Whooping Cough Vaccine Protection ‘Wanes’
Pertussis vaccine effectiveness was only significant during the 10 years following vaccination
The resurgence of pertussis, known as whooping cough, has occurred in several high-income countries, including the USA and Canada.
Pertussis is a highly contagious infectious disease caused by Bordetella pertussis.
Recent studies have linked the increase in ‘whooping cough’ cases to the ‘waning’ of immunity from acellular pertussis vaccines.
A new study published on April 6, 2019, reported the pertussis vaccine's effectiveness (VE) was significant during the 10 years following vaccination, but the VE then decreased rapidly.
Moreover, this study reported whooping cough immunity was not fully restored after an adolescent dose at 14–16 years of age.
These researchers estimated vaccine effectiveness against pertussis was:
- 92% in 2–3-year-olds
- 90% in 8–9-year-olds
- 49% in children 12–13 years of age
Further data showed the VE following the teenage booster:
- 76% in 14–16-year-olds
- 78% in those 16–22 years old
- children who were up-to-date with the immunization schedule, VE declined from 87% during the first year to 74% after 8 or more years following their last vaccine dose
This was a case-control study of 1,335 cases statutorily reported to public health in Ontario and occurring between January 1, 2009, and March 31, 2015.
Previously, new research suggested the bacteria which causes the disease has mutated, which may be a cause for the pertussis vaccine’s waining.
This means the current acellular pertussis (aP) vaccine formulations may no longer be a perfect match for the ‘shifted’ bacteria.
The Centers for Disease Control and Prevention (CDC) Pertussis Working Group reported on March 13, 2019, that such genetic changes may be ascribed to vaccine-driven, immune selection.
Following the introduction of vaccines against pertussis, the burden of the disease dramatically decreased.
Globally, the World Health Organization estimated as many as 142,512 pertussis cases with an estimated 89,000 related deaths in 2015.
The most recent peak in US pertussis cases was in 2012 when 48,277 cases were reported to the Centers for Disease Control and Prevention (CDC).
In the USA, 2 vaccines help prevent whooping cough: DTaP and Tdap.
Children younger than 7 years old get DTaP, while older children, teens, and adults get Tdap.
Vaccine discount coupons can be found at GoodRx.
Vaccines can cause side effects, which should be reported to a healthcare provider or the CDC.