and it is the under-1 year-olds that are the most severely affected with nearly 1% of the infected dying from it.
The incubation period is between 4 – 21 days and during this time it is highly contagious with up to 80% of the unvaccinated catching it.
The main reservoir of infection is in adolescents and young adults (whose personal immunity has worn off). But for all of us (even if we get the native infection) the antibody level (hence our immunity to the disease) wanes over a couple of years.
The horrible disease is that of a lung infection with thick sticky mucus. After a few days of a ‘cold-like’ illness, the bouts of coughing start. Such is the irritation of the mucus and the difficulty in coughing it up, the patient can cough hard and repeatedly, emptying their lungs of air, before a violent inhalation causes the characteristic ‘whooping’ sound (pronounced ‘hoop’, by the way).
Adults have been known to break a rib or rupture a disc in the neck with the violence of the coughing fit.
Babies however most often just present with stopping breathing (‘apnoea’), and when they contract the infection, they can get many complications including pneumonia, seizures, brain swelling and even death.
How can we protect our vulnerable babies?
Since the late 1990’s we’ve had the acellular vaccine which is remarkably safe and effective. Unfortunately it doesn’t generate enough antibodies in babies under 6 weeks of age. To protect them after that they need a full course of vaccinations (at 6 weeks, 4 and 6 months), and then get boosters at 12-18 months and before entering school.
There are two strategies to protect them before this age:
1) Vaccinate mothers during the pregnancy between 27 and 36 weeks gestation.
This works in a couple of ways.
It immunises the mother so she won’t catch the infection and pass it to her baby.
It also sends her anti-whooping-cough antibodies across the placenta to her foetus. These antibodies last a few weeks and protect the baby until the time of vaccination.
2) ‘Cocooning’. This means vaccinating everyone who comes into contact with the baby in the first weeks: parents, grandparents, siblings, and friends who want to visit the baby. A single booster is sufficient, such as ‘Boostrix’ (which also gives a boost to diphtheria and tetanus antibody levels too).
Nevertheless, due to the waning immunity in your blood it is appropriate to get another booster shot even if you had one 2-3 years before with another pregnancy.
The acellular vaccine has been shown to be completely safe to mother and baby during pregnancy.