Human papillomaviruses (HPV) are a very common family of viruses that infect epithelial tissue of males and females. More than 150 HPV types have been identified. Most HPV types cause common warts on the hands and feet. Approximately 40 HPV types can infect cells on the genitals, mouth and throat. Most of these HPV infections are asymptomatic and resolve spontaneously. Some HPV infections can persist and lead to health problems such as genital warts, and cancers such as cervical, vaginal and vulvar cancers in women, penile caners in men and oropharyngeal and anal cancers in both men and women. High-risk types HPV 16 and 18 account for 80% of cancers caused by HPV. Infection with low-risk HPV types such as HPV 6 and 11 can cause genital warts, laryngeal papillomas or cervical cell abnormalities.
You can get HPV by having vaginal, anal or oral sex with someone who has the virus. HPV can be passed even when an infected person has no signs or symptoms. In other words, anyone who is sexually active can get HPV, even if you have had sex with only one person. You can develop symptoms years after you have sex with someone who is infected. This makes it hard to known when you first became infected.
There is no test to find out a person’s “HPV status”. Most people with HPV do not know they are infected and never develop symptoms or health problems from it. Some people find out they have HPV when they get genital warts or an abnormal Pap test result. Others may only find out once they have cancers.
There are HPV tests that can be used to screen for cervical cancer. These tests are only recommended for screening in women aged 30 years or older, but not in men, adolescents or women under the age of 30 years. Also, there is no approved HPV test to find HPV in the mouth or throat.
HPV vaccine can be started as early as 9 years old. For people who did not have vaccination when they were younger, vaccination is also recommended for males aged 13 to 21, females aged 13 to 26. Women who have had an unclear or abnormal Pap test, a positive HPV test, or genital warts may receive the vaccine but the vaccine may not have any therapeutic effect. For people who are immune-compromised, the immune response to vaccination and effectiveness of the vaccine might be less than in people with a normally functioning immune system. HVP vaccine is also recommended for gay and bisexual men and breastfeeding women.
If you are about to take Gardasil-9 vaccine, please check if you have any of the following conditions. If so, you are not suitable to get vaccinated:
Allergic to any component of this vaccine including yeast;
Patients with moderate or severe acute illnesses;
Very common and common reactions after Gardasil-9 (1/10 to 1/100)Redness, swelling and pain at the injection site;
Pain in the arms, hands, fingers, legs, feet or toes;
Dizziness and fainting. You should be seated or lying down during vaccination and remain in that position for 15 minutes after the vaccine is given.
Rare reactions (1/1000 – 1/10000) and very rare reaction (<1/10000) have also been reported. These include itchy red rash (hives), difficulty in breathing, restriction of the airways, fits (convulsions) and anaphylactic reaction.
If the first dose of Gardasil-9 is given before the 15th birthday, the second dose is recommended 6-12 months later (0, 6-12 month schedule). The minimum interval is 5 months, otherwise a third dose will be needed 6-12 months after the first dose and a minimum of 12 weeks after the second dose.
If the first dose is given on or after the 15th birthday, vaccination should be completed according to a 3-dose schedule. The second dose is recommended 1-2 months later, and the third dose is recommended 6 months after the first dose (0, 1-2, 6 month schedule). The minimum intervals are 4 weeks between the first and second dose, 12 weeks between the second and third dose.