Friday, May 01, 2015

The science on HPV vaccination

First of all, a disclaimer; my children--the oldest 16--have not had the HPV vaccination yet for a simple reason; they are at low risk for sexual activity, and I'd like to wait until (a) they're more at risk for having sex and (b) even more data is in on the safety of the vaccine.  It's interesting to note that the vaccine has also been improved since the doctors first started offering it, and it now covers about 90% of HPV virii known to cause cervical cancer.  Not to gloat, but it's a good move. 

That said, here is an article about the study that finds, allegedly, that HPV vaccination is not linked to risky sexual behavior or promiscuity.  Summarized, they found that 4 of 1000 recipients of the vaccine had had an STD in the year before receiving the vaccine, and 6 of 1000 recipients had an STD in the year afterwards.  In contrast, those not receiving the vaccine had suffered an STD in the year before 3 of 1000 times, and after vaccination suffered an infection 4 of 1000 times.

The researchers do an interesting trick; instead of processing the overall numbers (say 600 vs. 400 infections among 100,000 teens in each group), they contrast the increases in STD infection as a % increase (50% vs. 35%, and we're not accounting for the second significant digit yet) instead of a comparison of the raw rates.

Now this makes some sense, as the incoming difference--.4% vs. .3%--is also statistically significant. Most likely, parents who felt their children might be promiscuous are getting their kids vaccinated.  That leads to a number of interesting questions, like what is the Pareto of diseases?  I would assume far fewer vaccinated children get HPV--does that mean a large portion of infections are bigger deals like herpes or (God forbid) HIV?

But the gorilla in the room is actually the overall rate.  CDC data indicate that most become sexually active in their late teens and contract 4 STIs over the next 20 years or so, --which would be a 20% annualized infection rate, not a .4-.6% infection rate.  In other words, the study is most likely of kids in their early teens or before, and thus had little chance of measuring the real risk of higher sexual experimentation after Gardasil was administered. 

In other words, yet another study that almost seems designed to come up with the standard narrative.  Your tax dollars at work, I guess.  Sexual behavior studies on kids who still think the opposite sex has cooties.


Hearth said...

One of the big reasons I choose not to have my children vaccinated for HPV is that there are so many HPV viruses, of which the vaccine only works on a few, the most common.

Is it at all unlikely that the HPV viruses that were 9th, 10th, and 11th in line behind the ones that now cause most cervical cancer (because they're the most common) will step up and become the ones that cause cancer 10 years from now, or 20 - inflicting cervical cancer on all those girls who *thought* they were covered?

And we won't even go into the side effects, known and unknown. Thank you, I prefer not to have my children used as laboratory rats.

Bike Bubba said...

Can't totally blame you--and until the CDC and others decide to actually carry the experiment forward for another decade, we're not going to have good numbers on whether people respond to a "make sex safe" vaccine by fornicating more--and ironically extending the number of diseases to be feared.

Kinda like Americans responded to antibiotics curing syphilis and genorrhea with the Sexual Revolution, extending the number of STIs to be feared from 2 to about 30. As we said in junior high, "Smooth move, Ex-lax."