Human Papillomavirus, commonly known as HPV, is a very common virus that can infect the skin and mucous membranes. There are over 100 different types of HPV, each identified by a specific number. HPV 33 is one such type. This virus is primarily transmitted through sexual contact, making it a sexually transmitted infection.
HPV 33 as a High-Risk Type
HPV types are broadly categorized into “low-risk” and “high-risk” classifications based on their potential to cause cellular changes. Low-risk types generally cause benign conditions like genital warts, which are non-cancerous growths. High-risk HPV types, including HPV 33, can cause abnormal cell changes that, if left unaddressed over many years, can progress to cancer.
These cellular changes do not automatically mean cancer will develop; the immune system often clears high-risk HPV infections on its own. However, persistent infections with high-risk types can lead to various cancers. These include cervical cancer, the most common HPV-related cancer, as well as anal, oropharyngeal (throat), vaginal, vulvar, and penile cancers. While HPV types 16 and 18 are responsible for the majority of HPV-related cancers globally, HPV 33 is also recognized as a high-risk type with oncogenic potential.
Transmission and Common Symptoms
HPV 33, like other types of HPV, is transmitted through direct skin-to-skin contact, most often during sexual activity. This includes vaginal, anal, and oral sex. The virus can be passed even when there are no visible warts or symptoms present.
HPV infections, including type 33, are often asymptomatic. Individuals can carry the virus for years without experiencing any noticeable symptoms. This means a person may be unaware they have the infection.
Screening and Diagnosis
Healthcare providers detect HPV 33 primarily through specific screening tests. For individuals with a cervix, the Pap test, also known as a Pap smear, is a common screening tool that looks for abnormal cells on the cervix that could be caused by HPV. A separate test, the HPV test, directly detects the genetic material, or DNA, of high-risk HPV types.
When a high-risk HPV type is identified, laboratories can perform HPV genotyping. This process identifies the specific strain of the virus. A positive result for high-risk HPV, particularly HPV 33, often leads to a recommendation for a colposcopy. This procedure involves a magnified examination of the cervix to allow the healthcare provider to closely inspect any areas of concern and take biopsies if necessary.
Prevention and Medical Follow-Up
Prevention of HPV 33 and other high-risk types is primarily achieved through vaccination. The HPV vaccine, such as Gardasil 9, protects against HPV 33 along with several other major high-risk types and some low-risk types. Administering the vaccine before an individual becomes sexually active offers the most effective protection by preventing initial exposure to the virus.
While condoms can reduce the risk of HPV transmission, they do not offer complete protection because the virus can be present on skin areas not covered by a condom. Following a positive HPV 33 diagnosis, management often involves “watchful waiting” and more frequent screening. This approach allows the immune system time to clear the virus, as many infections resolve naturally. If abnormal cells persist or worsen, procedures such as Loop Electrosurgical Excision Procedure (LEEP) or cryotherapy may be performed to remove the affected tissue. These interventions aim to prevent the progression of cellular changes to cancer.