Nicole Guiso

Macrolides are the first-line treatment against pertussis. The high prevalence of macrolide-resistant Bordetella pertussis (MRBP) strains reported in China is concerning. MBRP might be underestimated in other countries. Looking for the mutation causative for MRBP in retrospective studies conducted in Madagascar and Cambodia, we found no MRBP.

Pertussis vaccination in pregnancy is a safe and highly effective strategy to protect young infants against severe pertussis, but cases continue to occur. In November 2023, the authors of this paper met to discuss difficulties faced by pertussis vaccination programs in pregnant women in Europe, and the need and potential for new vaccines. We summarize current pertussis epidemiology, the status of pertussis vaccination in pregnancy in Europe, followed by a summary of the meeting on benefits of pertussis-only vaccines and pertussis vaccines with improved immunogenicity, including a review of available vaccines. Ongoing surveillance and registers documenting vaccine uptake in pregnant women are important to monitor changes in pertussis epidemiology and estimated effectiveness of maternal pertussis vaccination programs in individual countries. While current programs have been effective, Tdap or Tdap-IPV combined vaccines are not the ideal choice but are the only vaccines available for pertussis immunization in pregnancy in Europe. Pertussis-only vaccine would avoid exposing women to unnecessary tetanus and diphtheria boosters in every pregnancy. Recombinant pertussis vaccines with higher immunogenicity could prolong passive immune protection against pertussis in young infants.

Background: Amidst a global resurgence of diphtheria cases with numerous outbreaks recorded worldwide since 2000, a better understanding of this vaccine-preventable disease's circulation is needed. Methods: We retrospectively analyzed sera from 2 sero-epidemiological cross-sectional studies in Madagascar and Cambodia on fully primo-vaccinated 3- to 15-year-olds. Using enzyme-linked immunosorbent assay (ELISA) and seroneutralization (Vero Cell TNT) for the 3- to 8-year-olds with low ELISA titration values (6 years postvaccination. Results: Seven hundred forty-five children in Cambodia and 949 children in Madagascar were included. Our results show significantly more unprotected children among the 5- to 6-year-olds than among the 3- to 4-year-olds, with 41.1% (39/95) vs 26.7% (27/101; P = .03) in Cambodia and 21.4% (27/126) vs 8.0% (9/113; P < .01) in Madagascar. In Cambodia and Madagascar, respectively, 27.8% and 20.7% of the participants whose primary vaccination was performed >6 years earlier were seropositive, suggesting diphtheria infection. In both countries, we observed a higher rate of infected children when the last vaccine injection had been received 7–8 years or 11–12 years earlier vs 5–6 years earlier. Conclusions: Our data show that the disease is present at high levels in Cambodia and Madagascar and that the national recommendation—primary vaccination—is not sufficient: Booster doses appear necessary at around 6 years of age and for adolescents, as recommended by the World Health Organization.

Background and Aims Bordetella pertussis and B. parapertussis are the causative agents of whooping cough, a re-emerging infectious disease in spite of reasonable vaccination coverage. Specific diagnostic tools were applied for the first time in a Tunisian prospective study in order to get an estimation of the prevalence of Bordetella infections, and to evaluate their use to determine the epidemiological characteristics of these infections in Tunisian infants. Methods Between 2007 and 2011, a total of 626 samples from 599 infants aged < 1 year with and without pertussoid cough were investigated for the presence of B. pertussis/parapertussis using culture and real-time PCR (RT-PCR). When possible, patients’ household contacts provided nasopharyngeal aspirates (NPAs) for RT-PCR detection of B. pertussis/parapertussis or single-serum samples for anti-PT IgG quantification. Results All except 1 NPA were negative by conventional culture whereas PCR gave positive signals for 126 specimens (21%): B. pertussis, B. parapertussis and Bordetella spp. were detected in 82, 6 and 4% of the samples, respectively. The simultaneous presence of B. pertussis and B. parapertussis was noted in 8% of the cases. The prevalence of Bordetella infection was 20%. Most of these cases corresponded to patients younger than 6 months old who received < 3 doses of pertussis vaccine. Among the household contacts enrolled in the study, mothers were the likely source of infection in 4 cases. Conclusions This study showed that pertussis is still prevalent in Tunisia and the disease remains a public health problem affecting not only infants but also adults.