Human papillomavirus (HPV)

What

There are several types of human papillomavirus (HPV) that infect cutaneous and mucosal epithelial tissues. Most people clear HPV infections, but the virus persists in some cases.

Who

9vHPV (9-valent HPV) vaccine is recommended for:

• adolescents and young adults aged 9–25 years
• people with severely immunocompromising conditions
• men who have sex with men

How

The recommended schedule for adolescents and young adults aged 9–25 years, who are immunocompetent, is 1 dose.

The recommended schedule for people aged ≥26 years is 3 doses, with an interval of 2 months between dose 1 and dose 2, and 4 months between dose 2 and dose 3.

The recommended schedule for people with severely immunocompromising conditions, regardless of age, is 3 doses, with an interval of 2 months between dose 1 and dose 2, and 4 months between dose 2 and dose 3.

Why

Up to 90% of the general population will be infected with at least 1 genital type of HPV at some time in their lives. People with persistent HPV infection are at risk of developing HPV-associated cancers; the most common is cervical cancer.

Human papillomavirus vaccines available in Australia

The Therapeutic Goods Administration website provides product information for each vaccine.

See also Vaccine information and Variations from product information for more details.

Dose and route

The dose of all HPV vaccines is 0.5 mL given by intramuscular injection.

A single dose

A single dose is recommended for immunocompetent people who start the HPV vaccination course at 9–25 years of age (that is, before their 26th birthday).

People who receive their 1st HPV vaccine dose at ≥26 years of age (that is, on or after their 26th birthday) are recommended to receive 3 doses, with an interval of 2 months between dose 1 and dose 2, and 4 months between dose 2 and dose 3.

See Table. Recommended doses and intervals between doses for human papillomavirus (HPV) vaccines, by age group at the start of the course.

If the person has received doses with shorter intervals, see Table. Catch-up schedule for people ≥10 years of age (for vaccines recommended on a population level). The person may need extra doses.

Although there is no specified upper limit for the interval before the final dose in the 3-dose schedule, it is advisable to complete the schedule as soon as possible, as per the recommended schedule, to ensure adequate protection is achieved in a timely manner. Doses do not need to be repeated if the recommended interval between doses is exceeded.

Additional doses of 9vHPV vaccine

People who have completed the recommended number of doses of 2vHPV (2-valent HPV) or 4vHPV (4-valent HPV) vaccine are not routinely recommended to receive 9vHPV vaccine, because the extra benefit is considered to be marginal.

However, if the person wants protection against the additional HPV types, there appears to be no safety concerns associated with giving 9vHPV vaccine after a completed 2vHPV or 4vHPV vaccine course. ¹²

Co-administration with other vaccines

HPV vaccines can be given at the same time as the following vaccines, using separate syringes and injection sites:^13-19

• dTpa (reduced antigen content diphtheria-tetanus-acellular pertussis vaccine)
• dTpa-IPV (reduced antigen content diphtheria-tetanus-acellular pertussis, inactivated poliovirus vaccine)
• hepB (monovalent hepatitis B vaccine)
• MenACWY (quadrivalent meningococcal conjugate vaccine)
• COVID-19 vaccines (if required)

Interchangeability of HPV vaccines

If a multi-dose schedule is required, 9vHPV vaccine can be used to complete an HPV vaccination schedule that was started with either the 4vHPV or the 2vHPV vaccine, as long as the appropriate minimum intervals and dose numbers are used.

The only absolute contraindications to HPV vaccines are:

• anaphylaxis after a previous dose of any HPV vaccine
• anaphylaxis after any component of an HPV vaccine
• anaphylaxis to yeast (for 9vHPV)

Women who are pregnant or breastfeeding

HPV vaccines are not recommended for pregnant women, due to an absence of evidence of vaccine use in large populations of pregnant women.

Women who become pregnant after starting the HPV vaccination course and require more than one dose are recommended to stop the vaccination course and receive the remaining doses after pregnancy.

Women who are inadvertently given a dose of HPV vaccine around the time of conception or during pregnancy should be reassured that there is evidence suggesting that vaccination does not harm the mother or the fetus in these situations.

In the 9vHPV vaccine clinical trials, some women became pregnant during the trial, despite recommendations for participants to avoid pregnancy. The overall proportions of pregnancies that resulted in an adverse outcome (spontaneous abortion, late fetal death, infant with congenital anomalies) were similar among 9vHPV vaccine recipients and placebo or control vaccine recipients.²⁰ In addition, pooled analyses of women who became pregnant during clinical trials of 2vHPV and 4vHPV vaccines showed that, overall, there were no differences in pregnancy outcomes between HPV vaccine recipients and control vaccine recipients.^21-23

Breastfeeding women can receive HPV vaccines.²⁴

See Table. Vaccines that are not recommended in pregnancy in Vaccination for women who are planning pregnancy, pregnant or breastfeeding for more details.

HPV vaccination is generally safe and well tolerated. The safety profile and the spectrum of adverse events after vaccination in males are similar to those in females.^25,26

For all HPV vaccines, injection site reactions are the most commonly reported adverse event, and occur in 80–90% of vaccine recipients.^20,27,28   These reactions are less frequent in younger girls and boys than in adult women.²⁷

In most clinical trials, rates of systemic adverse events were comparable between HPV vaccine recipients and control vaccine recipients, and included:^28,29

• headache
• fever
• nausea
• dizziness
• fatigue

Meta-analyses on both the 2vHPV and 9vHPV vaccines show no increase in the number of serious adverse events in vaccine recipients compared with control recipients.^20,30  A safety review of 7 phase III clinical trials with 9vHPV vaccine reported serious adverse reactions in <0.1% of the more than 15,000 participants.²⁰  Australian data show that rates of anaphylaxis following HPV vaccines are low (0.32 per 100,000) and consistent with rates for other vaccines.^27,31,32

Syncope in adolescents

Post-marketing passive surveillance of HPV vaccine use has identified syncope (fainting) as a common adverse event immediately after HPV vaccination in adolescents.^32-35 It was more commonly reported when HPV vaccine was first introduced in Australia (reported at a rate of 29.6 per 100,000 doses), but is now more rare (7.1 per 100,000 doses).³⁶

Syncope is a benign and manageable risk of adolescent vaccination. It is likely to be a reaction to the process of vaccination, rather than to the vaccine itself. Immunisation providers should ensure that procedures are in place to minimise the risk of syncope-related falls around the time of vaccination.

See also Adverse events following immunisation.

Guillain–Barré syndrome

A 2015 French study in more than 2 million girls suggested a possible very small risk (approximately 1 in 100,000 girls vaccinated) of Guillain–Barré syndrome (GBS). However, a relationship between HPV vaccination and GBS has not been observed in any other well-conducted studies.³⁷ Large studies collectively including more than 10 million vaccine recipients have shown that GBS is very rare and the evidence for an association with HPV vaccination is weak.^38-41 Ongoing research is monitoring whether there is any increased risk of GBS after HPV vaccination.

Other adverse events

There is no consistent evidence to suggest that HPV vaccination can cause the following events:^27,32

• new-onset autoimmune disease
• primary ovarian insufficiency
• complex regional pain syndrome
• postural orthostatic tachycardia

The World Health Organization’s Global Advisory Committee on Vaccine Safety,⁴² the European Medicines Agency,⁴³ the Australian Therapeutic Goods Administration and various other key global expert vaccine groups have reviewed the evidence for a causal association between HPV vaccine and a number of these reported adverse events. These extensive reviews have not found any safety issue that would change positive recommendations for the use of the vaccine. The reviews have concluded that HPV vaccines are extremely safe.³⁷

Human papillomaviruses are small, non-enveloped viruses with circular double-stranded DNA. They infect and replicate primarily within cutaneous and mucosal epithelial tissues.

More than 100 HPV genotypes have been fully sequenced. The genotypes are differentiated by sequence variations in the major genes. HPV genotypes differ in their preferred site of infection. Approximately 40 HPV types specifically infect the anogenital tract.⁴⁴

Pathogenesis

HPV requires a breach in the epithelial surface to enter the basal epithelial cells and cause infection. However, infectious virions are only produced in the terminally differentiated layer of the epithelium.⁴⁵

HPV types 16, 18, 31, 33, 35, 45, 52 and 58 are high risk because they can cause cancer. The most oncogenic HPV type is HPV-16. This is the most frequent cause of HPV-related cancers. See Clinical features.⁴⁶

HPV types 6, 11, 40, 42, 43, 44, 54, 61, 70, 72, 81 and 89 are low risk. These are mostly associated with non-malignant lesions such as genital warts. Other HPV types are uncommon, and their associations with disease are undetermined. However, they are not currently believed to be significant causes of cancer.^47,48

Transmission

Anogenital HPV is mainly transmitted through sex. Less commonly, the virus can be transmitted after intimate non-penetrative sexual contact.⁴⁹

Perinatal transmission of HPV can result in laryngeal infection in infants. In rare cases, this can lead to recurrent respiratory papillomatosis.⁵⁰

HPV infection is often subclinical, but can cause a range of lesions depending on the infecting HPV genotype.

Low-risk HPV types

Low-risk HPV types may cause lesions such as:

• cutaneous warts
• genital warts
• respiratory papillomatosis

Anogenital warts may present as painless lumps, or with local tenderness, itching or bleeding.

Recurrent respiratory papillomatosis is potentially fatal. It is characterised by multiple warty growths on the mucosal surface of the respiratory tract.⁵¹

Most people clear genital HPV infections (that is, the infection is no longer detectable by HPV DNA testing) within 12–24 months. However, in some cases, the virus is thought to remain as a latent infection even though DNA is no longer detectable.

In about 3–10% of infections, the virus persists. People with persistent HPV infection are at risk of developing HPV-associated cancers.^52-54

High-risk HPV types

High-risk HPV types may cause dysplasias and cancers of the:

• cervix
• vulva
• vagina
• penis
• anus
• oral cavity
• oropharynx

Dysplasias may be:

• low grade — the viral cytopathic effect of HPV infection
• high grade — precursors to cancer

Cervical cancer

The causal link between persistent cervical HPV infection and cervical cancer is well established.⁵⁵

Cellular changes in the cervix as a result of HPV infection are referred to as cervical intraepithelial neoplasia. Most of these changes regress, but some will progress to cervical cancer.

Malignant transformation in the cervix usually occurs 10–20 years after infection with high-risk HPV types, but has been reported within 2 years.⁵⁶

Other cancers

The strength of association between HPV infection and cancers other than cervical cancer varies by site and HPV type.⁵⁵

The clinical features of HPV-associated cancers and their precursor lesions depend on the anatomical site. Clinical features also vary within the oropharynx and anogenital sites other than the cervix. The progression of HPV-associated precursor lesions to cancers is less well understood in non-cervical sites than in the cervix.

Infection with HPV is very common in both men and women. Initial infection occurs close to the time of sexual debut. Up to 90% of the general population will be infected with at least 1 genital type of HPV at some time in their lives.⁵⁷

The median age of sexual debut for both males and females in Australia was 17 years in 2012–13.⁵⁸ In 2008, a national survey found that about 80% of senior secondary school children aged approximately 15–19 years engaged in some form of sexual activity that may transmit HPV.⁵⁹

HPV infection rates differ between geographic regions. Estimated population prevalence of HPV also varies depending on the anatomical site and the lesions sampled.

Prior to the HPV vaccination program, about two-thirds of Australian women aged 15–20 years participating in cervical screening had HPV DNA detected in cervical samples collected for cytology.⁶⁰

Less than 60% of women with HPV infection develop antibodies. The proportion is even lower in men.^61-63 In a 2005 Australian serosurvey, 24% of females and 18% of males aged 0–69 years were seropositive to at least 1 of the 4 HPV types 6, 11, 16 and 18.⁶⁴ Females became seropositive to HPV at 10–14 years of age and males at 15–19 years of age.

Risk groups

Certain population subgroups are at increased risk of HPV infection and HPV-associated diseases than the general population, including:

• men who have sex with men (MSM)
• people who are immunocompromised (as a result of disease or medical treatment).⁶⁵

MSM are more commonly infected with multiple HPV genotypes and take longer to clear infection.^6,66,67 Studies of MSM of varying ages in Victoria have shown that HPV infection was detected in three-quarters of men tested.^68,69 Meta-analyses of data worldwide show that vaccine-type HPV infections are more prevalent in MSM (70.5% and 42.6% in those with and without HIV, respectively) compared with heterosexual men (22.2% and 5.4% in those with and without HIV, respectively).⁹

HPV infection and associated disease is more common in people living with HIV. HPV infection, especially of vaccine-types, is most common in MSM who are also HIV-positive.⁹ The prevalence of anal lesions is higher in MSM with HIV (22.4%) compared with MSM without HIV (11.3%). Even among heterosexual men, vaccine-type HPV infections were more frequent among HIV-positive men (22.2%) compared with HIV-negative men (5.4%).⁹ The risk of HPV infection and cervical cancer is also higher in women with HIV.⁷⁰

Diseases attributed to HPV infection

Cervical cancer

Worldwide, approximately 70% of cervical cancers contain HPV-16 or HPV-18 DNA.⁷¹

Prevalence of HPV-16 and HPV-18 in Australia

Australian data collected between 2005 and 2015 indicate that HPV-16 and HPV-18 are detected in approximately 77% of all cervical cancers. It is estimated that an extra 15.9% of cervical cancers are attributable to HPV types 31, 33, 45, 52 and 58.^72-74

In Australia, cervical cancer ranked 23rd of cancers contributing to the overall cancer disease burden in 2011. Cervical cancer occurs predominantly in women who are unscreened or underscreened through the National Cervical Screening Program.⁷⁵

Incidence and prevalence of cervical cancer

In 2018, the age-standardised incidence rate of cervical cancer in Australia was 7.3 per 100,000. The mortality rate was 1.6 deaths per 100,000 women.⁷⁶

The prevalence of high-risk HPV types 16 and 18, detected when cervical samples collected for cytology were tested for HPV DNA, was similar in Aboriginal and Torres Strait Islander women and non-Indigenous women.⁶⁰

However, the incidence rate of cervical cancer in Aboriginal and Torres Strait Islander women is more than twice that in non-Indigenous Australian women. Between 2012 and 2016, cervical cancer incidence (age-adjusted) was 20.3 per 100,000 in Aboriginal and Torres Strait Island women compared with 10.0 per 100,000 in non-Indigenous women.⁷⁶ This indicates that fewer Aboriginal and Torres Strait Islander women participate in cervical screening programs. It also suggests a greater prevalence of cofactors for cervical cancer, such as:^77,78

• smoking
• earlier and more pregnancies
• lower socioeconomic status

Aboriginal and Torres Strait Islander women are 4 times more likely to die from cervical cancer than non-Indigenous women.⁷⁹

Australian women in remote and very remote areas have 1.5 times higher cervical cancer incidence than those living in major cities.⁷⁹

Surveillance data and research studies have shown a positive impact of the HPV vaccination program on cervical HPV prevalence and cervical intraepithelial neoplasia.⁸⁰ Cervical screening data show that the prevalence of HPV-16 and HPV-18 in 2017–2018 was low (2.1%) and stable across all age groups, contrasting with rate before the vaccination program when rates were substantially higher in young women especially those aged younger than 25 years.⁸¹ Declines in vaccine-type HPV infection have been recorded among Aboriginal and Torres Strait Islander women, with one study reporting a decline in 4vHPV-types from 23.9% to 1.4%.⁸² Victorian and national cervical screening data demonstrate a decline in high-grade lesions in women aged up to 30 years.^77,83

Australia has committed to eliminating cervical cancer by 2035.⁸⁴ Modelling studies have shown that if high vaccine coverage and screening is maintained, cervical cancer could be eliminated (<4 new cases per 100 000 women annually) as a public health problem in Australia by 2028.⁸⁵ However, due to higher disease incidence and inequities in access to cervical screening and treatment, elimination will likely be delayed for Aboriginal and Torres Strait Islander women.^85,86

Other anogenital cancers

Proportion attributed to HPV

The proportion of cancers of anogenital sites other than the cervix that are attributable to HPV ranges from approximately 40% for vulval cancers to approximately 90% for anal cancers.⁸⁰

Of these HPV-associated cancers:

• more than 85% have evidence of infection with the high-risk HPV types 16 and 18⁸⁰
• about 11–18% in women and 4–9% in men are attributable to HPV types 31, 33, 45, 52 and 58⁸⁰

Incidence of anogenital cancers

In Australia in 2018, the age-standardised incidence of:⁷⁶

• vulval cancer was 2.3 per 100,000 (n = 348)
• vaginal cancer was 0.6 per 100,000 (n = 99)
• penile cancer was 1.1 per 100,000 (n = 159)
• anal cancer was 2.1 per 100,000 in women and 1.4 per 100,000 in men

MSM have a significantly higher incidence of high-grade anal intraepithelial neoplasia and anal cancer than the general population. Overseas studies have found a greater than 30-fold higher incidence of anal cancer in MSM than in other men.^8,87

Overall, anal cancer incidence has been steadily increasing during the past few decades. The increase has been greater in males than in females.^88,89

Oropharyngeal cancers

The proportion of oropharyngeal cancers that are associated with HPV varies widely, from 12% to 63%. The proportion of oral cancers associated with HPV is lower.⁸⁰ HPV-16 and HPV-18 account for more than 95% of HPV-positive cancers at these sites.⁸⁰

Many western countries, including Australia and the United States, have seen a steady increase in the burden of HPV-positive oropharyngeal cancers during the past few decades.^88,90-94 These cancers are mainly attributable to cancers of the base of the tongue and tonsils.

HPV-associated lesions

Prior to the HPV vaccination program, the population incidence of benign HPV-associated lesions, such as anogenital warts, was much higher than the incidence of HPV-associated cancers.

HPV types 6 and 11 are associated with 90% of genital warts.^95-97

A study including 34 sexual health centres showed a 72% decrease in the proportion of all Australian-born first-time clinic attendees diagnosed with genital warts between 2004 and 2018.⁹⁸ This decline was greatest in Australian-born men and women aged younger than 21 years (98%). Vaccinating females also provides some herd protection to males — studies have shown a significant decline in the diagnosis of genital warts in unvaccinated males of the same age.^99-101

Respiratory papillomatosis

Recurrent respiratory papillomatosis is a rare disease (prevalence approximately 3.5 per 100,000) that occurs in both childhood and adult forms. It is associated with HPV types 6 and 11 in 100% of cases.^96,102-104 In Australia, the average annual incidence of JORRP declined from 0.16 per 100,000 in 2012 to 0.02 per 100,000 in 2016.¹⁰⁵

2 HPV vaccines are available for use in Australia:

• 2vHPV (Cervarix), which contains virus-like particles of HPV types 16 and 18
• 9vHPV (Gardasil 9), which contains virus-like particles of HPV types 6, 11, 16, 18, 31, 33, 45, 52 and 58

Virus-like particles are not infectious, and do not replicate or cause cellular abnormalities.^106,107

Australia’s National Immunisation Program uses 9vHPV vaccine.

Vaccine efficacy in females 16–26 years of age

Efficacy of the 2vHPV, 4vHPV and 9vHPV vaccines has been assessed in females in several international clinical trials.

2vHPV and 4vHPV vaccines

In women aged approximately 16–26 years who are naive to HPV types 16 and 18 before vaccination, the 2vHPV and 4vHPV vaccines (in a 3-dose schedule) are both about 90–100% effective at preventing type-specific persistent infection and related cervical disease.

The 4vHPV vaccine is 100% effective (95% CI: 94–100%) against vaginal and external anogenital lesions associated with HPV types 6, 11, 16 and 18 in women.^108-113

These include:

• genital warts
• vulval dysplasia
• vaginal dysplasia
• perineal dysplasia
• perianal dysplasia

The 2vHPV vaccine also provides considerable cross-protection against cervical infection with HPV types 31, 33 and 45.¹¹⁴

9vHPV vaccine

The 9vHPV vaccine has established efficacy (97.4%; 95% CI: 85.0–99.9%) against the following neoplasias and cancers that are associated with HPV types 31, 33, 45, 52 and 58:¹¹⁵

• cervical
• vulval
• vaginal

A clinical trial of 9vHPV vaccine in women aged 16–26 years established non-inferiority of the 9vHPV vaccine against the 4vHPV types (6, 11, 16 and 18). Incidence of disease endpoints was similarly low in women vaccinated with either 9vHPV or 4vHPV vaccine.¹¹⁵

Vaccine efficacy in males 16–26 years of age

1 clinical trial has shown the efficacy of 4vHPV vaccine in males aged 16–26 years.¹¹⁶

Vaccination was 84–100% protective against persistent anogenital infection and external genital lesions due to vaccine HPV types among HPV-naive participants.

Among HPV-naive participants in the trial, vaccine efficacy in men who have sex with men was:

• 95% against intra-anal HPV infection
• 75% against high-grade anal intraepithelial neoplasia

Efficacy of 2vHPV and 9vHPV vaccines in males has not been assessed to date. However, these vaccines have demonstrated safety and immunogenicity in adolescent and adult males.^25,26,117

Vaccine efficacy of 1 dose of HPV vaccine

Studies of 1 dose of 4vHPV and 2vHPV vaccines show that a single dose given to girls and women aged 9 to 25 years provides protection against HPV infection that is comparable to 2 or 3 doses of vaccine, and persists over several years.^3,4,118,119

A clinical trial showed that the efficacy of 1 dose of 9vHPV vaccine against persistent HPV infection was 97.5% in young women aged 15 to 20 years.¹

A clinical trial showed that an effective immune response occurs in almost all vaccine recipients of a single dose of 9vHPV or 2vHPV vaccine (>99% for HPV16 and >98% for HPV18).² Although the antibody titres induced by a single dose of vaccine are lower compared to those after 2 or 3 doses, they stabilise from 12 months onwards.² Long-term studies of 4vHPV and 2vHPV vaccines have shown that the immune response remains stable from 12 months up to 11 years after vaccination, during which time protection against HPV infection is maintained.^4,120-122

The effectiveness or efficacy of a single dose of HPV vaccine has not yet been studied in males. However, the immune response and clinical protection afforded by the vaccine is expected to be similar in males and females.

Vaccine efficacy in people already infected with HPV

In women who are vaccinated regardless of their baseline HPV status (that is, women who may have pre-existing HPV infection), vaccine efficacy is lower than in HPV-naive women. This suggests reduced vaccine effectiveness among females who are already sexually active. This is because the HPV vaccines are prophylactic vaccines — they prevent primary HPV infection.

Vaccination does not:

• treat an existing HPV infection
• prevent disease that may be caused by an existing vaccine HPV-type infection^29,123-125

HPV vaccine protection is believed to be predominantly antibody mediated. Even low levels of antibodies can stop HPV entering the basal epithelial cells. HPV can only access the basal cell at sites of microtrauma, where there is a breach in the epithelium, and circulating HPV antibodies from sera are present at these sites.⁴⁵

Because antibodies prevent viral entry, vaccination may still benefit sexually active men and women by protecting them against:

• new infections with other vaccine-preventable HPV types
• reinfection with vaccine-preventable types they have previously been exposed to — for example, from an infected partner
• auto-inoculation of existing persistent HPV infection to other sites

Immunogenicity in females and males <16 years of age

Pre-market trials did not assess the efficacy of HPV vaccines in females or males <16 years of age because these studies need genital samples. The trials used immunobridging studies to ensure that antibody responses in the target age of young adolescents were equivalent to those known to be protective in older women.

Young adolescents had higher antibody titres than older women.¹²⁶ Later studies confirmed that a widely spaced 2-dose HPV vaccine schedule for those aged 9–14 years at the time of the 1st dose also produced non-inferior antibody titres.¹²⁷

For the 2vHPV and 9vHPV vaccines, antibody responses in pre-adolescent and adolescent females and males (>9 years of age) after 2 vaccine doses were equivalent to those in adult women, in whom clinical efficacy has been demonstrated.^126,128

A clinical trial showed that an effective immune response occurs in almost all girls aged 9–14 years who received a single dose of 9vHPV or 2vHPV vaccine (>99% for HPV16 and >98% for HPV18).² Immunogenicity in this study population was non-inferior to adolescents aged 9–19 years in whom vaccine effectiveness had previously been demonstrated following a single dose of 2vHPV or 4vHPV vaccine.¹²⁹

Duration of immunity

It is currently unknown if immunity following HPV vaccination is lifelong. However, current data support a persistent, stable antibody level after an initial plateau over many years. Long-term population-based follow-up studies to assess this are underway. In clinical trials in women,¹¹⁵ vaccine efficacy for multi-dose schedules is up to:

• 6 years for 9vHPV vaccine
• 10 years for 2vHPV vaccine

Observational studies demonstrate that a single dose of HPV vaccine provides protection up to 11 years after vaccination.^3,4 Immunogenicity stabilises 12 months after vaccination, and does not appear to wane thereafter.

A clinical trial of 9vHPV vaccine in girls aged 9–14 years showed that immune responses after a single dose of 9vHPV or 2vHPV vaccine last up to 36 months after vaccination.^2,130

Duration of protection has only been demonstrated against HPV types 6, 11, 16 and 18. However the duration of protection is expected to be similar for HPV types 31, 33, 45, 52 and 58.

Transport according to National Vaccine Storage Guidelines: Strive for 5.¹³¹ Store at +2°C to +8°C. Do not freeze. Protect from light.

Not applicable.

Indicated ages for vaccination

The product information for the 9vHPV vaccine, Gardasil 9, states that this vaccine is indicated for:

• males and females up to 45 years of age

The Australian Technical Advisory Group on Immunisation (ATAGI) recommends that the following groups can also receive 9vHPV vaccine:

• MSM of any age
• people of any age who are immunocompromised

ATAGI also recommends that males and females older than the upper indicated ages can receive 9vHPV vaccine if they are at risk of future HPV exposure and disease.

Dose schedule

The product information of the 9vHPV vaccine, Gardasil 9, states that this vaccine should be given:

• in a 2-dose schedule to people aged 9–14 years
• in a 3-dose schedule to people aged ≥15 years

The Australian Technical Advisory Group on Immunisation (ATAGI) recommends the following dose schedule:

• 1 dose for immunocompetent people aged 9–25 years
• 3 doses for immunocompetent people aged ≥26 years

See Table. Recommended doses and intervals between doses for human papillomavirus (HPV) vaccines, by age group at the start of the course for the appropriate dosing intervals.

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