Bordetella pertussis : an agent not to be forgotten in Qatar

Background: Pertussis (whooping cough) is a vaccine-preventable disease caused by the bacterium Bordetella pertussis that is spread by airborne respiratory droplets. Clinical symptoms vary from infants to adults and are most contagious before the onset of symptoms. Infants are at the highest risk of infection, especially before they are old enough to receive at least two doses of pertussis-containing vaccine. There have been no indigenous cases of pertussis in Qatar since 2010 until 2018, due to free pertussis-containing vaccines under the National Immunization Schedule of Qatar, with coverage consistently above 95%. Two cases were reported in 2016 but were found to be imported. In 2019, 20 infants were reported as suspected pertussis to the Health Promotion and Communicable Disease Control (HP-CDC), Ministry of Public Health (MOPH), Qatar; of them, five were laboratory confirmed as pertussis. Objective: This study aimed to describe the five confirmed cases of pertussis reported to HP-CDC, MOPH, Qatar, between January 1 and December 30, 2019. Summary of Cases: All five confirmed pertussis cases were under one year old, and three were boys. All except one were immunized-for-age, and three had not received any doses of pertussis-containing vaccine and in none of the cases had the mother received tetanus, diphtheria, and acellular pertussis (Tdap) vaccine during pregnancy. All infants were born in Qatar, and two were Qatari nationals. Conclusion: There may be a possibility of re-emergence of pertussis in Qatar. Active immunization and coverage maintenance are the best tools to prevent re-emergence. Undiagnosed and untreated pertussis cases are potential sources of infection. The partial or unimmunized groups may be significantly at risk, especially during infancy and before reaching the age to complete the three primary doses of diphtheria, tetanus, and pertussis vaccines. Focus on increasing awareness among those providing antenatal care, regarding the importance of Tdap vaccination during pregnancy, is necessary.