Laryngeal papillomatosis is caused by human papillomavirus (HPV), most frequently by types 6 and 11. The mode of transmission is found to differ depending on age. The disease is typically separated into two forms, juvenile and adult papillomatosis, based on whether it develops before or after 20 years of age. The juvenile form is generally transmitted through contact with a mother’s infected vaginal canal during childbirth. Less is known about transmission in the adult form of this disease, though oral sex has been implicated as a potential mode of transmission. However, it is uncertain whether oral sex would directly transmit the virus or activate the dormant virus that was transmitted at childbirth.

In general, physicians are unsure why only certain people who have been exposed to the HPV types implicated in the disease develop laryngeal papillomatosis. In the case of the juvenile form of the disease, the likelihood of a child born of an infected mother developing laryngeal papillomatosis is low (between 1 in 231 to 1 in 400), even if the mother’s infection is active. Risk factors for a higher likelihood of transmission at childbirth include the first birth, vaginal birth, and teenage mother.

The evolution of laryngeal papillomatosis is highly unpredictable and is characterized by modulation of its severity and variable rate of progression across individuals. While instances of total recovery are observed, the condition is often persistent and lesions can reappear even after treatment. Factors that might affect the clinical course of the condition include: the HPV genotype, the age at onset, the elapsed time between the diagnosis and first treatment in addition to previous medical procedures. Other factors, albeit controversial, such as smoking or the presence gastroesophageal reflux disease might also play a role in the progression of the disease.

The papillomas can travel past the larynx and infect extralaryngeal sites. In more aggressive cases, infection of the lungs can occur with progressive airway obstruction. Although rare (less than 1% of people with laryngeal papillomatosis), transformation from a benign form to a malignant form is also observed. Death can result from these complications (morbidity rate is around 1-2%).

The etiology of florid cutaneous papillomatosis is unknown. It is likely directly induced by an underlying neoplasm secreting a growth factor. One candidate may be alpha-transforming growth factor, structurally related to epidermal growth factor, but antigenically distinct from it. The underlying cancer is most often gastric adenocarcinoma but also with breast cancer, bladder cancer, hepatobiliary cancer, ovarian cancer, uterine cancer, prostate cancer, lung cancer and cervical cancer. Other associated underlying malignancies include squamous cell carcinomas and lymphomas.

Florid cutaneous papillomatosis is almost twice as common in men than in women, and is usually diagnosed in individuals aged 53–72 years (mean patient age, 58.5 years).

There is currently a limited amount of information available on the incidence and prevalence of VCD, and the various rates reported in the literature are most likely an underestimate. Although VCD is thought to be rare overall, its prevalence among the population at large is not known.

However, numerous studies have been conducted on its incidence and prevalence among patients presenting with asthma and exertional dyspnea. A VCD incidence rate of 2% has been reported among patients whose primary complaint was either asthma or dyspnea; the same incidence rate has also been reported among patients with acute asthma exacerbation. Meanwhile, much higher VCD incidence rates have also been reported in asthmatic populations, ranging from 14% in children with refractory asthma to 40% in adults with the same complaint. It has also been reported that the VCD incidence rate is as high as 27% in non-asthmatic teenagers and young adults.

Data on the prevalence of VCD is also limited. An overall prevalence of 2.5% has been reported in patients presenting with asthma. Among adults with asthma considered "difficult to control", 10% were found to have VCD while 30% were found to have both VCD and asthma. Among children with severe asthma, a VCD prevalence rate of 14% has been reported. However, higher rates have also been reported; among one group of schoolchildren thought to suffer from exercise-induced asthma, it was found that 26.9% actually had VCD and not asthma. Among intercollegiate athletes with exercise-induced asthma, the VCD rate has been estimated at 3%.

In patients presenting with symptoms of dyspnea, prevalence rates ranging from 2.8% to 22% have been reported in various studies. It has been reported that two to three times more females than males suffer from VCD. VCD is especially common in females who suffer from psychological problems. There is an increased risk associated with being young and female. Among patients suffering from VCD, 71% are over the age of 18. In addition, 73% of those with VCD have a previous psychiatric diagnosis. VCD has also been reported in newborns with gastroesophageal reflux disorder (GERD).

OPA has been found in most countries where sheep are farmed, with the exception of Australia and New Zealand. OPA has been eradicated in Iceland.

No breed or sex of sheep appears to be predisposed to OPA. Most affected sheep show signs at 2 to 4 years of age.

OPA is not a notifiable disease, and therefore it is difficult to assess its prevalence.

High-risk carcinogenic HPV types (including HPV 16 and HPV 18) are associated with an increasing number of head and neck cancers.

Sexually transmitted forms of HPV account for about 25% of cancers of the mouth and upper throat (the oropharynx). The latter commonly present in the tonsil area, and HPV is linked to the increase in oral cancers in nonsmokers. Engaging in anal or oral sex with an HPV-infected partner may increase the risk of developing these types of cancers. Oral infection with several types of HPV, in particular type 16, have been found to be associated with HPV-positive oropharyngeal cancer, a form of head and neck cancer. This association is independent of tobacco and alcohol use. In the United States, HPV is expected to replace tobacco as the main causal agent for oral cancer, and the number of newly diagnosed, HPV-associated head and neck cancers is expected to surpass that of cervical cancer cases by 2020.

In recent years, the United States has experienced an increase in the number of cases of throat cancer caused by HPV type 16. Throat cancers associated with HPV have been estimated to have increased from 0.8 cases per 100,000 people in 1988 to 2.6 per 100,000 in 2004. Researchers explain these recent data by an increase in oral sex. Moreover, findings indicate this type of cancer is much more prevalent in men than in women, something that needs to be further explored. Currently, two immunizations, Gardasil and Cervarix, are recommended to girls to prevent HPV-related cervical cancer, but not as a precaution against HPV-related throat cancer.

The mutational profile of HPV-positive and HPV-negative head and neck cancer has been reported, further demonstrating that they are fundamentally distinct diseases.

Studies show a link between HPV infection and penile and anal cancers. Sexually transmitted HPVs are found in a large percentage of anal cancers. Moreover, the risk for anal cancer is 17 to 31 times higher among gay and bisexual men than among heterosexual men

- though one survey did not find a difference between the HPV infection rate of men who had sex with men versus those who had sex only with women.

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 is beneficial, or who should get an anal Pap smear.

Tracheobronchopathia osteochondroplastica (TO) is a rare benign disease of unknown cause, in which multiple cartilaginous or bony submucosal nodules project into the trachea and proximal bronchi. The nodules usually spare the posterior wall of the airway because they are of cartilaginous origin, while the posterior wall of the airway is membranous (does not contain cartilage). This is as opposed to tracheobronchial amyloidosis, which does not spare the posterior wall.

It usually occurs in men around their fifth decade of life, as opposed to tracheobronchial papillomatosis due to HPV infection, which usually occurs in younger patients. TO can cause airway obstruction, bleeding and chronic cough. Treatment involves the use of bronchodilators, and physical dilatation by bronchoscopy. The patients are also more prone to post-obstructive pneumonia and chronic lung infection in severe cases.

The differential of TO includes amyloidosis, which is typically circumferential, papillomatosis, though this usually occurs in younger patients and can cause lung cavitation when disseminated, granulomatosis with polyangiitis, though this is circumferential as well and often involves distal lung cavitation as well. Relapsing polychondritis can also spare the posterior wall, though it is not typically nodular in appearance.

The following increase an individual's chances for acquiring VCD:

- Upper airway inflammation (allergic or non-allergic rhinitis, chronic sinusitis, recurrent upper respiratory infections)

- Gastroesophageal reflux disease

- Past traumatic event that involved breathing (e.g. near-drowning, suffocation)

- Severe emotional trauma or distress

- Female gender

- Playing a wind instrument

- Playing a competitive or elite sport

Oral florid papillomatosis is a condition characterized by a white mass resembling a cauliflower covering the tongue and extending onto other portions of the mucous membranes. This is a type of verrucous carcinoma.

There is low or very-low quality evidence that probiotics may be better than placebo in preventing acute URTIs. Vaccination against influenza viruses, adenoviruses, measles, rubella, "Streptococcus pneumoniae", "Haemophilus influenzae", diphtheria, "Bacillus anthracis", and "Bordetella pertussis" may prevent them from infecting the URT or reduce the severity of the infection.

Tracheobronchomegaly is a very rare congenital disorder of the lung primarily characterized by an abnormal widening of the upper airways. The abnormally widened trachea and mainstem bronchi are associated with recurrent lower respiratory tract infection and copious purulent sputum production, eventually leading to bronchiectasis and other respiratory complications.

Pneumonia occurs in a variety of situations and treatment must vary according to the situation. It is classified as either community or hospital acquired depending on where the patient contracted the infection. It is life-threatening in the elderly or those who are immunocompromised. The most common treatment is antibiotics and these vary in their adverse effects and their effectiveness. Pneumonia is also the leading cause of death in children less than five years of age in low income countries. The most common cause of pneumonia is pneumococcal bacteria, "Streptococcus pneumoniae" accounts for 2/3 of bacteremic pneumonias. This is a dangerous type of lung infection with a mortality rate of around 25%.

For optimal management of a pneumonia patient, the following must be assessed: pneumonia severity (including treatment location, e.g., home, hospital or intensive care), identification of causative organism, analgesia of chest pain, the need for supplemental oxygen, physiotherapy, hydration, bronchodilators and possible complications of emphysema or lung abscess.

Bronchomalacia is a term for weak cartilage in the walls of the bronchial tubes, often occurring in children under six months. Bronchomalacia means 'floppiness' of some part of the bronchi. Patients present with noisy breathing and/or wheezing. There is collapse of a main stem bronchus on exhalation. If the trachea is also involved the term tracheobronchomalacia (TBM) is used. If only the upper airway the trachea is involved it is called tracheomalacia (TM). There are two types of bronchomalacia. Primary bronchomalacia is due to a deficiency in the cartilaginous rings. Secondary bronchomalacia may occur by extrinsic compression from an enlarged vessel, a vascular ring or a bronchogenic cyst. Though uncommon, idiopathic (of unknown cause) tracheobronchomalacia has been described in older adults.

Children have 2-9 viral respiratory illnesses per year. In 2013 18.8 billion cases of upper respiratory infections were reported. As of 2014, upper respiratory infections caused about 3,000 deaths down from 4,000 in 1990. In the United States, URIs are the most common infectious illness in the general population. URIs are the leading reasons for people missing work and school.

Bronchomalacia can best be described as a birth defect of the bronchus in the respiratory tract. Congenital malacia of the large airways is one of the few causes of irreversible airways obstruction in children, with symptoms varying from recurrent wheeze and recurrent lower airways infections to severe dyspnea and respiratory insufficiency. It may also be acquired later in life due to chronic or recurring inflammation resulting from infection or other airway disease.

Neonates with TEF or esophageal atresia are unable to feed properly. Once diagnosed, prompt surgery is required to allow the food intake. Some children do experience problems following TEF surgery; they can develop dysphagia and thoracic problems. Children with TEF can also be born with other abnormalities, most commonly those described in VACTERL association - a group of anomalies which often occur together, including heart, kidney and limb deformities. 6% of babies with TEF also have a laryngeal cleft.

Chronic lung disease develops in more than 25% of people with A-T. Three major types of lung disease can develop: (1) recurrent and chronic sinopulmonary infections; (2) lung disease caused by ineffective cough, swallowing dysfunction, and impaired airway clearance; and (3) restrictive interstitial lung disease. It is common for individuals with A-T to have more than one of these lung conditions. Chronic lung disease can occur because of recurrent lung infections due to immunodeficiency. Individuals with this problem are at risk of developing bronchiectasis, a condition in which bronchial tubes are permanently damaged, resulting in recurrent lower airway infections. Gamma globulin for people with antibody deficiency and/or chronic antibiotic treatment may reduce the problems of infection. Other individuals with A-T have difficulty with taking deep breaths and may have an ineffective cough, making it difficult to clear oral and bronchial secretions. This can lead to prolonged respiratory symptoms following common viral respiratory illnesses. Techniques that allow clearance of mucus can be helpful in some individuals during respiratory illnesses. Some people will develop swallowing problems as they age, increasing their risk of aspiration pneumonia. Recurrent injury to the lungs caused by chronic infections or aspiration may cause lung fibrosis and scarring. This process may be enhanced by inadequate tissue repair in ATM-deficient cells. A small number of individuals develop interstitial lung disease. They have decreased pulmonary reserve, trouble breathing, a need for supplemental oxygen and chronic cough in the absence of lung infections. They may respond to systemic steroid treatment or other drugs to reduce inflammation.

Lung function tests (spirometry) should be performed at least annually in children old enough to perform them, influenza and pneumococcal vaccines given to eligible individuals, and sinopulmonary infections treated aggressively to limit the development of chronic lung disease.

LPR is often regarded as a subtype of GERD that occurs when stomach contents flow upward through the esophagus and reach the level of the larynx and pharynx. However, LPR is associated with a distinct presentation of symptoms. LPR and GERD frequently differ in the relative prevalence of heartburn and throat clearing. While heartburn is present in over 80% of GERD cases, it occurs in only 20% of LPR cases. Throat clearing shows the opposite prevalence pattern, occurring in approximately 87% of LPR cases and in fewer than 5% of GERD cases. Unlike GERD, LPR also poses a risk for bronchitis or pneumonitis as reflux of stomach acid to the level of the larynx can result in aspiration. LPR is also commonly associated with erythema, or redness, as well as edema in the tissues of the larynx that are exposed to gastric contents. In contrast, most cases of GERD are nonerosive, with no apparent injury to the mucosal lining of the esophageal tissue exposed to the refluxed material.

Differences in the molecular structure of the epithelial tissue lining the laryngopharyngeal region may be partly responsible for the different symptomatic manifestations of LPR in comparison to GERD. In contrast to the resistant stratified squamous epithelium lining the esophagus, the larynx is lined by ciliated respiratory epithelium, which is more fragile and susceptible to damage. While the epithelium lining the esophagus is capable of withstanding as many as 50 instances of exposure to gastric contents each day, which is the uppermost estimate considered to be within the range of normal physiologic functioning, injury to laryngeal epithelium can occur following exposure to only small amounts of acidic gastric contents.

Lower respiratory infectious disease is the fifth-leading cause of death and the combined leading infectious cause of death, being responsible for 2·74 million deaths worldwide. This is generally similar to estimates in the 2010 Global Burden of Disease study.

This total only accounts for "Streptococcus pneumoniae" and "Haemophilus Influenzae" infections and does not account for atypical or nosocomial causes of lower respiratory disease, therefore underestimating total disease burden.

People with A-T have a highly increased incidence (approximately 25% lifetime risk) of cancers, particularly lymphomas and leukemia, but other cancers can occur. When possible, treatment should avoid the use of radiation therapy and chemotherapy drugs that work in a way that is similar to radiation therapy (radiomimetic drugs), as these are particularly toxic for people with A-T. The special problems of managing cancer are sufficiently complicated that treatment should be done only in academic oncology centers and after consultation with physicians who have specific expertise in A-T. Unfortunately, there is no way to predict which individuals will develop cancer. Because leukemia and lymphomas differ from solid tumors in not progressing from solitary to metastatic stages, there is less need to diagnose them early in their appearance. Surveillance for leukemia and lymphoma is thus not helpful, other than considering cancer as a diagnostic possibility whenever possible symptoms of cancer (e.g. persistent swollen lymph glands, unexplained fever) arise.

Women who are A-T carriers (who have one mutated copy of the ATM gene), have approximately a two-fold increased risk for the development of breast cancer compared to the general population. This includes all mothers of A-T children and some female relatives. Current consensus is that special screening tests are not helpful, but all women should have routine cancer surveillance.

LPR was not discussed as a separate condition from GERD until the 1970s and 1980s. However, at around the same time that GERD was first recognized as a clinical entity in the mid-1930s, a link between gut symptoms and airway disease was suggested. Later, acid-related laryngeal s and granulomas were reported in 1968. Subsequent studies suggested that acid reflux might be a contributory factor in other laryngeal and respiratory conditions. In 1979, the link between these airway symptoms and reflux of gastric contents was first documented. At the same time, treatment of reflux disease results was shown to eliminate these airway symptoms.

Long-term antibiotics, while they decrease rates of infection during treatment, have an unknown effect on long-term outcomes such as hearing loss. This method of prevention has been associated with emergence of antibiotic-resistant otitic bacteria. They are thus not recommended.

Pneumococcal conjugate vaccines (PCV) in early infancy, decreases the risk of acute otitis media in healthy infants. PCV is recommended for all children, and, if implemented broadly, PCV would have a significant public health benefit. Influenza vaccine is recommended annually for all children. PCV does not appear to decrease the risk of otitis media when given to high-risk infants or for older children who have previously experienced otitis media.

Risk factors such as season, allergy predisposition and presence of older siblings are known to be determinants of recurrent otitis media and persistent middle-ear effusions (MEE). History of recurrence, environmental exposure to tobacco smoke, use of daycare, and lack of breastfeeding have all been associated with increased risk of development, recurrence, and persistent MEE. Thus, cessation of smoking in the home should be encouraged, daycare attendance should be avoided or daycare facilities with the fewest attendees should be recommended, and breastfeeding should be promoted.

There is some evidence that breastfeeding for the first year of life is associated with a reduction in the number and duration of OM infections. Pacifier use, on the other hand, has been associated with more frequent episodes of AOM.

Evidence does not support zinc supplementation as an effort to reduce otitis rates except maybe in those with severe malnutrition such as marasmus.