Introduction:
Human Papillomavirus (HPV) infections are a common sexually transmitted disease in men and women. They are associated with genital warts, cervical and penile carcinomas, and recurrent genital condyloma. Effective vaccines against HPV have been available for a decade, but widespread adoption is problematic for various reasons. However, the HPV vaccine Gardasil is safe and efficacious due to its novel nature and long-term efficiency.
What Is the HPV Vaccine?
HPV (Human Papillomavirus) vaccine refers to a vaccine that protects against HPV strains. HPV is a common sexually transmitted infection resulting in genital warts and certain cancers. The HPV vaccine is designed to prevent infection from high-risk virus strains that are responsible for causing HPV-related cancers. It is recommended for males and females and can be given at 11 and 45 years.
What Is the Mechanism of Action of the HPV Vaccine?
The HPV vaccines are composed of recombinant HPV proteins that form Virus-Like Particles (VLP) that neutralize antibodies against the viral effect of HPV genotypes found in the vaccine. HPV vaccine stimulates the body to produce antibodies that encounter HPV, bind to the virus, and prevent infection.
VLPs are safe as they do not have viral DNA (Deoxyribonucleic Acid) but are closely related to natural viruses, and antibodies against the VLPs also act against natural viruses. VLPs are highly immunogenic, inducing the antibody production that makes the vaccines effective. These vaccines do not prevent other sexually transmitted diseases or existing HPV infections.
Are HPV Vaccines Safe?
Yes, HPV vaccines have not shown any severe side effects after monitoring for more than 12 years. However, the common side effects, such as soreness at the injection site and other local symptoms similar to other vaccines, are noted.
The CDC (Centers for Disease Control and Prevention) and the FDA (Food and Drug Administration) conducted a safety review of side effects related to the Gardasil vaccine, which reported that the vaccine is safe for vaccine licensing to VAERS (Vaccine Adverse Event Reporting System). A few adverse events that the VAERS assessed are:
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Local injection site reactions.
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Syncope.
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Dizziness.
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Nausea.
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Headache.
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Hypersensitivity reactions such as anaphylaxis and rashes.
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Guillain-Barre Syndrome (a rare condition where the peripheral nerves are attacked by the person's immune system).
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Motor neuron disease (a condition that affects the nerves and brain).
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Autoimmune disorders (a condition in which the body's immune system attacks healthy body tissue).
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Transverse myelitis (inflammation of the spinal cord part).
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Pancreatitis (inflammation of the pancreas).
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Pregnancy and deaths.
These adverse reactions are mentioned on the label of the Gardasil vaccine. However, these events are not reported at rates more than expected in a population of a particular age group and sex and other known contributing factors.
The commonly reported adverse effects include:
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Syncope (fainting).
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Pain at the injection site.
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Nausea.
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Headache.
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Fever.
Based on the review, Gardasil is considered safe and effective as its benefits outweigh the risks.
Why Should We Get Vaccinated?
HPV vaccines are effective in protecting against HPV infections, cervical pre-cancers, cancers, genital warts, etc. The use of the HPV vaccine in the United States has been reported
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88% drop in HPV infections that cause cancer among girls and 81% among women.
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40% drop among vaccinated women prone to cervical cancers caused by HPV infection.
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HPV vaccines prevent cancer in women and men.
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HPV vaccines provide safe, effective, and long-term protection against HPV infection.
Are There Any Long-term Or Chronic Conditions Associated With The Vaccine?
Various clinical trials and studies were conducted to see if the HPV vaccine is associated with any chronic conditions, such as:
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Postural tachycardia syndrome.
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Guillain-Barre Syndrome.
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Premature ovarian failure.
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Complex regional pain syndrome.
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Chronic fatigue syndrome.
But, no evidence was found of an increase in these cases among HPV-vaccinated people. Furthermore, the WHO (World Health Organization) Global Advisory Committee On Vaccine Safety reviews emerging evidence on the safety of HPV vaccination. In March 2017, it issued a conclusion stating that there is no evidence to show an association between HPV vaccination and other chronic conditions.
Who Should Be Vaccinated?
The human papillomavirus (HPV) vaccination is given to:
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Children 12 to 13 years of age.
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Transgender people and MSM men (men who have sex with men) as they are at an increased risk of infection with HPV types 16 and 18, such as anal, penis, and oral cancers.
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Men with HIV-positive or immunocompromised conditions should take three doses of the HPV vaccine.
What Is Meant By The Safety Of The HPV Vaccine?
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Safety Of Vaccine:
Safety is defined by the presence of side effects followed by immunization in participants. A serious adverse effect is considered in case of death, life-threatening condition, hospitalization, chronic disability, or congenital abnormalities due to the vaccine. Clinical trials and studies were conducted in animals, males, females, and immunocompromised individuals to determine the safety and efficacy of the vaccine. These trials involve administering the vaccine to a group of people and monitoring them for any side effects. The Gardasil quadrivalent and nonavalent were used for the trials and studies.
Few showed good tolerance to the nonavalent vaccine. In addition, a randomized, double-blind study was conducted in 9 to 15-year-old girls divided into two groups, each receiving three vaccine doses. They reported at least one adverse reaction: nausea, fever, upper abdominal pain, headache, and fatigue. A study was conducted on homosexual and heterosexual men to understand the safety of vaccines compared to women. The most reported adverse effects include headache, pyrexia, and injection site reactions such as erythema, swelling, pain, and pruritis. Based on these findings, they concluded that the vaccine is well tolerated and no serious adverse effects were reported.
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Efficacy Of Vaccine:
The effectiveness and efficacy of the vaccine are remarkably high among young women. The efficacy of bivalent, quadrivalent, and nonavalent vaccines against HPV 16 and 18 showed similar effects. However, the nonavalent vaccine provides additional protection against HPV types 33,33,45,52,58. In addition, the nonavalent vaccine provides cross-protection along with bivalent and quadrivalent against HPV types 6,11,16,18,31,33,45,52,58. HPV vaccines are known to provide herd immunity as well. Although HPV vaccines are effective, screening for HPV-related cancers is recommended as per guidelines.
Who Should Not Get the HPV Vaccine?
HPV vaccine should be taken at the phase of pregnancy. If the person experiences any allergies after the first shot or is prone to life-threatening allergies, the HPV vaccine should not be taken. If the person is not feeling well, the HPV vaccine is not recommended until the person gets better.
When we have a closer look at the safety data of the HPV vaccine, the safety of this vaccine has been monitored by more than 160 studies, which have shown that the HPV vaccine has a better safety profile.
Conclusion:
Studies and clinical trials have shown that the vaccine is safe and efficacious. Few adverse effects are reported, including nausea, fever, abdominal pain, headache, and injection site reactions. CDC, WHO, and FDA regularly review and monitor for vaccine safety. There are no long-term effects associated with the immunization of the HPV vaccine. It also prevents HPV-related cervical and oropharyngeal, anal, vaginal vulvar, and penis cancers.
