December 10, 2011 5 Comments
Presently Australia is experiencing a major whooping cough (pertussis) epidemic.
It’s been in epidemic proportions since 2008-2009. Interestingly 2007 was the third lowest year on record since notification became compulsory in 1991. 2009 was a notably bad year for pertussis. A major contributor to epidemics is low pertussis vaccination rates, as evidenced here, in the UK and the USA. Adult boosters are crucial in combating this.
Contrary to certain claims this epidemic is not due to the pertussis vaccine nor does it demonstrate inherent flaws in the efficacy of pertussis vaccination. We do know that the age at which pertussis vaccine induced immunity wanes has fallen. Exactly how this relates to the acellular vaccine vs the older whole cell vaccine and the bordetella pertussis bacteria, is complex. However, there is a basic account here, along with interviews on The World Today and some musing on the error in blaming vaccine efficacy.
California experienced a severe epidemic in 2010, confirming the problem with waning immunity. Often used as a trick by antivaccination lobbyists to claim “the vaccinated” mostly get pertussis, the reality is different. Vaccinated individuals can catch a much milder form of pertussis, yet unvaccinated patients experience severe illness, disability and even death. In this same article, under Waning Pertussis Immunity Comes as No Surprise Dr. Carol Baker writes in part:
The California epidemic was caused by underimmunization of some children, and by waning immunity in fully vaccinated children. It showed that we are not where we need to be to have herd immunity. The 2010 California outbreak caught everyone’s attention.
Recently in Australia claims were made about pertussis vaccine inefficacy on ABC which I looked at here. It’s a favourite theme of the AVN and if you’re keen to look at exposing tactics it has popped up here, and here involving abuse of WHO data whilst we even have a cameo from Viera Scheibner pushing much the same at about the 6:45 mark.
Regarding adult boosters of 1 dose, the NCIRS fact sheet on pertussis (below), backed by citations states [my bold]:
The efficacy of the pertussis components of dTpa vaccines administered to adolescents and adults is inferred from the serologic results obtained in infants immunised with paediatric DTPa in pertussis efficacy trials. For both dTpa vaccine formulations, the immune responses to all pertussis vaccine antigens in adolescents and adults 1 month after a single dose of dTpa were non-inferior to those of infants after 3 doses of DTPa.
A large clinical trial in adolescents and adults demonstrated overall vaccine efficacy against confirmed pertussis of 92%, and a clinical trial in adults demonstrated prolonged immunogenicity from a single dTpa booster dose, with pertussis antibodies remaining above pre-booster dose levels in 85% of participants for 5 years after immunisation.
It’s widely known pertussis boosters are or have been available free in many states and territories. This may vary between new parents, family members, foster parents and other adults as a view of this Immunise Australia page suggests. It’s probably best to contact your own health department or just call the local GP. So, how are adults going keeping up with boosters?
According to the Australian Government 2009 Adult Vaccination Survey:
An estimated 11.3% of Australians aged 18 years and over had received a pertussis vaccination as an adult or adolescent. Uptake was substantially higher among parents of infants aged less than 12 months old (51.5%).
Hmmm. It seems we can certainly lift our game. If you haven’t had a booster for 4-5 years please get one. If you’re an adult likely to be in contact with a newborn then definitely get one.
If you’re none too happy with the conduct of the antivaccination lobby the single greatest effect you can have against them is to get a pertussis booster. As adult herd immunity rises less infections will be passed to at risk children, non-immunised infants, other adults and there will be less notification in total. This will serve to deflate the claim that rising diagnoses are ipso facto proof that childhood vaccination is a failure.
The Australian Vaccination Network wrongly compares 95% pertussis vaccination rates in young children (11% of diagnosed age groups) with 11.3% of adult vaccination (89% of diagnosed age groups). Then claim total population infection (100% of all diagnoses) is due to ineffectiveness of childhood vaccination alone.
For example Meryl Dorey compares vaccination rates of small children – which are around 95% – with diagnosis across all age groups – which include adults at around 11.3% – to secure high notification levels. Of the 18 age groups making up notifications only 2 correspond to the 95% vaccination rate. 16 age groups fall outside that at which immunity begins to wane (the 11.3% vaccination rate). Including numbers of infants too young to have completed pertussis vaccination, it’s clear Dorey’s figures come most primarily from the unvaccinated and non immune.
Today, ABC AM interviewed a parent who lost a four week old to pertussis. She said:
I hadn’t had a booster and the most heart-wrenching thing for us is that we were not warned, there was meant to be a yellow warning sticker go on [her] blue book in the hospital, we didn’t get one.
We didn’t know about adults requiring boosters, nor did any of the adults around us, none of our family or friends knew and we also didn’t know that the area I was living in was in the grip of an epidemic.
Well, now we do know. There’s really no excuse if you’re able to be vaccinated.
Please get your pertussis booster ASAP.