HPV in the News: A Review of the Basics

HPV in the News:  
A Review of the Basics

You never know when or which topic in science will become a hot topic in politics, but when science and politics mix, the facts usually take a beating.  This is not because politics sets out to wage war on facts, but rather that politics always has a goal in mind, and it typically is happy to twist a few facts to reach that goal.

We have seen this all in play during the recent explosion of interest in the HPV vaccine by those some politicians vying to become their party's nominee to be president.  The controversy surrounds a 2007 executive order as governor by one of the candidates mandating that all middle school girls in the state be immunized against HPV infection.  Other candidates reacted strongly to that decision in a recent debate, and suddenly HPV immunization leapt to the headlines.  Large numbers of people began registering their anger at the idea that government could force someone to be immunized, and bristled at the idea that families could be forced into decisions that could promote promiscuity.

Given the furor over HPV, we thought it would be timely to take a step back from the political excitement and think about just what this virus is, what the immunization does, and how to make a good choice for your family.

What is HPV?
HPV stands for human papilloma virus.  This is the virus that causes all warts.  The word papilloma is the Latin way to say wart.  So the HPV is the virus that causes warts in humans.  

The HPV is different sort of virus.  Most viruses make you sick, but with one exception, HPV does not.
All infections with HPV cause an infection isolated to the one spot the virus has landed.   At that spot the skin is goaded into making more skin, causing a lump of skin material to form, the lump that we call a wart.  That lump of material, with one exception, causes no harm.  Often the virus can sit in the skin without any lump appearing, but with lump or no lump, the virus can sit in its spot under the skin for a very long time, sometimes for decades.  It looks like it can sit there for such long times precisely because it is very quiet about its business.  Often not spreading to other spots in the skin, and really not doing much where it sits.

Consider how strikingly different this is from the usual virus, say the virus that causes the common cold, the rhinovirus.  Once the rhinovirus lands in your nose, it starts a real fire.  It burns off the lining of the nose, and in  rapid sequence goes on to burn the lining of the throat, all the sinuses, and then the entire lung.  The burning only stops once all the linings are burnt.  Luckily for us, the burn is very shallow, so it is not dangerous, but it causes all the suffering of a cold- fever, feeling lousy, achiness, cough, and a river of mucus wherever the virus has been- nose, eyes, throat, and lungs.  The whole infection causes an uproar in the body with a big response from our immune system that kills the invader and ends the infection.  The whole drama is over in 1-2 weeks.

HPV does none of that.  As we noted, it does not spread well, wherever it sits it causes little harm, and it can stay in its quiet, isolated spot for decades, not weeks.

There is one exception to this peaceful portrait of HPV.  That is the ability for infection with HPV in the area of the cervix to start a sequence that can end in cancer.  The cervix is the neck-shaped end of the uterus that lies at the top of the vagina.  HPV infection of the cervix by certain subtypes of HPV, can start a process that allows cells there to start growing in a disorganized fashion, and sometimes that can end up with a cancerous tumor called cervical cancer.

It is worth repeating that HPV infection is not rare.  Essentially every single person will come into contact with the skin HPV's.  The skin HPV's are spread by simple contact, and appear to be a nearly universal experience.  The genital HPV's spread by sexual contact, but are nearly as common, causing infection in as many as 75% of all humanity.  As such HPV is, by far, the most common sexually transmitted disease (STD).

So HPV causes three types of warts.  The common warts of the external skin.  Genital warts in men and women.  And the special genital warts of the cervix that can become cancer.  Since each type is caused by a separate type of HPV, an immunization against one type of HPV will protect against the infection that type causes.

Of course, only the HPV that causes serious disease, the subtypes that can lead to cervical cancer, has been targeted with an immunization that can prevent HPV infection.  That means the HPV shot only prevents infection with the HPV's that cause infection in the cervix of the uterus, not the ones that cause common skin warts.

This is a smart choice.  After all would one rather have a shot that prevents harmless skin warts, or one that prevents a type of cancer that kills more young women in the world than any other?

What is the HPV Immunization?

What does the HPV shot try to do?   Prevent cervical cancer
Of the many types of HPV that cause infection of the cervix and that can then lead to cancer, the HPV immunization prevents infection from the HPV's that are most likely to lead to cervical cancer.  That is not all HPV's and it not all the HPV's that cause cervical cancer.

So the first thing to say about the HPV immunization is that it does not protect against all HPV infections and cannot prevent all cervical cancer.  But it does protect against the HPV infections that are responsible for roughly 70-80% of all cervical cancer.   Not a bad start.

Does the HPV shot work?  Yes
The next question is how well HPV immunization works.  The answer is that it works very well.  If you get HPV immunization before you are exposed to cervical HPV, that is before sexual activity begins, it will block infection with the HPV subtypes in the shot.  And it looks like it lasts.  Since the HPV's are so widespread, people get exposed to them for a very long time and this acts like a booster for the shot, helping it provide protection for many, many years.

Is the HPV shot safe?  Yes
As those familiar with Advanced Pediatrics know, we take do not allow any representatives of the drug industry to be in our office and accept no materials from them, all in effort to be sure when asked about their products, that we can offer the most trustworthy observations that science can provide, as free as possible from market influences.

It is with this commitment and approach in mind that we took a look at the facts of how safe this vaccine is.

The data are very strong and compelling that this is a safe vaccine.

The list of possible side effects are limited those seen with any shot- irritation, allergic reactions, fever, headache, and fainting.  That's about it.

Like with any intervention, however, when upsetting events happen after the intervention, one cannot help but believe the intervention caused it. This is the power of guilt by association.  A good example would be getting a haircut and then right afterwards getting into a car accident.  The accident did immediately follow the haircut, and so is definitely associated, but did the haircut cause the accident, clearly not.
Just so, there have been stories circulating that a person became mentally impaired after getting this shot, but there is no evidence that this shot causes any sort of mental impairment.  The impairment may have started on the day of the shot, but there is no reason to believe the shot caused it.

A wide body of study has looked carefully at whether the HPV immunization causes serious problems, and the observations are strong, consistent, and reassuring, the HPV immunization does not cause serious problems.

How to be immunized against HPV?
Immunization to prevent HPV infection takes three shots.  The second dose has to be 1-2 months or more after Dose 1, and the third dose 6 months or more after Dose 1.

It is best to be immunized before you get exposed to HPV, meaning before sexual activity begins.  If people are immunized in middle school or early high school, that seems to provide the best timing.

Keep in mind that human papilloma viruses (HPV's) can cause three types of infection in people- common skin warts, genital warts, and cervical warts.  Only the cervical wart infection can lead to cancer.  And that is why the HPV immunization only protects against the HPV's that cervical wart subtypes.

This is good to remember, because it introduces a difference in benefit between boys and girls getting HPV immunization.  Boys can only get two of the HPV infections mentioned, skin and genital wart infections.  So even if a boy gets an infection with a subtype of HPV that can cause genital warts, that virus cannot physically ever lead to cervical cancer, boys do not have a cervix.   Girls, of course, can and do get all three type of HPV infections.

As a result, if a girl gets the HPV immunization, she may prevent developing cervical cancer someday.  No boy will ever have that benefit.

So why immunize boys?  For the same reason we immunize everyone for rubella (German measles).  Rubella is a very harmless infection for children and adults, but deadly and deforming to the developing fetus.  We actually never immunize those really at risk for rubella, the fetus.  Instead, we immunize everyone else, all children and adults who need it.   That immunization offers essentially no benefit to those immunized, but since we all agree to be immunized, no fetus can be exposed.  This strategy has led to the nearly complete disappearance of all fetal rubella infections, a stunning triumph.

Just so with immunizing boys against HPV.

Remember, as many as 75% of all humanity, is infected with genital HPV.  It is literally everywhere.
Boys carry it as much as girls.  So it does help to immunize all girls, but it is not enough to prevent all the cervical cancer that we can.  If boys get immunized too, it greatly strengthens the defence against these HPV infections.

So we recommend boys get immunized, knowing that they will never gain the benefit of cancer prevention, but knowing that if they do get immunized it will help prevent cervical cancer in half of humanity. And, the boys will have fewer genital warts, offering some benefit.

American presidential politics have thrusted HPV immunization into the nation's spotlight.  As is to be expected, the discussion has promoted the temptation to throw facts out and let strong feelings carry the argument.

But when it comes to your child's health, it makes sense to take a step back, a bit of a breath, and try to base decisions on facts.

The salient facts are these:
  • The human papilloma viruses (HPV) cause warts on our skin, genitals and the cervix of the uterus.
  • HPV infects nearly all of us.   The skin types are likely present in all people at some time.  About 75% of people,  men and women, are infected with genital HPV.  The genital HPV in women is the major cause of cervical cancer.
  • HPV immunization can prevent infection with the subtypes that cause cervical cancer in women.
  • The HPV vaccine works and is safe.
  • Sadly, politics is having some of its way with science, obscuring facts, trying to raise fears, hopefully the facts can help you keep your focus on keeping your children healthy.
Dr. Arthur Lavin

*Disclaimer* The comments contained in this electronic source of information do not constitute and are not designed to imply that they constitute any form of individual medical advice. The information provided is purely for informational purposes only and not relevant to any person's particular medical condition or situation. If you have any medical concerns about yourself or your family please contact your physician immediately. In order to provide our patients the best uninfluenced information that science has to offer,we do not accept samples of drugs, advertising tchotchkes, money, food, or any item from outside vendors.

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