Need some info on Human Papilloma Virus and Cervical Cancer? Everything and more than you ever wanted to know

This is NOT a humourous posting or especially entertaining - I wrote this paper to present information on HPV-infection and the vaccination and tried my best to present it without bias and basically leave my opinion out of it.
The posting has at this point received two excellent comments that will force me to amend it - this is going to happen over the next weeks, just to make sure the information remains scientifically up-to-date.



1. Introduction
2. Human Papillomavirus (HPV) and Vaccination
2.1. HPV and Associated Diseases
2.1.1 What is HPV and what diseases does it cause?
2.1.1 How do you get HPV and how can you avoid infection?
2.2 Epidemiology of HPV
2.2.1 What is the risk of getting HPV
2.2.2 What is the risk of infection for girls under 12
2.3 The HPV vaccine Gardasil
2.3.1 What is Gardasil and how does it work?
2.3.2 What about the criticism of the vaccine I've heard about?
2.3.3 Are there other problems with vaccination?
2.4 Teenage Sexual Behavior
2.4.1 Are girls really at risk before they are even teenagers?
2.4.2 How can I reduce my daughter's risk of infection without vaccination?
3. Discussion
3.1 Benefits of the vaccination
3.2 Risks of the vaccination
3.3 Limits of the vaccination
4. Conclusion: How would I decide?
Bibliography

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1. Introduction

On June 8th, 2006 the FDA licensed Gardasil, a new vaccine by the pharmaceutical company Merck, to prevent cervical cancer, precancerous genital lesions and genital warts caused by some strains of human papilloma virus (HPV)(OODP 2007). HPV is one of the primary causes of cervical cancer and genital warts. The HPV vaccine Gardasil is approved for use in females age 9 to 26. The federal Advisory Committee on Immunization Practices (ACIP), a committee of the Center for Disease Control and Prevention (CDC), recommended that the new vaccine be administered routinely to girls 11 to 12 years of age.

The discussion on HPV vaccination quickly developed into a public health argument and mandatory vaccination, regulated on a state not federal level, came to be seen as the logical conclusion by many. In 2007, at least 24 states and Washington D.C. introduced legislation to specifically mandate HPV vaccine as a condition for school entry (NFSL 2007). In California, the bill A.B.16 was introduced to the legislature in December 2006 to require HPV vaccination of all 6th grade girls but has since been withdrawn for further consideration (CA Legislature 2006).

Judging from the heated exchanges in the blogosphere and print and online editorials no middle ground exists between mandatory vaccination and absolute opposition. The noisiest opponents of the vaccination are evangelical Christians claiming it encourages sexual promiscuity and subverts parental authority, staking the moral high ground claiming an infringement on their parental rights (Cole 2007). They are joined by anti-vaccination activists who routinely claim the inherent danger of any vaccination and conjure their usual threats of potential terrible long-term side effects (National Vaccine Information Center 2007). On the other hand, too many supporters of mandatory vaccination seem to consider parents’ concerns as proof of ignorance and backwardness without addressing some of the very real concerns that beset parents faced with worries about efficacy and safety of the vaccine (Whelan 2006). The discussion about HPV vaccination has veered away from the medical facts into political terrain. No longer is the discussion about the merits or risks of vaccination but rather whether HPV vaccination should be mandatory and enforced by the states. Unfortunately parents’ worries do not get addressed dispassionately any longer.

The ongoing debate leaves parents of prepubescent daughters in the difficult situation of having a new and effective vaccine at hand but having to decide on their actions without necessarily having access to unbiased information, since many of the available sources do not give equal space to arguments on both sides of the issue. This report will give parents a honest overview of the facts on HPV infection as well as HPV vaccination. It will give statistical data on prevalence and risk of infection as well as data on sexual behavior in teenagers. It will evaluate the true risk of a HPV infection and the benefits of vaccination and discuss approaches to face the question: “Should my daughter be vaccinated?” The report tries to supply data that will allow a family to make their decision based on facts.

2. Human Papilloma Virus (HPV) and Vaccination

2.1 Human Papilloma Virus and Its Diseases

Papilloma viruses are a group of DNA-based viruses that infect the skin and mucous membranes of humans and a variety of animals. The virus is highly species specific and does not infect other species. HPV is not related to Herpes or HIV virus (Gearhart 2007).

2.1.1 What is HPV and what diseases does it cause??

At the moment about one hundred eighteen papillomavirus types have been completely described, a higher number of presumed new types have been detected (de Villier 2004), and more than 100 human papilloma viruses (HPV) are defined. The virus was named after the most common types which cause benign skin warts, also called papillomas. HPV is generally associated with the development of "common warts" which are transmitted environmentally or by casual skin-to-skin contact.

Non-genital HPV

About 10% of the adult population suffers from warts, the most common disease caused by HPV. HPV types 1, 2, 3, 4, 7 and 10 cause common, plantar, and flat warts which are usually found on the skin of the body (including the soles of the feet). They do not progress to cancer in people with a healthy immune system but typically regress on their own within weeks or months (60 to 70 percent clearance in 3 to 24 months)(Rinker 2007).

Sexually transmitted HPV

Around 40 of the HPV types are sexually transmitted; they infect the genital area of men and women including the skin of the penis, vulva (the area outside the vagina), or anus, and the linings of the vagina, cervix, or rectum as well as the upper respiratory system. Most people who become infected with HPV will not have any symptoms and the body will clear the infection on its own. In about 90 percent of women, cervical HPV infection becomes undetectable within two years; the body clears the infection on its own. Most people who have a genital HPV infection do not know they are infected. Most genital HPV types live in the skin or mucous membranes and generally cause no noticeable symptoms (Gearhart 2007).

Low-Risk HPV

Some sexually transmitted HPV’s are so-called “low-risk” viruses and may cause mild Pap smear abnormalities or genital warts. Genital warts are single or multiple growths or bumps that appear in the genital area. The HPV types 6 and 11 are responsible for about 90% of genital warts. Both symptoms (Pap abnormalities and warts) have a low risk to progress to cancer. About 0.5-1 million cases of genital warts are diagnosed each year (Kazzi 2007). Both HPV type 6 and 11 are also suspected as agents in the development of vulvar cancer though this association has not been proven.

High-Risk HPV

13 HPV types (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, and 68) are called "high-risk" types because they can lead to the development of cervical cell anomalies and eventually to cervical cancer, anal cancer, vulvar cancer, head and neck cancers, and penile cancer as well as a type of throat cancer.

The body generally clears even high-risk HPV infections on its own within 2 years, but in some people the infection persists. Although only a small proportion of women have persistent infection, a persistent infection with "high-risk" types of HPV is the main risk factor for cervical cancer. Unattended, about 1% of women with genital HPV infections will eventually go on to develop cervical cancer. In most cases of cervical cancer high-risk types of HPV has been found in tissue samples. HPV infection is considered play at least a major if not a necessary role in the etiology of cervical cancer. Over 70% of cervical cancer is caused by HPV strains 16 and 18 (Garcia 2006).

2.1.2 How do you get HPV and how can you avoid infection?

Wart-causing HPV types are transmitted directly or indirectly by virus material from an infected person and are thus very difficult to avoid. Genital HPV types are sexually transmitted and can only be avoided by absolute celibacy.

Non-genital HPV

HPV types that cause warts are spread by both direct and indirect contact. The virus resists desiccation, freezing, and prolonged storage outside of host cells and can thus even be transmitted by touching a surface contaminated with virus material. Autoinoculation can also occur, causing the local spread of warts. Warts are a therapeutic challenge and often are recurring (Allen 2000).

The very mode of transmission makes avoidance of infection difficult.

Genital HPV

Anogenital HPV (both high- and low-risk) is fundamentally a sexually transmitted disease. It passes from one person to another through genital contact, actual intercourse is not necessary.

HPV infection can even occur in both male and female genital areas that are covered or protected by a latex condom, as well as in areas that are not covered. A recent study showed that constant use of condoms reduced the likelihood of infection by 70% (Winer et al. 2006). However, this means that even with constant use of condoms, about 30% of test subjects still were infected with HPV.

A long-term monogamous relationship is another way to reduce exposure, but remember that previous exposure of a sexual partner to HPV is very difficult to determine. Since HPV doesn’t usually cause any symptoms and any diseases caused by it tend to develop over a long time after infection, most infected people do not know that they have contracted an infection. Unless you live in a 100% monogamous relationship where neither partner had a sexual encounter before, you may get infected by your partner.

The only way to eliminate any risk of infection is to avoid any sexual genital and oral contact.

2.2 Epidemiology of HPV

Just about everyone can be infected with HPV. With over 100 human HPV types that infect the skin and the mucous membranes of the body, contact with an infected site is possible through many avenues. Sexual transmission is one of them, but direct or indirect transmission of virus material from an infected person is enough to get infected with wart-causing HPV types. More than 50% of sexually active people will be infected with anogenital HPV types in their lifetime (CDC 2005).

2.2.1 What is the risk of getting HPV?

The quoted statistics of HPV infection mentioned in the media vary wildly, with one review finding reported values anywhere from 14% to 90% (Revzina, 2005). The quoted numbers need a context that is usually not provided. The number of women that have ever been infected by any type is much higher than the number of women that are currently infected by one of the high-risk types because in most cases an individual’s immune system clears the infection within two years and thus will be found negative in the next test.

Body warts

Warts caused by HPV types 1, 2, 3, 4, 7 and 10 are estimated to affect approximately 7-12% of the population. In school-aged children, the prevalence is 10-20%. The warts usually regress on their own within 2 years. An increased frequency also is seen among immunosuppressed patients and meat, fish and poultry handlers (eMedince 2007).

Anogenital HPV types

Anogenital HPV types can be acquired by everyone who has sexual relations with another person. A direct correlation exists between anogenital HPV infection and measures of sexual activity, such as the age of first intercourse and the lifetime number of sexual partners (Kazzi 2008). In the heterosexual community, the risk of infection is slightly higher for females than for males while homosexual males have a higher risk of infection than the general population. HPV infection occurs at any age although rates of new infections are highest among college-aged women and men (Dunne et al., 2007).

A 2007 study found that during 2003–2004, at any given time, 26.8% of women between 14 to 59 were infected with at least one type of HPV (including those that are harmless). Of all high-risk types that cause cancer, 15.2% were infected. Of the four types prevented by the Gardasil vaccine, however, only 3.4% were infected (Dunne et al., 2007).

World

Approximately 630 million people of both sexes are infected with HPV worldwide, and a significant majority of women - 80 percent - will become infected by age 50. HPV infection is most common among young adults between the ages of 18 and 25. Every year nearly half a million cases of cervical cancer are diagnosed worldwide and more than 250,000 women die due to cervical cancer. Cervical cancer is the second most common cancer in women worldwide after breast cancer, and in developing countries, it is the leading cause of death by cancer. 80% of all cases of cervical cancer occur in low-income countries.

USA

In the USA HPV infection does not pose as high a risk for cervical cancer as in other parts of the world. In the United States, about 27% of all women between 14 and 59 test positive for HPV infection. The infection rate is highest in females at the beginning of their sexual activity, with nearly 50% of all 14 to 19 years testing positive. About 6 million new cases of genital HPV infection occur per year, with ¾ of them in 15 to 24 year olds. For college age females there is a cumulative incidence of HPV of 38.9% at 24 months, this means more than two thirds catch a HPV infection within 2 years of entering college (Dunne et al., 2007).

Despite these high numbers of infection, “only” about 14,000 women are diagnosed with cervical cancer each year and more than 3,900 women die in the USA each year from this disease. About 1% of all cancer deaths per year are due to cervical cancer. Just to put this number into perspective, the CDC statistical data report for 2003 states that 3,358 people died that year from malnutrition (Hoyert. 2003).

Prevention of Cervical Cancer

The introduction of Pap smears in preventive care is the main reason why the risk of cervical cancer is much lower than expected. Pap smears catch a high percentage of cervical cell abnormalities in women and careful medical evaluation and treatment usually follow, reducing the risk of development of cancer. In women who have already developed cervical cancer Pap smears often identify the cancer in earlier stages which increases the likelihood of a positive outcome of treatment. About half of the women in the USA who develop cervical cancer have never had a Pap smear (CDC 2005).

The risk of getting cervical cancer and dying varies for different groups in the USA. The toll of the infection is disproportionately high among minority women. Diagnosis of cervical cancer and mortality is about 1.5 times as high in Latina and African American women as in white women. The cause of this is not clear, but lack of access to health care is discussed as one of the reasons. The later cervical cancer is detected in a woman, the worse the expected outcome. Not even half of women of color have received recent screenings for cervical cancer and their risk for being diagnosed with cervical cancer late is accordingly higher.

2.2.2 What is the risk of infection for girls under 12?

The individual risk is very low since the vast majority of girls under 12 are not yet sexually active. It has also been shown that the 4 HPV types the vaccine Gardasil protects against are found in only 3.4% of all infected females between 19 and 59 (Dunne et al., 2007), so the risk of acquiring any of these HPV types is relatively low at any age group.

Infection by an older partner

Studies show, however, that girls who first have sex at a very young age (younger than 13) are more likely to have sex with a male who is about 5 years older. This behavior puts those girls at a higher risk of infection from a male that has been more exposed to infection himself (Westover 1996, Hegna 2004).

Infection with several types of HPV

Young girls that do get infected will generally be infected with only very few different types of HPV. The risk of infection with various types of HPV increases with the number of sexual contacts; the major age-group showing seroconversion for HPV-infection is 18-25, when the number of sexual contacts is highest, and not the very young age group.

Non-genital HPV-infection

Recent studies have shown that while teenagers are increasingly waiting longer to have sex and the age of first intercourse is increasing, other forms of sexual activity, being perceived as less risky, are on the rise. Oral sex is one of these activities. A new study found that some HPV strains that cause cervical cancer can also sharply increase the risk of certain types of throat cancer among people infected through oral sex (Khamsi, 2007).

2.3 The HPV Vaccine Gardasil

Gardasil does not protect against all HPV infections but only against those with 4 anogenital HPV-types that are most commonly causing genital warts and cervical cancer. Vaccinated women will still have to get yearly Pap smears for cancer prevention because they will not be protected against all virus types that cause cancer (Merck 2007).

2.3.1 What is Gardasil and how does it work?

Gardasil is a vaccine by the pharmaceutical company Merck that targets four strains of human papillomavirus (HPV). Those strains are called HPV-6, HPV-11, HPV-16, and HPV-18. The vaccine has proven nearly 100% effective in protecting against these strains in test subjects that had not been infected with them at the time of inoculation.

The efficacy of the vaccine was assessed in 4 placebo-controlled, double-blind, randomized phase II and III clinical studies that were performed to best clinical practices. The FDA has evaluated and approved of the study design and the results.

The vaccine has been tested in over 11,000 test subjects (ages 9-26 years) around the world, 1121 were between 9 and 15 years of age.

Protection against 4 HPV-Types

The main ingredients of the vaccine are purified inactive proteins that come from HPV types 6, 11, 16, and 18. The vaccine does not contain any DNA, only inactive protein, and is thus absolutely unable to cause an infection.

HPV-16 and HPV-18 account for about 70 percent of all cervical cancers. HPV-6 and HPV-11 account for about 90 percent of genital warts.

The vaccine also contains amorphous aluminum hydroxyphosphate sulfate, sodium chloride, L-histidine, polysorbate 80, sodium borate, and water for injection. These are standard ingredients in vaccines.

Gardasil is given in 3 injections over 6 months. Full protection is only achieved after the last injection. The shots can cause pain, swelling, itching, and redness at the injection site, and more generalized it can cause short-lived fever, nausea, and dizziness. So far, every indication is that Gardasil has only rare and minor side effects.

Target group

The vaccine is recommended for girls between 11 and 13 and can be given to girls as young as 9. For the best protection, girls should get the vaccine before they are sexually active. The reasoning behind this decision is that the vaccine is most effective in girls/women who have not yet acquired any of the four HPV types covered by the vaccine. Girls who have already been infected with one of the vaccination strains receive no benefit from the vaccination with this strain, but they are protected from infection caused by the remaining vaccine HPV types in the vaccine.

2.3.2 What about the criticism of the vaccine I’ve heard about?

In the discussion of Gardasil several criticisms keep coming up that are often not discussed in depth by the CDC or the National Cancer Society’s endorsement of the vaccine.

Size of test sample

One problem is the size of the test group. Only 1121 girls between 9 and 15 have been tested, and no numbers are given how many girls of each year of age were vaccinated. This makes it difficult to ascertain how the vaccine actually works in very young girls. The group of test subjects of an age under 12 is unknown and even the total of about 1100 is not large enough to justify a nation-wide vaccination program for all girls of 12 years.

However, it must be noted that the clinical studies do not show any difference in either efficacy or side-effects of the vaccine in any of the age groups, which strongly implies that there is no higher risk for young girls than for older girls.

Duration of vaccination protection

A second problem is that at this time the vaccinated females have been followed for only 9 months to generally 18 month, in some cases to 3 years. It is not yet possible to say how long the vaccination will protect a woman. It is possible that a girl vaccinated at 12 or younger might actually need a booster vaccination to keep her protection up before she ever gets sexually active some time later.

The study results so far show that vaccination in females under 15 causes a stronger antibody response than in females over 15 (Merck 2007). While this is no guarantee that the vaccination will last longer, there is no indication either a booster vaccination would be necessary within three years, which is the length of the available clinical observations so far. The phase IV clinical observations in patients are ongoing and more results will come out over time.

Long-term cancer protection

Another serious criticism is that the vaccination will reduce cervical cancer. Cervical cancer is a disease that very, very rarely hits young women (in 100,000 women in the 9-26 year old age group one would expect about 3-4 cervical cancer cases per year), and cervical cancer following HPV infection is usually a decades-long development. At present, the number of cases of cervical cancer is lowered mainly by preventive care in form of Pap smears that many women get regularly. The only certain statement that can be made at the moment is that vaccination protects against HPV infection. Merck actually did not (since that is impossible) test for reduction of cervical cancer but for CIN (cervical intraepithelial neoplasia) 2/3 and AIS (adenocarcinoma in situ) as surrogate markers. CIN 2/3 and AIN are necessary precursors to cervical cancer, in most cases, however, they do not lead to it. Gardasil is marketed as a cancer vaccine, yet at the present time no-one can say with absolute confidence if the vaccination will actually reduce cervical cancer cases or not. Since there are several cancer-causing HPV-types, it is possible that the long-term outcome might not be as positive as predicted, with presently rarer types of HPV filling the void left by the vaccine and increasing their cancer-causing potential.

Price

At $360 for one series of shots Gardasil is the most expensive vaccine in the market. For many families this expense is a serious hardship. At the moment it is impossible to say at which time a booster vaccination will be necessary, so it is a steep price. Parents also need to add the cost of three visits to the doctor to the cost of the vaccine. Merck is marketing the vaccine in Great Britain for £450 ($880).

2.3.3 Are there other problems with vaccination?

Ammonium adjuvant

The anti-vaccination critics like to point out that one of the ingredients of the vaccine, amorphous aluminum hydroxyphosphate sulfate, is an adjuvant that has not been tested for safety in humans. Aluminum hydroxide, which stimulates immune response, has been used for 80 years in vaccines such as those for hepatitis A and B, and for diphtheria, pertussis, tetanus, polio and meningitis. While aluminum adjuvants are not antigenic in themselves, they stimulate an immune response and increase the body’s response to a vaccine. Research indicates that high doses of aluminum salt may cause damage; the dosage in the vaccine however is much too low to be of concern. Most of the criticism of this kind is found on websites of extreme anti-vaccination groups (Janak 2007); their findings have not been backed by reputable researchers nor have they held up to peer-review.

Side effects in study

Another criticism of the HPV vaccination claims that the side effects have been underplayed by comparing the more serious side effects (dizziness etc) in two different placebo groups with the vaccination group. A closer inspection of the actual numbers finds, however, that the rate of more serious side-effects really is as low as stated. This criticism also overstates the severity of those side-effects which in the clinical studies have been temporary and limited, despite the critics’ claim that there are severe generalized problems.

Only 0.1% of the participants, just a few subjects (although the exact number is not given) in the studies dropped out because of side-effects.

By all accounts, you will feel this shot – nearly 84% of the participants mentioned pain as a side effect, over 10% respectively 35% more than of the control subjects. Anecdotal reporting of women getting shots seems to imply that the pain can be rather bad; this is a shot that hurts.

Swelling, itching and skin reddening 1 to 5 days after vaccination have been mentioned by about twice as many vaccinated subjects as by control subjects. But 94.3% of the vaccinated subjects described side effects as mild to moderate.

As far as the more serious side effects of fever, nausea and dizziness area concerned, the differences between Gardasil- and control subjects is very small: 10.3% of vaccinated subjects complained of fever compared to 8.6% of control subjects. For nausea (4.2% vs. 4.1%) and dizziness (2.8% vs. 2.6%) the difference is even smaller.

Swelling, itching, reddening, fever and nausea are common side effects found with the majority of vaccinations.

Several sites that are extremely critical of Gardasil mention the risk of autoimmune disorders brought on by the vaccination. This is not backed by numbers. A total of 9 vaccinated subjects out of 11,813 developed arthritic problems, in the control group of 9701 subjects 3 developed the same. These numbers simply do not allow any statistically valid conclusion about the risk for autoimmune side effects – the numbers are so small that it is dishonest to make this claim.

Long-term side effects

The Vaccine Adverse Event Reporting System (VAERS), a cooperative program for vaccine safety of the Centers for Disease Control and Prevention (CDC) and the Food and Drug Administration (FDA) is a post-marketing safety surveillance program and collects data about adverse events (possible side effects) that occur after the administration of US licensed vaccines. The VAERS database shows that as of February 17, 2007, some 9 months since its approval, 385 adverse event reaction reports were received. A number of symptoms were reported, with varying levels of severity. The most frequently reported reactions were pain of various types (89), fainting (55) and dizziness (41), fever (41), abnormal skin sensation (32), rash (33) and itching (31), vasodilation (19), headache (19), and vomiting (16) and Guillain-Barre Syndrome (8) (Guillain-Barre is a disorder that produces numb, weak limbs and, in severe cases, paralysis). Most of the patients with Guillain-Barre Syndrome were associated with receiving the meningitis vaccine Menactra at the same time.

The VAERS system only collects raw data for analysis of possible side effects of vaccines and does not establish causation; the reported incidents may or may not have anything to do with the vaccine; this connection can only be made statistically at a later date. Additionally, it is unknown how many people have been vaccinated with Gardasil and so calculate the risk of side effects in the whole vaccinated population (CDC 2007).

Undue influence on political decision making

From a different point of view Merck came under severe criticism for their strong lobbying to have Gardasil mandated by state legislatures. Bluntly put, they have too much to gain to be credible when it comes to endorsing the vaccine. Mandatory vaccination with Gardasil would guarantee a huge profit for the company – every girl would have to be vaccinated, and either insurances or the states would pick up the bill. Additionally, a company that produces a vaccine mandated by a state is shielded from civil liability. The federal vaccine liability program states that a company cannot be sued if something goes wrong that they could have anticipated. Potential liability rests with the government; victims who can prove that their injuries fall within certain scientifically established boundaries receive full compensation for economic losses.

Considering that a company’s main interest is profit, their lobbying makes sense while the information they disseminate might be taken with a grain of salt. However, Merck’s claims of the vaccines safety and efficacy have been backed by the FDA, the CDC and the National Cancer Society as well as independent researchers, and while some critics claim that these respected agencies are conspiring with Merck it is rather more believable that the critics are paranoid.

2.4 Teenage Sexual Behavior

If parents could be absolutely sure of their children’s behavior, then there probably would no need for vaccinating any girl under 15. However, parental surety and the reality of teens’ behavior are not always in alignment and however much parents might want to feel confident about their children’s behavior, everyday experience does not necessarily bear this out.

2.4.1 Are girls really at risk before they are even teenagers?

Girls will profit most from vaccination before they become sexually active to protect them completely from the 4 HPV strains covered by Gardasil. Girls who have already been infected with one of the vaccination strains receive no benefit from the vaccination with this strain, but they are protected from infection caused by the remaining vaccine HPV types.

Remember though, only 3.4% of all tested women between 14 and 59 were infected with one of the four types prevented by the Gardasil vaccine. (Dunne et al. 2007).

Vaccination dilemma

The problem with Gardasil vaccination is simply that to be most effective it needs to be given before a girl is at risk. This is of course true for any vaccination - they only do any good before we run into the infection. The main problem with HPV vaccination often is the perceived connection between the vaccine and sex, which generally is not a topic parents feel very comfortable with and often would rather disregard.

To give parents a general idea of the statistical risks for their daughters, the latest available statistics from the CDS in 2002 highlight the sexual behavior of teenagers (CDC, 2004):

Sexually transmitted diseases (STD) in teenagers

According to some estimates of the nearly 19 million cases of sexually transmitted diseases (HPV is NOT counted one of them but rather syphilis, gonorrhea etc.) about ½ (9 million) occur in the 15-19 age group.

Age at first sexual encounter

The age at first sexual activity has increased in recent years, but still 15% of all males and 13% of all females report having had at least one sexual encounter before the age of 15. In general, children who use drugs at a young age (alcohol and cigarettes) are more than twice as likely to have sex before 14 as those who don’t.

Non-voluntary sexual encounters

A more disturbing number is the cases of non-voluntary first sex. 18% of those who had sex before 14 reported that it was non-voluntary. Non-voluntary sex is not rape but defined on a scale, from “really wanted it” (which is voluntary) to “didn’t really want it to happen at the time”. This is basically a description of a girl browbeaten into having sex for reasons nothing to do with her, but rather perhaps with what her boyfriend wants.

Age-difference in sexual partners

About 74% of teenagers had sex with someone of the same age or up to 3 years older, only 8% had sex with someone more than 6 years older. This again points to a relatively low risk for infection in young teenagers – the risk of contracting HPV is obviously lower if the sex partner is very young himself and not likely to have been exposed to various HPV types themselves.

Girls who had their first sexual encounter under 14, however, were more likely to have a partner who was over 5 years older than they were and accordingly were at higher risk for infection (Westover 1996).

Casual sex

The same is true for the choice of partner – 75% of teenage girls had sex with someone they were “going steady with”. But 14 % admitted to having sex with someone they basically barely knew. This again is a risk factor in contracting a sexually transmitted infection – the less you know a sexual partner, the easier it is to pick up an STD.

2.4.2 How can I reduce my daughter’s risk of infection without vaccination?

As is often the case, honesty and communication are key.

Studies have shown that teenagers who waited longer before they had their first sexual encounter often come from close-knit families where the parents made their own opinions on sex clear and kept a close eye on their children’s friends and their behavior without being autocratic.

However, as any parent knows, this is a very fine line to walk and is not guaranteed to work in individual cases.

In short, there are only a few ways you can reduce exposure to HPV:

Abstinence from all forms of sexual relations that include any contact with genitals

Limit the number of sex partners

Choose a partner with few or none previous sex-partners

Always use condoms

3. Discussion

The biggest problem in the discussion of vaccination against HPV-infection is the manner of its transmission. The sexual component of infection makes the evaluation an emotional, not a scientific problem.

The fact that HPV is sexually transmitted makes parents uncomfortable because they would rather not think about their children having sex, especially at a young age. Parents concentrate not on the benefit of the vaccine (their daughters being protected against an infection), but on how the infection gets transmitted (their children having sex). If a vaccine came onto the market that could potentially cut lung cancer rates by 70% but it would have to be given to prepubescent children to be effective, everybody would make sure that their children get vaccinated.

The required childhood vaccinations include vaccinations against diseases that are nowadays rare in the US, like whooping cough or tetanus. Yet the majority of children are being vaccinated, despite the fact that those vaccines can have side effects in some children. Parents accept that the protective potential of the vaccine outweighs the risk.

3.1 Benefits of the Vaccination

Considering the number of cases of genital warts (0.5 -1 million new cases a year) and cervical cancer (14,000 new cases a year) the benefits outweigh the risks. Despite all the criticisms of Gardasil, there is at present no data that supports the claim that the vaccine is dangerous. The side effects are mostly slight and passing and the reports of serious side effects are not substantiated. Even if there are some long term side effects, their number will not be equal to the side effects of HPV infection.

Genital warts are both a physical and a psychological problem and although many cases clear on their own, they are often recurring. A 90% protection against genital warts is excellent in any light.

Even though cervical cancer is already at a low level in the USA and could be brought down even more if every woman received Pap smears, it still is a serious disease and could be reduced by 70% if the vaccine works as predicted. While there is some dissent in the medical profession if the promise of the vaccine will bear out as completely as predicted, the majority of medical experts worldwide believe in the value of the vaccine. A search in the scientific database PubMed shows that the positive evaluation of Gardasil is far more common than the critical one. Most of the scientists publishing their research are not tied to any company or organization and cannot be accused of slanting their data.

At its most callous, it is possible to perform a risk consideration: Genital warts, though relatively common, are not dangerous enough to justify vaccination with a new and untried vaccine with unknown long-term side effects.

However, with 14,000 new cervical cancer cases per year and about 3,900 deaths from it, the risk of a HPV infection is defined and relatively high. Based on the data available from the clinical studies and phase IV follow-up data so far it is clear that the same number of serious side effects is practically impossible. Even if (and these are utterly invented numbers) Gardasil were to be found directly responsible for 1 death in one million vaccinations and 10 cases of debilitating side effects, the risk of NOT vaccinating a girl is higher than the risk of doing so. And the numbers used in this expample are pure invention and not in any way likely to be true!

3.2 Risks of the Vaccination

The risks of the vaccination are low, but, as with all vaccinations, they exist. There is always the chance of an allergic reaction to a vaccination; in the case of a new vaccine, there is the possibility that your daughter might be the one who actually has a dangerous side-effect. This, however, is true for any vaccination and any drug people take.

On the other hand, your daughter definitely will be exposed to HPV once she starts having sex, and once the infection has taken place, nothing can be done to heal it.

Given the information at the present time, it is reasonable to assume that the vaccination will protect against the diseases caused by the HPV types that cause the majority of cervical cancers and genital warts. Infection with these strains is a real risk, not a potential one like the vaccination.

As mentioned in the previous chapter, a risk consideration of the vaccination compared to unchecked HPV infection with the 4 types the vaccine protects against shows that the risks are very low indeed. Any side effects that would kill nearly 4000 people a year and cause serious health effects in 14,000 (which is what the HPV infection does) would have shown up in the clinical studies.

This is not to say that there might not be more side effects than have been described so far. It only means that a girl’s likelihood for one of the side-effects is lower than for one of the long-term effects of the disease.

3.3 Limits of the Vaccination

HPV vaccination only protects against HPV -16 and HPV-18, which account for about 70 percent of all cervical cancers. This means that 30% of cervical cancer patients were diagnosed with cervical cancer that was not caused by the HPV types the vaccine protects against. The statistical risk for an individual of developing cervical cancer is reduced by 70% through vaccination, but not abolished.

An infection leading to genital warts cannot be healed, only treated. Quite often the warts come back and the patient needs another round of treatment. With a reduction of over 90% with the vaccine, this risk would be seriously reduced, but 50,000 to 100,000 cases of genital warts would still occur per year.

Like any woman, your daughter will have to get her yearly Pap smears to further reduce her risk developing cervical cancer.

4. Conclusion: How Would I Decide?

At the present time, I would let my daughter be vaccinated when she is at least 14. Since the full protection of Gardasil only sets in after 3 injections over 6 months this seems a sensible age. At that age there is a 1 in 8 chance that she might have sex, even if I thought she would not .

I would consider the protection she could gain against both genital warts and cervical cancer to outweigh the potential risk of the vaccination, and waiting longer might well expose her to one of the strains that she could be protected against.

If my daughter were younger than 14 I would wait until more data has been collected about side-effects of the vaccination. The numbers of reported incidents in the VAERS database continues to rise and I expect to be able to get better data on the potential side-effects of vaccination within one or two years, especially since Gardasil is closely watched by experts and critics.

I would definitely not want a daughter under 12 be vaccinated at this time. The actual risk of infection is practically zero at that age and I would consider it prudent to give the vaccine some more observation and follow-up time to mature and be evaluated on more people.

With a young daughter I would keep up with the ongoing research and decide on vaccination depending on the outcome of a few more years of observation of the side effects of Gardasil, I would have her vaccinated either at a younger age of 10 to 11, or perhaps only at 16.

I would not allow the doctor to give my daughter other vaccinations together with Gardasil, but only the HPV vaccine alone, to reduce the stress to her immune system.

Since there is a fair amount of anecdotal evidence that some girls faint shortly after the injection, I would accompany her and make sure she received the shot lying down on a cot and I would stay with her there for at least 15 minutes after the injection.

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