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89-540: Human papillomavirus infection ( HPV infection ) is caused by a DNA virus from the Papillomaviridae family. Many HPV infections cause no symptoms and 90% resolve spontaneously within two years. In some cases, an HPV infection persists and results in either warts or precancerous lesions . These lesions, depending on the site affected, increase the risk of cancer of the cervix , vulva , vagina , penis , anus , mouth, tonsils, or throat . Nearly all cervical cancer

178-454: A genome made of deoxyribonucleic acid (DNA) that is replicated by a DNA polymerase . They can be divided between those that have two strands of DNA in their genome, called double-stranded DNA (dsDNA) viruses, and those that have one strand of DNA in their genome, called single-stranded DNA (ssDNA) viruses. dsDNA viruses primarily belong to two realms : Duplodnaviria and Varidnaviria , and ssDNA viruses are almost exclusively assigned to

267-410: A jelly roll fold folded structure in which the jelly roll (JR) fold is perpendicular to the surface of the viral capsid. Many members also share a variety of other characteristics, including a minor capsid protein that has a single JR fold, an ATPase that packages the genome during capsid assembly, and a common DNA polymerase . Two kingdoms are recognized: Helvetiavirae , whose members have MCPs with

356-700: A 22-fold increased risk of cervical cancer. The carcinogenic HPV types in cervical cancer belong to the alphapapillomavirus genus and can be grouped further into HPV clades . The two major carcinogenic HPV clades, alphapapillomavirus-9 (A9) and alphapapillomavirus-7 (A7), contain HPV16 and HPV18 , respectively. These two HPV clades were shown to have different effects on tumour molecular characteristics and patient prognosis, with clade A7 being associated with more aggressive pathways and an inferior prognosis. In 2020, about 604,000 new cases and 342,000 deaths from cervical cancer occurred worldwide. Around 90% of these occurred in

445-414: A consequence of replication of the viral genome. Eukaryotic ssDNA viruses are replicated in the nucleus. Most ssDNA viruses contain circular genomes that are replicated via rolling circle replication (RCR). ssDNA RCR is initiated by an endonuclease that bonds to and cleaves the positive strand, allowing a DNA polymerase to use the negative strand as a template for replication. Replication progresses in

534-416: A dsDNA genome. Lastly, some dsDNA viruses are replicated as part of a process called replicative transposition whereby a viral genome in a host cell's DNA is replicated to another part of a host genome. dsDNA viruses can be subdivided between those that replicate in the cell nucleus , and as such are relatively dependent on host cell machinery for transcription and replication, and those that replicate in

623-461: A few exceptions and peculiarities exist. The family Anelloviridae is the only ssDNA family whose members have negative sense genomes, which are circular. Parvoviruses, as previously mentioned, may package either the positive or negative sense strand into virions. Lastly, bidnaviruses package both the positive and negative linear strands. The International Committee on Taxonomy of Viruses (ICTV) oversees virus taxonomy and organizes viruses at

712-427: A group reported that, in frozen blood samples of 57 sexually naive pediatric patients who had vertical or transfusion-acquired HIV infection, 8 (14.0%) of these samples also tested positive for HPV-16. This seems to indicate that it may be possible for HPV to be transmitted via blood transfusion . However, as non-sexual transmission of HPV by other means is not uncommon, this could not be definitively proven. In 2009,

801-406: A group tested Australian Red Cross blood samples from 180 healthy male donors for HPV, and subsequently found DNA of one or more strains of the virus in 15 (8.3%) of the samples. However, it is important to note that detecting the presence of HPV DNA in blood is not the same as detecting the virus itself in blood, and whether or not the virus itself can or does reside in blood in infected individuals

890-527: A loop around the genome by means of extending the 3'-end of the positive strand, displacing the prior positive strand, and the endonuclease cleaves the positive strand again to create a standalone genome that is ligated into a circular loop. The new ssDNA may be packaged into virions or replicated by a DNA polymerase to form a double-stranded form for transcription or continuation of the replication cycle. Parvoviruses contain linear ssDNA genomes that are replicated via rolling hairpin replication (RHR), which

979-530: A major capsid protein (MCP) that has the HK97 fold. Viruses in the realm also share a number of other characteristics involving the capsid and capsid assembly, including an icosahedral capsid shape and a terminase enzyme that packages viral DNA into the capsid during assembly. Two groups of viruses are included in the realm: tailed bacteriophages, which infect prokaryotes and are assigned to the order Caudovirales , and herpesviruses, which infect animals and are assigned to

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1068-399: A person coughing. The pharynx moves food from the mouth to the esophagus. It also moves air from the nasal and oral cavities to the larynx . It is also used in human speech, as pharyngeal consonants are articulated here, and it acts as a resonating chamber during phonation. Inflammation of the pharynx, or pharyngitis , is the painful inflammation of the throat. Pharyngeal cancer

1157-480: A protein (also called E6) that simultaneously binds to two host cell proteins called p53 and E6-Associated Protein ( E6-AP ). E6AP is an E3 Ubiquitin ligase , an enzyme whose purpose is to tag proteins with a post-translational modification called Ubiquitin. By binding both proteins, E6 induces E6AP to attach a chain of ubiquitin molecules to p53, thereby flagging p53 for proteosomal degradation. Normally, p53 acts to prevent cell growth and promotes cell death in

1246-458: A rapid growth of cells on the outer layer of the skin. While cases of warts have been described since the time of ancient Greece, their viral cause was not known until 1907. Skin warts are most common in childhood and typically appear and regress spontaneously over the course of weeks to months. Recurring skin warts are common. All HPVs are believed to be capable of establishing long-term "latent" infections in small numbers of stem cells present in

1335-427: A realm: ssDNA viruses are classified into one realm and include several families that are unassigned to a realm: Oropharynx In humans, the pharynx is part of the digestive system and the conducting zone of the respiratory system . (The conducting zone—which also includes the nostrils of the nose , the larynx , trachea , bronchi , and bronchioles —filters, warms and moistens air and conducts it into

1424-552: A relation to a group of proteins that contain SJR folds, including the Cupin superfamily and nucleoplasmins . Marine viruses in Varidnaviria are ubiquitous worldwide and, like tailed bacteriophages, play an important role in marine ecology. Most identified eukaryotic DNA viruses belong to the realm. Notable disease-causing viruses in Varidnaviria include adenoviruses , poxviruses , and

1513-418: A replication origin site and move in opposite directions of each other, is widely used. A rolling circle mechanism that produces linear strands while progressing in a loop around the circular genome is also common. Some dsDNA viruses use a strand displacement method whereby one strand is synthesized from a template strand, and a complementary strand is then synthesized from the prior synthesized strand, forming

1602-456: A single vertical JR fold, and Bamfordvirae , whose members have MCPs with two vertical JR folds. Varidnaviria is either monophyletic or polyphyletic and may predate the LUCA. The kingdom Bamfordvirae is likely derived from the other kingdom Helvetiavirae via fusion of two MCPs to have an MCP with two jelly roll folds instead of one. The single jelly roll (SJR) fold MCPs of Helvetiavirae show

1691-401: A single-stranded DNA genome. ssDNA viruses have the same manner of transcription as dsDNA viruses. However, because the genome is single-stranded, it is first made into a double-stranded form by a DNA polymerase upon entering a host cell. mRNA is then synthesized from the double-stranded form. The double-stranded form of ssDNA viruses may be produced either directly after entry into a cell or as

1780-594: A virus. HPV is a group of more than 200 related viruses, which are designated by a number for each virus type. Some HPV types, such as HPV5, may establish infections that persist for the lifetime of the individual without ever manifesting any clinical symptoms. HPV types 1 and 2 can cause common warts in some infected individuals. HPV types 6 and 11 can cause genital warts and laryngeal papillomatosis . Many HPV types are carcinogenic . About twelve HPV types (including types 16, 18, 31, and 45) are called "high-risk" types because persistent infection has been linked to cancer of

1869-505: A wide range of HPV types and squamous cell carcinoma of the skin . In such cases, in vitro studies suggest that the E6 protein of the HPV virus may inhibit apoptosis induced by ultraviolet light . Nearly all cases of cervical cancer are associated with HPV infection, with two types, HPV16 and HPV18, present in 70% of cases. In 2012, twelve HPV types were considered carcinogenic for cervical cancer by

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1958-417: Is pharyngeal ( / ˌ f æ r ɪ n ˈ dʒ iː əl / or / f ə ˈ r ɪ n dʒ i əl / ). All vertebrates have a pharynx, used in both feeding and respiration. The pharynx arises during development in all vertebrates through a series of six or more outpocketings on the lateral sides of the head. These outpocketings are pharyngeal arches , and they give rise to a number of different structures in

2047-407: Is a cancer that originates in the neck and/or throat. Waldeyer's tonsillar ring is an anatomical term collectively describing the annular arrangement of lymphoid tissue in the pharynx. Waldeyer's ring circumscribes the naso- and oropharynx, with some of its tonsillar tissue located above and some below the soft palate (and to the back of the oral cavity). It is believed that Waldeyer's ring prevents

2136-408: Is a pathogen. The laryngopharynx, ( Latin : pars laryngea pharyngis ), also known as hypopharynx , is the caudal part of the pharynx; it is the part of the throat that connects to the esophagus. It lies inferior to the epiglottis and extends to the location where this common pathway diverges into the respiratory ( laryngeal ) and digestive ( esophageal ) pathways. At that point, the laryngopharynx

2225-418: Is among the most common cancers worldwide, causing an estimated 604,000 new cases and 342,000 deaths in 2020. About 90% of these new cases and deaths of cervical cancer occurred in low- and middle-income countries . Roughly 1% of sexually active adults have genital warts. Cases of skin warts have been described since the time of ancient Greece , but it was not until 1907 that they were determined to be caused by

2314-715: Is associated with an increasing number of head and neck cancers . This association is independent of tobacco and alcohol use. The local percentage varies widely, from 70% in the United States to 4% in Brazil. Engaging in anal or oral sex with an HPV-infected partner may increase the risk of developing these types of cancers. In the United States, the number of newly diagnosed, HPV-associated head and neck cancers has surpassed that of cervical cancer cases. The rate of such cancers has increased from an estimated 0.8 cases per 100,000 people in 1988 to 4.5 per 100,000 in 2012, and, as of 2021,

2403-432: Is believed to be specific to a specific strain of HPV. In addition to genital warts, infection by HPV types 6 and 11 can cause a rare condition known as recurrent laryngeal papillomatosis , in which warts form on the larynx or other areas of the respiratory tract. These warts can recur frequently, may interfere with breathing, and in extremely rare cases can progress to cancer. For these reasons, repeated surgery to remove

2492-441: Is beneficial, or who should get an anal Pap smear. HPV is associated with approximately 50% of penile cancers . In the United States, penile cancer accounts for about 0.5% of all cancer cases in men. HPV16 is the most commonly associated type detected. The risk of penile cancer increases 2- to 3-fold for individuals who are infected with HIV as well as HPV. Oral infection with high-risk carcinogenic HPV types (most commonly HPV 16)

2581-433: Is chiefly based on transcription of mRNA, viruses in each Baltimore group also typically share their manner of replication. Viruses in a Baltimore group do not necessarily share genetic relation or morphology. The first Baltimore group of DNA viruses are those that have a double-stranded DNA genome. All dsDNA viruses have their mRNA synthesized in a three-step process. First, a transcription preinitiation complex binds to

2670-433: Is continuous with the esophagus posteriorly. The esophagus conducts food and fluids to the stomach; air enters the larynx anteriorly. During swallowing, food has the "right of way", and air passage temporarily stops. Corresponding roughly to the area located between the 4th and 6th cervical vertebrae , the superior boundary of the laryngopharynx is at the level of the hyoid bone . The laryngopharynx includes three major sites:

2759-406: Is due to HPV, and two strains – HPV16 and HPV18 – account for 70% of all cases. HPV16 is responsible for almost 90% of HPV-positive oropharyngeal cancers . Between 60% and 90% of the other cancers listed above are also linked to HPV. HPV6 and HPV11 are common causes of genital warts and laryngeal papillomatosis . An HPV infection is caused by the human papillomavirus , a DNA virus from

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2848-441: Is less common for female genital HPV infection. Fingers-genital contact is a possible way of transmission but unlikely to be a significant source. Though it has traditionally been assumed that HPV is not transmissible via blood – as it is thought to only infect cutaneous and mucosal tissues – recent studies have called this notion into question. Historically, HPV DNA has been detected in the blood of cervical cancer patients. In 2005,

2937-402: Is lined by respiratory epithelium that is pseudostratified, columnar, and ciliated. Polyps or mucus can obstruct the nasopharynx, as can congestion due to an upper respiratory infection. The auditory tube , which connects the middle ear to the pharynx, opens into the nasopharynx at the pharyngeal opening of the auditory tube. The opening and closing of the auditory tubes serves to equalize

3026-436: Is lined by non-keratinized squamous stratified epithelium. The HACEK organisms ( H aemophilus , A ctinobacillus actinomycetemcomitans , C ardiobacterium hominis , E ikenella corrodens , K ingella ) are part of the normal oropharyngeal flora, which grow slowly, prefer a carbon dioxide-enriched atmosphere, and share an enhanced capacity to produce endocardial infections, especially in young children. Fusobacterium

3115-436: Is not fully understood. The relation between caudoviruses and herpesviruses is also uncertain: they may share a common ancestor or herpesviruses may be a divergent clade from the realm Caudovirales . A common trait among duplodnaviruses is that they cause latent infections without replication while still being able to replicate in the future. Tailed bacteriophages are ubiquitous worldwide, important in marine ecology, and

3204-426: Is noted. When the moray bites prey , it first bites normally with its oral jaws, capturing the prey. Immediately thereafter, the pharyngeal jaws are brought forward and bite down on the prey to grip it; they then retract, pulling the prey down the eel's esophagus, allowing it to be swallowed. Invertebrates also have a pharynx. Invertebrates with a pharynx include the tardigrades , annelids and arthropods , and

3293-552: Is similar to RCR. Parvovirus genomes have hairpin loops at each end of the genome that repeatedly unfold and refold during replication to change the direction of DNA synthesis to move back and forth along the genome, producing numerous copies of the genome in a continuous process. Individual genomes are then excised from this molecule by the viral endonuclease. For parvoviruses, either the positive or negative sense strand may be packaged into capsids, varying from virus to virus. Nearly all ssDNA viruses have positive sense genomes, but

3382-476: Is still unknown. As such, it remains to be determined whether HPV can or cannot be transmitted via blood. This is of concern, as blood donations are not currently screened for HPV, and at least some organizations such as the American Red Cross and other Red Cross societies do not presently appear to disallow HPV-positive individuals from donating blood. DNA virus A DNA virus is a virus that has

3471-484: The African swine fever virus . Poxviruses have been highly prominent in the history of modern medicine, especially Variola virus , which caused smallpox . Many varidnaviruses can become endogenized in their host's genome; a peculiar example are virophages , which after infecting a host, can protect the host against giant viruses . dsDNA viruses are classified into three realms and include many taxa that are unassigned to

3560-471: The International Agency for Research on Cancer : 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, and 59. One study found that 74% of squamous cell carcinomas and 78% of adenocarcinomas tested positive for HPV types 16 or 18. Persistent HPV infection increases the risk for developing cervical carcinoma. Individuals who have an increased incidence of these types of infection are women with HIV/AIDS, who are at

3649-413: The ascending pharyngeal artery . The primary neural supply is from both the vagus and glossopharyngeal nerves. The vagus nerve provides an auricular branch also termed "Arnold's nerve" which also supplies the external auditory canal, thus laryngopharyngeal cancer can result in referred ear pain . This nerve is also responsible for the ear-cough reflex in which stimulation of the ear canal results in

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3738-441: The cytoplasm , in which case they have evolved or acquired their own means of executing transcription and replication. dsDNA viruses are also commonly divided between tailed dsDNA viruses, referring to members of the realm Duplodnaviria , usually the tailed bacteriophages of the order Caudovirales , and tailless or non-tailed dsDNA viruses of the realm Varidnaviria . The second Baltimore group of DNA viruses are those that have

3827-523: The developing world . Most HPV infections of the cervix are cleared rapidly by the immune system and do not progress to cervical cancer (see below the Clearance subsection in Virology ). Because the process of transforming normal cervical cells into cancerous ones is slow, cancer occurs in people having been infected with HPV for a long time, usually over a decade or more (persistent infection). Furthermore, both

3916-547: The exhaled breath condensate (EBC), bronchial brushing and neoplastic lung tissue of cases, and found a presence of an HPV infection in 16.4% of the subjects affected by nonsmall cell lung cancer, but in none of the controls. The reported average frequencies of HPV in lung cancers were 17% and 15% in Europe and the Americas, respectively, and the mean number of HPV in Asian lung cancer samples

4005-404: The lungs ). The human pharynx is conventionally divided into three sections: the nasopharynx , oropharynx , and laryngopharynx . In humans, two sets of pharyngeal muscles form the pharynx and determine the shape of its lumen . They are arranged as an inner layer of longitudinal muscles and an outer circular layer. The upper portion of the pharynx, the nasopharynx, extends from the base of

4094-407: The mucous membrane . Two folds arise from the cartilaginous opening: The oropharynx lies behind the oral cavity, extending from the uvula to the level of the hyoid bone . It opens anteriorly, through the isthmus faucium , into the mouth, while in its lateral wall, between the palatoglossal arch and the palatopharyngeal arch , is the palatine tonsil . The anterior wall consists of the base of

4183-452: The oropharynx , larynx , vulva , vagina , cervix , penis , and anus . These cancers all involve sexually transmitted infection of HPV to the stratified epithelial tissue . HPV type 16 is the strain most likely to cause cancer and is present in about 47% of all cervical cancers, and in many vaginal and vulvar cancers, penile cancers, anal cancers, and cancers of the head and neck. The table below lists common symptoms of HPV infection and

4272-410: The pyriform sinus , postcricoid area, and the posterior pharyngeal wall. Like the oropharynx above it, the laryngopharynx serves as a passageway for food and air and is lined with a stratified squamous epithelium . It is innervated by the pharyngeal plexus and by the recurrent laryngeal nerve . The vascular supply to the laryngopharynx includes the superior thyroid artery , the lingual artery and

4361-424: The skull to the upper surface of the soft palate . It includes the space between the internal nares and the soft palate and lies above the oral cavity. The adenoids , also known as the pharyngeal tonsils, are lymphoid tissue structures located in the posterior wall of the nasopharynx. Waldeyer's tonsillar ring is an annular arrangement of lymphoid tissue in both the nasopharynx and oropharynx. The nasopharynx

4450-596: The DNA upstream of the site where transcription begins, allowing for the recruitment of a host RNA polymerase . Second, once the RNA polymerase is recruited, it uses the negative strand as a template for synthesizing mRNA strands. Third, the RNA polymerase terminates transcription upon reaching a specific signal, such as a polyadenylation site. dsDNA viruses make use of several mechanisms to replicate their genome. Bidirectional replication, in which two replication forks are established at

4539-632: The HPV infection and cervical cancer drive metabolic modifications that may be correlated with the aberrant regulation of enzymes related to metabolic pathways. Non-European (NE) HPV16 variants are significantly more carcinogenic than European (E) HPV16 variants. The risk for anal cancer is 17 to 31 times higher among HIV-positive individuals who were coinfected with high-risk HPV, and 80 times higher for particularly HIV-positive men who have sex with men. Anal Pap smear screening for anal cancer might benefit some subpopulations of men or women engaging in anal sex. No consensus exists, though, that such screening

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4628-686: The United States. Although JORRP rates are substantially higher if a woman presents with genital warts at the time of giving birth, the risk of JORRP in such cases is still less than 1%. Genital HPV infections are transmitted primarily by contact with the genitals, anus, or mouth of an infected sexual partner. Of the 120 known human papilloma viruses, 51 species and three subtypes infect the genital mucosa. Fifteen are classified as high-risk types (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 68, 73, and 82), three as probable high-risk (26, 53, and 66), and twelve as low-risk (6, 11, 40, 42, 43, 44, 54, 61, 70, 72, 81, and 89). Condoms do not completely protect from

4717-424: The appearance of genital HPV-related diseases in newborns is rare. However, the lack of appearance does not rule out asymptomatic latent infection, as the virus has proven to be capable of hiding for decades. Perinatal transmission of HPV types 6 and 11 can result in the development of juvenile-onset recurrent respiratory papillomatosis (JORRP). JORRP is very rare, with rates of about 2 cases per 100,000 children in

4806-406: The associated types of HPV. Available HPV vaccines protect against either two, four, or nine types of HPV. There are six prophylactic HPV vaccines licensed for use: the bivalent vaccines Cervarix , Cecolin , and Walrinvax ; the quadrivalent vaccines Cervavax and Gardasil ; and the nonavalent vaccine Gardasil 9 . All HPV vaccines protect against at least HPV types 16 and 18, which cause

4895-420: The barometric pressure in the middle ear with that of the ambient atmosphere. The anterior aspect of the nasopharynx communicates through the choanae with the nasal cavities. On its lateral wall is the pharyngeal opening of the auditory tube , somewhat triangular in shape and bounded behind by a firm prominence, the torus tubarius or cushion, caused by the medial end of the cartilage of the tube that elevates

4984-611: The basal level at the rank of realm. Virus realms correspond to the rank of domain used for cellular life but differ in that viruses within a realm do not necessarily share common ancestry , nor do the realms share common ancestry with each other. As such, each virus realm represents at least one instance of viruses coming into existence. Within each realm, viruses are grouped together based on shared characteristics that are highly conserved over time. Three DNA virus realms are recognized: Duplodnaviria , Monodnaviria , and Varidnaviria . Duplodnaviria contains dsDNA viruses that encode

5073-494: The body, such as the hands or feet, or even the inner thighs. A wide variety of HPV types can cause genital warts, but types 6 and 11 together account for about 90% of all cases. However, in total more than 40 types of HPV are transmitted through sexual contact and can infect the skin of the anus and genitals. Such infections may cause genital warts, although they may also remain asymptomatic. The great majority of genital HPV infections never cause any overt symptoms and are cleared by

5162-418: The cancers in the world. In the United States, high-risk HPVs cause 3% of all cancer cases in women and 2% in men. Risk factors for persistent genital HPV infections, which increases the risk for developing cancer, include early age of first sexual intercourse, multiple partners, smoking, and immunosuppression. Genital HPV is spread by sustained direct skin-to-skin contact, with vaginal, anal, and oral sex being

5251-401: The degradation of p53, induced by E6, promotes unregulated cell division, cell growth and cell survival, all characteristics of cancer. It is important to note, that while the interaction between E6, E6AP and p53 was the first to be characterized, there are multiple other proteins in the host cell which interact with E6 and assist the induction of cancer. Studies have also shown a link between

5340-418: The developing pharynx of amphioxi and hemichordates . However, the vertebrate pharynx is unique in that it gives rise to endoskeletal support through the contribution of neural crest cells. Pharyngeal jaws are a "second set" of jaws contained within the pharynx of many species of fish, distinct from the primary (oral) jaws. Pharyngeal jaws have been studied in moray eels where their specific action

5429-568: The development is not well understood. The specific types of HPV that are associated with EV are HPV5, HPV8, and HPV14. Sexually transmitted HPV is divided into two categories: low-risk and high-risk. Low-risk HPVs cause warts on or around the genitals. Type 6 and 11 cause 90% of all genital warts and recurrent respiratory papillomatosis that causes benign tumors in the air passages. High-risk HPVs cause cancer and consist of about twelve identified types. Types 16 and 18 are responsible for causing most of HPV-caused cancers. These high-risk HPVs cause 5% of

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5518-484: The development of cancer. Co-factors such as cigarette smoke can also enhance the risk of such HPV-related cancers. HPV is believed to cause cancer by integrating its genome into nuclear DNA . Some of the early genes expressed by HPV, such as E6 and E7, act as oncogenes that promote tumor growth and malignant transformation . HPV genome integration can also cause carcinogenesis by promoting genomic instability associated with alterations in DNA copy number. E6 produces

5607-501: The greatest risk of cervical cancer. The quadrivalent vaccines also protect against HPV types 6 and 11. The nonavalent vaccine Gardasil 9 provides protection against those four types (6, 11, 16, and 18), along with five other high-risk HPV types responsible for 20% of cervical cancers (types 31, 33, 45, 52, and 58). Skin infection (" cutaneous " infection) with HPV is very widespread. Skin infections with HPV can cause noncancerous skin growths called warts (verrucae). Warts are caused by

5696-445: The immune system in a matter of months. Moreover, people may transmit the virus to others even if they do not display overt symptoms of infection. Most people acquire genital HPV infections at some point in their lives, and about 10% of women are currently infected. A large increase in the incidence of genital HPV infection occurs at the age when individuals begin to engage in sexual activity. As with cutaneous HPVs, immunity to genital HPV

5785-468: The invasion of microorganisms from going into the air and food passages and this helps in the defense mechanism of the respiratory and alimentary systems. The word pharynx ( / ˈ f ær ɪ ŋ k s / ) is derived from the Greek φάρυγξ phárynx , meaning "throat". Its plural form is pharynges / f ə ˈ r ɪ n dʒ iː z / or pharynxes / ˈ f ær ɪ ŋ k s ə z / , and its adjective form

5874-409: The lung disease found that people with lung cancer had more types of HPV than noncancer patients did, and among lung cancer patients, the chances of having eight types of serious HPV were significantly increased. In addition, expression of HPV structural proteins by immunohistochemistry and in vitro studies suggest HPV presence in bronchial cancer and its precursor lesions. Another study detected HPV in

5963-404: The man's genitals infected the woman's hand with high-risk HPV, two where her hand infected his genitals, one where her genitals infected his hand, two each where he infected his own hand, and she infected her own hand. Hands were not the main source of transmission in these 25 couples, but they were significant. Partridge reports men's fingertips became positive for high risk HPV at more than half

6052-445: The most common methods. HPV infection can also spread from a mother to baby during pregnancy . There is no evidence that HPV can spread via common items like toilet seats, but the types that cause warts may spread via surfaces such as floors. HPV is not killed by common hand sanitizers and disinfectants, increasing the possibility of the virus being transferred via non-living infectious agents called fomites . HPV vaccines can prevent

6141-605: The most common methods. Occasionally, it can spread from manual sex or from a mother to her baby during pregnancy . HPV is difficult to remove via standard hospital disinfection techniques, and may be transmitted in a healthcare setting on re-usable gynecological equipment, such as vaginal ultrasound transducers. The period of communicability is still unknown, but probably at least as long as visible HPV lesions persist. HPV may still be transmitted even after lesions are treated and no longer visible or present. Although genital HPV types can be transmitted from mother to child during birth,

6230-546: The most common types of infection. To be most effective, inoculation should occur before the onset of sexual activity, and are therefore recommended between the ages of 9–13 years. Cervical cancer screening , such as the Papanicolaou test ("pap smear"), or examination of the cervix after applying acetic acid , can detect both early cancer and abnormal cells that may develop into cancer. Screening allows for early treatment which results in better outcomes. Screening has reduced both

6319-459: The mouth as the free apex of the rostral epiglottis lies dorsal to the soft palate in a normal horse. In ruminants , the tonsils are a compact mass that points towards the lumen of the pharynx. Pharyngeal arches are characteristic features of vertebrates whose origin can be traced back through chordates to basal deuterostomes who also share endodermal outpocketings of the pharyngeal apparatus. Similar patterns of gene expression can be detected in

6408-410: The number of cases and the number of deaths from cervical cancer. Genital warts can be removed by freezing . Nearly every sexually active individual is infected by HPV at some point in their lives. HPV is the most common sexually transmitted infection (STI) , globally. High-risk HPVs cause about 5% of all cancers worldwide and about 37,300 cases of cancer in the United States each year. Cervical cancer

6497-511: The order Herpesvirales . Duplodnaviria is a very ancient realm, perhaps predating the last universal common ancestor (LUCA) of cellular life. Its origins not known, nor whether it is monophyletic or polyphyletic. A characteristic feature is the HK97-fold found in the MCP of all members, which is found outside the realm only in encapsulins , a type of nanocompartment found in bacteria: this relation

6586-550: The origins of Duplodnaviria and Varidnaviria are less clear. Prominent disease-causing DNA viruses include herpesviruses , papillomaviruses , and poxviruses . The Baltimore classification system is used to group viruses together based on their manner of messenger RNA (mRNA) synthesis and is often used alongside standard virus taxonomy, which is based on evolutionary history. DNA viruses constitute two Baltimore groups: Group I: double-stranded DNA viruses, and Group II: single-stranded DNA viruses. While Baltimore classification

6675-563: The papillomavirus family. Over 200 types have been described. An individual can become infected with more than one type of HPV, and the disease is only known to affect humans. More than 40 types may be spread through sexual contact and infect the anus and genitals . Risk factors for persistent infection by sexually transmitted types include early age of first sexual intercourse , multiple sexual partners, smoking, and poor immune function . These types are typically spread by sustained direct skin-to-skin contact, with vaginal and anal sex being

6764-469: The presence of DNA damage. p53 also upregulates the p21 protein, which blocks the formation of the cyclin D/Cdk4 complex, thereby preventing the phosphorylation of retinoblastoma protein (RB), and in turn, halting cell cycle progression by preventing the activation of E2F . In short, p53 is a tumor-suppressor protein that arrests the cell cycle and prevents cell growth and survival when DNA damage occurs. Thus,

6853-691: The rate (26% per two years) as their genitals (48%). Winer reports 14% of fingertip samples from sexually active women were positive. Non-sexual hand contact seems to have little or no role in HPV transmission. Winer found all fourteen fingertip samples from virgin women negative at the start of her fingertip study. In a separate report on genital HPV infection, 1% of virgin women (1 of 76) with no sexual contact tested positive for HPV, while 10% of virgin women reporting non-penetrative sexual contact were positive (7 of 72). Sharing of possibly contaminated objects, for example, razors, may transmit HPV. Although possible, transmission by routes other than sexual intercourse

6942-717: The rate has continued to increase. Researchers explain these recent data by an increase in oral sex. This type of cancer is more common in men than in women. The mutational profile of HPV-positive and HPV-negative head and neck cancer has been reported, further demonstrating that they are fundamentally distinct diseases. Some evidence links HPV to benign and malignant tumors of the upper respiratory tract. The International Agency for Research on Cancer has found that people with lung cancer were significantly more likely to have several high-risk forms of HPV antibodies compared to those who did not have lung cancer. Researchers looking for HPV among 1,633 lung cancer patients and 2,729 people without

7031-728: The realm Monodnaviria , which also includes some dsDNA viruses. Additionally, many DNA viruses are unassigned to higher taxa. Reverse transcribing viruses, which have a DNA genome that is replicated through an RNA intermediate by a reverse transcriptase , are classified into the kingdom Pararnavirae in the realm Riboviria . DNA viruses are ubiquitous worldwide, especially in marine environments where they form an important part of marine ecosystems, and infect both prokaryotes and eukaryotes . They appear to have multiple origins, as viruses in Monodnaviria appear to have emerged from archaeal and bacterial plasmids on multiple occasions, though

7120-447: The realm are called CRESS-DNA viruses and have circular ssDNA genomes. ssDNA viruses with linear genomes are descended from them, and in turn some dsDNA viruses with circular genomes are descended from linear ssDNA viruses. Viruses in Monodnaviria appear to have emerged on multiple occasions from archaeal and bacterial plasmids , a type of extra-chromosomal DNA molecule that self-replicates inside its host. The kingdom Shotokuvirae in

7209-673: The realm likely emerged from recombination events that merged the DNA of these plasmids and complementary DNA encoding the capsid proteins of RNA viruses. CRESS-DNA viruses include three kingdoms that infect prokaryotes: Loebvirae , Sangervirae , and Trapavirae . The kingdom Shotokuvirae contains eukaryotic CRESS-DNA viruses and the atypical members of Monodnaviria . Eukaryotic monodnaviruses are associated with many diseases, and they include papillomaviruses and polyomaviruses , which cause many cancers, and geminiviruses , which infect many economically important crops. Varidnaviria contains DNA viruses that encode MCPs that have

7298-447: The skeletal, muscular, and circulatory systems. The structure of the pharynx varies across the vertebrates. It differs in dogs, horses, and ruminants. In dogs, a single duct connects the nasopharynx to the nasal cavity. The tonsils are a compact mass that points away from the lumen of the pharynx. In the horse, the auditory tube opens into the guttural pouch and the tonsils are diffuse and raised slightly. Horses are unable to breathe through

7387-407: The skin in the genital area is the most common sexually transmitted infection worldwide. Such infections are associated with genital or anal warts (medically known as condylomata acuminata or venereal warts), and these warts are the most easily recognized sign of genital HPV infection. The strains of HPV that can cause genital warts are usually different from those that cause warts on other parts of

7476-437: The skin. Although these latent infections may never be fully eradicated, immunological control is thought to block the appearance of symptoms such as warts. Immunological control is HPV type-specific, meaning an individual may become resistant to one HPV type while remaining susceptible to other types. Types of warts include: Common, flat, and plantar warts are much less likely to spread from person to person. HPV infection of

7565-445: The subject of much research. Herpesviruses are known to cause a variety of epithelial diseases, including herpes simplex , chickenpox and shingles , and Kaposi's sarcoma . Monodnaviria contains ssDNA viruses that encode an endonuclease of the HUH superfamily that initiates rolling circle replication and all other viruses descended from such viruses. The prototypical members of

7654-413: The tongue and the epiglottic vallecula ; the lateral wall is made up of the tonsil, tonsillar fossa, and tonsillar (faucial) pillars; the superior wall consists of the inferior surface of the soft palate and the uvula. Because both food and air pass through the pharynx, a flap of connective tissue called the epiglottis closes over the glottis when food is swallowed to prevent aspiration . The oropharynx

7743-425: The virus because the areas around the genitals including the inner thigh area are not covered, thus exposing these areas to the infected person's skin. Studies have shown HPV transmission between hands and genitals of the same person and sexual partners. Hernandez tested the genitals and dominant hand of each person in 25 heterosexual couples every other month for an average of seven months. She found two couples where

7832-606: The warts may be advisable. Cervical cancer is among the most common cancers worldwide, causing an estimated 604,000 new cases and 342,000 deaths in 2020. About 90% of these new cases and deaths of cervical cancer occurred in low- and middle-income countries , where screening tests and treatment of early cervical cell changes are not readily available. In the United States, about 37,300 cases of cancer due to HPV occur each year. In some infected individuals, their immune systems may fail to control HPV. Lingering infection with high-risk HPV types, such as types 16, 18, 31, and 45, can favor

7921-419: Was 35.7%, with a considerable heterogeneity between certain countries and regions. In very rare cases, HPV may cause epidermodysplasia verruciformis (EV) in individuals with a weakened immune system . The virus, unchecked by the immune system, causes the overproduction of keratin by skin cells , resulting in lesions resembling warts or cutaneous horns which can ultimately transform into skin cancer , but

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