Whooping Cough Epidemic in Casablanca in 2024

Whooping cough is a respiratory infection primarily caused by a bacterium called Bordetella pertussis. It is a cyclical disease occurring every 3 to 5 years. This infection leads to high morbidity and mortality among infants too young to be vaccinated. In Morocco, as in many countries, three epidemic peaks have been observed despite high vaccination coverage. The aim of this study was to analyze the epidemiological, clinical, biological, and progression profiles of children hospitalized for whooping cough.

This prospective study included 30 infants hospitalized for whooping cough over one year (from January 1 to December 2024). Data was collected using a preestablished data collection form.

The average age was 2 months and 26 days, ranging from 31 days to 1 year and 7 months. Vaccination status analysis revealed: 13 infants were unvaccinated (43.33%), 15 were partially vaccinated for their age (50%); however, only 2 were fully vaccinated (6.6%). A source of contamination was identified in all cases, with mothers being the primary source of contamination (18 cases, 60%), followed by siblings (3 cases), fathers (3 cases), grand-parents (3 cases), and cousins (3 cases). Complicated cases were dominated by secondary infections (18 infants, 60%), severe apnea (12 infants), and pneumonia (1 infant). Blood tests showed lymphocytosis between 8,000 and 10,000/mm³ in 7 infants (23.3%), between 10,000 and 20,000/mm³ in 12 infants (40%), and above 20,000/mm³ in 1 infant (3.3%). PCR testing of nasal secretions was positive in 21 out of 29 cases (72.4%). Chest X-rays were normal except for 5 infants with alveolar opacities. All patients received a 3-day course of azithromycin, and their mothers were also treated. The outcome was favorable for 28 patients, while 2 were transferred to intensive care for severe apnea and convulsive status. One death was recorded.

Whooping cough remains a significant public health issue. Morocco is currently experiencing an epidemic resurgence. Prevention relies on booster vaccinations for adolescents and young adults, as well as infants at the age for vaccination. Maternal vaccination during pregnancy is currently the most effective strategy to protect unvaccinated newborns.