How much has infections increased?
Before the Covid-19 pandemic, bacteria caused epidemic peaks approximately every 3 to 5 years.
Whooping cough has reappeared since the end of 2023 in several countries, in Europe and on the opposite side of the Atlantic Ocean. Epidemic peaks can last for several months.
More than 32,000 cases of whooping cough were recorded in 30 European countries in the first three months of 2024, and this number is already much higher than in the entire year of 2023 (more than 25,000 cases), according to the European Center for Disease Prevention and Control.
Major epidemic peaks were reported in Croatia, Denmark and the United Kingdom, and significant increases in cases in Belgium, Spain and Germany.
In France, the number of cases rose from 495 in all of 2023 to more than 5,800 cases in the first five months of 2024, according to the National Reference Center for Whooping Cough at the Pasteur Institute.
Director of the National Research Center, Sylvain Brice, said in an interview with Agence France-Presse that it is a “strong recovery” in the number of infections, noting that “France has not witnessed a similar volume of cases for at least 20 years.” He noted that “this stage of the epidemic is still ascending,” expecting a significant increase in the number of infections during the Olympic Games in Paris.
What are the reasons?
Scientists believe that this increase in infections is the result, as for other germs, of ceasing to take preventive measures against the (Covid-19) pandemic.
The specialist from the Pasteur Institute said, “We were expecting a sharp rise in whooping cough, which is a periodic disease, knowing that the last peak in France dates back to 2018. The Covid-19 phase delayed the return of whooping cough, and now it is coming back strongly.”
Although a rebound in infections was expected in 2021-2022, health measures related to the COVID-19 pandemic may have contributed to reducing transmission.
It is also likely that the current increase is linked, according to this expert, to a decrease in herd immunity since the recent episodes of outbreaks of infection.
Other scientists also believe that one of the reasons may also be the low level of vaccination against whooping cough in some population groups during the (Covid-19) pandemic.
What about vaccination?
Vaccination is the best way to protect.
The groups most at risk are infants under two months who cannot yet be immunized due to their young age, and adolescents and adults who have lost vaccine protection, often due to the unavailability of boosters, or due to illness.
Although the number of whooping cough cases has decreased significantly since the vaccine was approved, vaccination, like the disease, does not provide lifelong protection against infection.
Specialists stress that vaccinating pregnant women is crucial to protecting their future children.
Since the vaccine does not completely protect against transmission, it is possible for a person to be carrying the bacteria, without showing symptoms, and to subsequently transmit the disease. Hence the need to be vigilant when around young children.
What is the treatment?
After pertussis is diagnosed, sometimes by polymerase chain reaction (PCR) testing, “treatment of pertussis aims to eradicate the pertussis bacterium and consists of administering antibiotics as early as possible,” according to the World Health Organization, especially macrolide antibiotics.
This aims to quickly reduce the possibility of transmitting infection and enable the patient to return to society after a few days of treatment.
Hospitalization is strongly recommended for children between 0 and 3 months of age, especially for cardiac and respiratory monitoring.
Antibiotic resistance should be noted, although it is still rare. “We are beginning to detect strains resistant to macrolides, which can complicate patient care, with sometimes serious consequences for newborns,” said expert Sylvain Press.