The HPV Vaccine: Who Needs It, When and Why? An Evidence-Based Guide

The Human Papillomavirus (HPV) is the most common sexually transmitted infection worldwide. More than 80% of sexually active women and men will encounter HPV at some point in their lives. With over 200 subtypes, the virus is the leading cause of cervical cancer and is also responsible for a range of other cancers and genital warts. The HPV vaccine is one of the most effective preventive tools in modern medicine, making the majority of these diseases preventable.

What is HPV and what does it do?

HPV is a DNA virus that infects skin and mucosal cells. Around 90% of infections are cleared by the immune system within two years. However, persistent infection with high-risk types — particularly HPV 16 and 18 — can lead to cellular changes (dysplasia) and, over time, to cancer. Low-risk types (HPV 6 and 11) cause genital warts.

Which cancers does HPV cause?

• Cervical cancer: Approximately 99% of cases are HPV-related; it is the fourth most common cancer in women globally.
• Vulvar and vaginal cancers: Around 70% of cases are HPV-related.
• Anal cancer: Around 90% of cases in both men and women are caused by HPV.
• Penile cancer: Around 60% of cases are linked to HPV.
• Oropharyngeal (head and neck) cancers: HPV is detected in approximately 70% of tonsil and base-of-tongue cancers, with rising incidence in men.
• Genital warts (condylomata): Over 90% of cases are caused by HPV types 6 and 11.

Types of HPV vaccine

The current standard vaccine used worldwide is Gardasil 9, which protects against nine HPV types: 6, 11, 16, 18, 31, 33, 45, 52 and 58. Together these account for approximately 90% of cervical cancer cases and more than 90% of genital warts.

Who should be vaccinated?

1. Ages 9–14: the ideal window

The vaccine is most effective when administered before sexual activity begins. Immune response is strongest in this age group and only 2 doses (0 and 6–12 months) are required. Current WHO evidence suggests a single-dose schedule may also provide adequate protection in this age band.

2. Ages 15–26: routine recommendation

The vaccine is recommended even after sexual activity has started. A 3-dose schedule (0, 2 and 6 months) is used. Prior exposure to one or two HPV types does not eliminate the benefit — the vaccine still protects against the remaining types.

3. Ages 27–45: an individual decision

In 2018, the FDA extended vaccine approval up to age 45. In situations such as a new partner, a change in relationship status, or a normal HPV-negative smear, the vaccine may be offered after a shared risk–benefit discussion with your clinician.

4. HPV vaccination for men

HPV is not a women's disease alone. Vaccination protects men against anal, penile and oropharyngeal cancers, and reduces the risk of transmitting the virus to their partners. Vaccination is recommended for boys and young men between the ages of 9 and 26.

Dosing schedule at a glance

• Ages 9–14: 2 doses — 0 and 6–12 months
• Age 15 and above: 3 doses — 0, 2 and 6 months
• Immunocompromised individuals (HIV, transplant recipients, etc.): 3 doses regardless of age

Is the vaccine safe? Side effects

The HPV vaccine has been in use in over 100 countries since 2006 and is endorsed as safe by the WHO, FDA and EMA. The most common side effects are:

• Pain, redness or swelling at the injection site (approx. 80%)
• Mild fever and headache (10–15%)
• Transient fatigue
• Nausea (rare)

Vasovagal (fainting) reactions can occasionally occur within the first 15 minutes, particularly in adolescents, so a 15-minute observation period after vaccination is recommended. The vaccine has no established link with infertility, autoimmune disease or cancer; such claims have been refuted by extensive scientific studies.

Pregnancy and breastfeeding

The HPV vaccine is not recommended during pregnancy; the schedule is postponed until after delivery. Inadvertent administration during pregnancy is not an indication for termination. The vaccine is considered safe during breastfeeding.

Do vaccinated women still need cervical screening?

Yes. Gardasil 9 protects against nine HPV types but does not cover every oncogenic type (approximately 10% of cervical cancers are caused by other types). Regular cervical screening with Pap smear and HPV DNA testing should therefore continue from age 21–25 onwards, even in vaccinated women.

Frequently asked practical questions

• Does the vaccine treat existing HPV? No. The vaccine is preventive, not therapeutic.
• Are there sexual-activity restrictions after vaccination? No restrictions are required.
• Can postmenopausal women be vaccinated? Routine vaccination is not recommended above 45, but may be considered in selected cases after clinician review.
• Is the vaccine free? Availability and cost vary by country. In many nations, the vaccine is offered free of charge to adolescents aged 9–14 as part of national immunisation programmes.

HPV vaccination and counselling in Adana

The HPV vaccine is one of the most valuable investments you can make in the long-term gynaecologic health of yourself, your daughter or your son. Op. Dr. Sadık Kükrer offers individualised consultation in Adana on HPV vaccination, Pap smear and HPV DNA screening, and the treatment of cervical dysplasia (colposcopy, LEEP/conisation). International patients are welcome to arrange an appointment for age-appropriate vaccination decisions, dosing schedules or interpretation of HPV test results.