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Human papillomavirus (HPV)

Ask the Experts: Diseases & Vaccines

Human papillomavirus (HPV)

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Human papillomavirus (HPV)
Disease Issues Contraindications and Precautions
Vaccine Recommendations Vaccine Safety
Scheduling and Administering Vaccines
Disease Issues
How common is human papillomavirus (HPV) infection?
HPV is the most common sexually transmitted infection in the United States. Currently, more than 20 million men and women in the United States are infected with HPV, and more than 6 million are estimated to become infected each year. HPV is most common in young women and men in their late teens and early 20s. By age 50, at least 80 percent of sexually active women will have acquired HPV infection.
How serious is disease caused by HPV?
HPV infection can lead to cervical cancer in women as well as to other anogenital cancers that can affect males or females. Cervical cancer is diagnosed in more than 12,000 women each year in the United States each year and causes 4,200 deaths. Seventy percent of cervical cancers are caused by HPV types 16 and 18, which are included in both licensed HPV vaccines. HPV types 6 and 11 also cause over 90% of genital warts in men and women.
Vaccine Recommendations Back to top
Please provide more information about the two HPV vaccines, Cervarix (GSK) and Gardasil (Merck). What are the differences between them?
Cervarix is an inactivated bivalent vaccine (HPV2) that protects against HPV types 16 and 18. Gardasil is an inactivated quadrivalent vaccine (HPV4) that protects against HPV types 16 and 18, and also against types 6 and 11, which are human papillomaviruses that cause genital warts.
What are the CDC recommendations for use of HPV vaccine?
ACIP recommends that all males and females ages 11 through 12 years be routinely vaccinated with a 3-dose series; either HPV2 (Cervarix) or HPV4 (Gardasil) may be used in females, and only HPV4 (Gardasil) should be used in males. HPV vaccination is also recommended for females through age 26 years and males through age 21 years who have not completed or begun a 3-dose series. In addition, vaccination is recommended for men age 22 through age 26 years who 1) have sex with men or 2) are immunocompromised as a result of infection (including HIV), disease, or medication. Ideally, HPV vaccine should be administered before potential exposure to HPV through sexual contact. The vaccination series can be beginning as young as age 9 years at the clinician's discretion.
Both HPV vaccines should be given as a 3-dose schedule, with the second dose given 1 to 2 months after the first dose and the third dose 6 months after the first dose. The minimum interval between the first and second doses of vaccine is 4 weeks. The minimum interval between the second and third doses of vaccine is 12 weeks. The minimum interval between the first and third doses is 24 weeks. Whenever possible, use the same brand of HPV vaccine for all doses in the series given to females. In situations when that's not possible, use the second HPV brand to complete the series. It is not necessary to start the series over. For more information, see the ACIP recommendations from CDC at www.cdc.gov/vaccines/pubs/acip-list.htm.
Please describe the new recommendations for the use of HPV4 vaccine in males and explain how these new recommendations differ from the previous ones.
ACIP recommends routine vaccination of males age 11–12 years with HPV4 (Gardasil, Merck) administered as a 3-dose series. The vaccination series can be started beginning at age 9 years. Vaccination with HPV4 is recommended for males age 13 through 21 years who have not been vaccinated previously or who have not completed the 3-dose series. Males age 22 through 26 years may be vaccinated with HPV4.
ACIP recommends that immunocompromised males who have not been vaccinated previously or who have not completed the 3-dose series receive routine vaccination with HPV4 through age 26 years.
Men who have sex with men (MSM) are at higher risk for infection with HPV types 6, 11, 16, and 18 and associated conditions, including genital warts and anal cancer. ACIP recommends that MSM who have not been vaccinated previously or who have not completed the 3-dose series receive routine vaccination with HPV4 through age 26 years. Previously, ACIP had issued permissive recommendations for HPV4 use in males age 9–26 years for the prevention of genital warts.
To obtain a copy of the new recommendations, which were published in MMWR in December 2011, see www.cdc.gov/mmwr/preview/mmwrhtml/mm6050a3.htm.
Is use of HPV vaccine covered under the Vaccines For Children (VFC) program?
Yes. VFC-eligible females, ages 9 through 18 years, can be given either HPV2 (Cervarix) or HPV4 (Gardasil); VFC-eligible males, ages 9 through 18 years, should be given HPV4 (Gardasil).
Are pap smears still necessary for women who receive HPV vaccine?
Yes. Vaccinated women still need to see their healthcare provider for periodic cervical cancer screening. The vaccine does not provide protection against all types of HPV that cause cervical cancer, so even vaccinated women will still be at risk for some cancers from HPV.
Do women and men whose sexual orientation is same-sex need HPV vaccine?
Yes. HPV vaccine is recommended for females and males regardless of their sexual orientation.
Will patients who have already had genital warts benefit from receiving Gardasil?
A history of genital warts or clinically evident genital warts indicates infection with HPV, most often type 6 or 11. However, people with this history might not have been infected with both HPV 6 and 11 or with HPV 16 or 18. Vaccination will provide protection against infection with HPV vaccine types the patient has not already acquired. Gardasil (HPV4) protects against HPV vaccine types 6, 11, 16, and 18; Cervarix (HPV2; GlaxoSmithKline) protects against HPV 16 and 18. Providers should advise their patients/clients that results from clinical trials do not indicate the vaccine will have any therapeutic effect on existing HPV infection or genital warts. It is important, however, that patients receive all 3 doses of HPV4 vaccine to get full protection from genital warts.
If a patient has been sexually active for a number of years, is it still recommended to give HPV vaccine or to complete the HPV vaccine series?
Yes. You should not withhold HPV vaccine from people who are already sexually active. Ideally, patients should be vaccinated before onset of sexual activity; however, patients who have already been infected with one or more HPV types still get protection from other HPV types in the vaccine that have not been acquired.
I read that HPV vaccination rates are still low. What can we do as providers to improve these rates?
Results from the Centers for Disease Control and Prevention's 2012 National Immunization Survey-Teen (NIS-Teen) indicate that HPV vaccination rates in girls age 13 through 17 years failed to increase between 2011 and 2012, and the 3-dose coverage rate actually declined slightly during this period. Just over half of the girls age 13 through 17 years had started the series that they should have completed by age 13 years. Only about one-third of girls this age had completed the series. In 2012, the first year HPV vaccine was routinely recommended for boys, 20.8% of boys age 13 through 17 years had received one dose and only 6.8% had received all three recommended doses. A summary of the 2012 NIS-Teen survey is available at www.cdc.gov/mmwr/pdf/wk/mm6234.pdf, page 685.
Providers can improve uptake of this life-saving vaccine in two main ways. First, studies have shown that missed opportunities are a big problem. Eighty-four percent of girls unvaccinated for HPV had a healthcare visit where they received another vaccine such as Tdap, but not HPV. If HPV vaccine had been administered at the same visit, vaccination coverage for one or more doses could be nearly 93% instead of 54%. Second, the 2012 NIS-Teen data show that not receiving a healthcare provider's recommendation for HPV vaccine was one of the five main reasons parents reported for not vaccinating daughters.
CDC urges healthcare providers to increase the consistency and strength of how they recommend HPV vaccine, especially when patients are age 11 or 12 years. The following resources can help providers with these conversations. For more detailed information about HPV vaccination strategies for providers, visit www.cdc.gov/vaccines/who/teens/for-hcp/hpv-resources.html.
Scheduling and Administering Vaccines Back to top
What is the recommended schedule for administering HPV vaccine?
Both HPV vaccines should be administered in a 3-dose schedule, with the second dose administered 1 to 2 months after the first dose and the third dose 6 months after the first dose. The minimum interval between the first and second doses of vaccine is 4 weeks. The minimum interval between the second and third doses of vaccine is 12 weeks. The minimum interval between the first and third doses is 24 weeks.
If a dose of HPV vaccine is significantly delayed, do I need to start the series over?
No, do not restart the series. Just pick up where the patient left off and complete the series.
To accelerate completion of the human papillomavirus (HPV) vaccine series, can doses be given at 0, 1, and 4 months?
No, there is no accelerated schedule for completing the HPV vaccine series. You should follow the recommended schedule of 0, 1-2, and 6 months.
CDC recommendations state that the minimum intervals for HPV vaccination are at least 4 weeks between doses #1 and #2, and at least 12 weeks between doses #2 and #3. This adds up to a total of 16 weeks between doses #1 and #3. But the recommendations also say that there must be a minimum of 24 weeks between doses #1 and #3. This doesn't make sense to me.
When administering HPV vaccine, you must meet ALL the minimum intervals. For example, if you give dose #2 at a minimum interval of 4 weeks after dose #1, you must wait 20 weeks to give dose #3 in order to meet the 24-week minimum interval between #1 and #3. Determination of these minimum intervals was based on extensive discussion with the manufacturers and on data from the HPV clinical trials. For detailed information on minimum ages and intervals, see table 1 as published in CDC's "General Recommendations on Immunization" at www.cdc.gov/vaccines/pubs/ACIP-list.htm
If a patient's vaccination history indicates she received the third dose of HPV vaccine earlier than the recommended minimum interval of 24 weeks, should she be given a fourth dose?
Maybe. If the 3-dose series was given with minimum intervals of at least 4 weeks between dose #1 and dose #2, AND at least 12 weeks between dose #2 and dose #3, do not repeat any doses. If the third dose was given at less than 12 weeks from dose #2, repeat dose #3 at least 12 weeks after the invalid dose.
I work with university students and many of them miss coming in on time for their next dose of HPV vaccine. What's the longest interval allowed before we need to start the series over?
No vaccine series needs to be restarted because of an interval that is longer than recommended (with the exception of oral typhoid vaccine in certain circumstances). You should continue the series where it was interrupted. If the HPV series is begun when the university student is age 26 or younger, it can be completed after the student turns 27. It's important to rely on the actual recommendations, not urban legends or guesswork. All ACIP recommendations can be accessed at www.immunize.org/acip. ACIP's "General Recommendations on Immunization" are especially useful: www.cdc.gov/mmwr/PDF/rr/rr5515.pdf
Is it recommended that patients age 26 years start the HPV vaccination series even though they will be older than 26 when they complete it?
Yes. HPV vaccine is recommended for all women through age 26 years and also may be given to men through that age. So, the 3-dose series can be started at age 26 even if it will not be completed at age 26. The series should be completed regardless of the age of the patient (i.e., even if the patient is older than 26). In certain situations, some clinicians choose to start the 3-dose HPV series in patients who are older than 26 years. This, however, is an off-label use.
We inadvertently gave HPV #1 to a woman who didn't know she was pregnant at the time. How should we complete the schedule?
If the vaccine was Cervarix the vaccination incident should be reported to the GlaxoSmithKline registry (888-452-9622). Merck no longer maintains a registry for Gardasil (see next question). You should withhold further HPV vaccine until she is no longer pregnant. Shortly after the pregnancy is completed, administer HPV#2 assuming 1-2 months have passed since HPV#1. Give HPV#3 6 months after HPV#1, but no earlier than 12 weeks after HPV#2.
Why did Merck discontinue the registry for collecting reports of pregnant women who inadvertently received its HPV vaccine (Gardasil) during pregnancy?
Because HPV vaccine is not recommended for use during pregnancy, Merck facilitated a registry to document outcomes when its HPV vaccine (Gardasil) was inadvertently administered to pregnant women. This registry was ongoing for more than 6 years (June 2006 through April 2013), and Merck has fulfilled its FDA obligation to facilitate it. The data from the registry are reassuring with respect to safety after pregnancy exposures. Review of the data collected during the first 5 years of the registry does not support a causal relationship between HPV vaccine and birth defects.
Can HPV vaccine be administered at the same time as other vaccines?
Yes, coadministration of a different inactivated or live vaccine, either simultaneously or at any time before or after HPV vaccine, is permitted because neither HPV vaccine is a live vaccine.
If HPV vaccine is given subcutaneously (SC) instead of intramuscularly (IM), does the dose need to be repeated?
Yes. No data exist on the efficacy or safety of HPV vaccine given by the subcutaneous route. All data on efficacy and duration of protection are based on a 3-dose series given on the approved schedule and administered by the intramuscular route. In the absence of data on subcutaneous administration, CDC and the manufacturers recommend that a dose of HPV vaccine given by any route other than intramuscular should be repeated. There is no minimum interval between the invalid (subcutaneous) dose and the repeat dose.
If a 30-year-old female patient insists that she wants to be given HPV vaccine, can I give it to her?
HPV vaccine is not FDA-licensed for use in women older than age 26 years at this time. Studies are currently being conducted in women age 27 years and older. ACIP does not recommend the use of this vaccine outside the FDA licensing guidelines; however, many physicians administer this vaccine as off-label use. There is no reason to believe the vaccine would be any less safe for women in this age group than for younger women. Clinicians should decide if the benefit of the vaccine outweighs the hypothetical risk.
Contraindications and Precautions Back to top
If a woman has had HPV infection, can she still be vaccinated?
Yes. Women who have evidence of present or past HPV infection and who are younger than age 27 years should be vaccinated. They should be advised that the vaccine will not have a therapeutic effect on existing HPV infection or any cervical lesions.
Can a woman who is breastfeeding receive HPV vaccine?
Is the history of an abnormal pap a contraindication to the HPV vaccine series?
No. Even a woman found to be infected with a strain of HPV that is present in the vaccine could receive protection from the other 3 strains in the vaccine.
Vaccine Safety Back to top
We've heard stories in the media lately about severe reactions to the HPV vaccine. Is there any substance to these stories?
No. In summer 2008 some concerns were raised over two issues – reports of deaths and reports of Guillain-Barrè syndrome (GBS) following vaccination with Gardasil. As of September 2011, the manufacturer of Gardasil (Merck) reported it had distributed more than 40 million doses of Gardasil in the United States. At that time, the federal Vaccine Adverse Events Reporting System (VAERS) had received reports of 71 deaths, although only 34 could be confirmed. Among these 34 deaths, CDC reported that there was not a common pattern to the deaths; if there had been a common pattern, it would suggest the deaths might be caused by the vaccine.
Occurrences of GBS, a rare neurological disorder, have been reported through VAERS. FDA and CDC reviewed the reports and found no evidence that Gardasil increased the rate of GBS above what is expected in the population. CDC, working with the FDA and other immunization partners, will continue to monitor the safety of Gardasil and Cervarix vaccines. You can find complete information on this and other vaccine safety issues at www.cdc.gov/vaccinesafety/vaccines/HPV/gardasil.html.
This page was reviewed September 1, 2013
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This website is supported in part by a cooperative agreement from the National Center for Immunization and Respiratory Diseases (Grant No. 5U38IP000290) at the Centers for Disease Control and Prevention (CDC) in Atlanta, GA. The website content is the sole responsibility of IAC and does not necessarily represent the official views of CDC.