PPIB and pertussis: In this context, recent data have shown that anti-B. pertussis antibody concentrations decreased significantly in women of childbearing age in the first year of the COVID-19 pandemic, in the context of mitigation measures and in the absence of recent boosting with pertussis vaccines, indicating that B. pertussis pre-existing immunity declines in the context of the absence of circulation of B. pertussis [126].