Respiratory Health

  • URTI : Upper Respiratory Tract Infections
  • LRTI : Lower Respiratory Tract Infections
  • AECOPD : Acute Exacerbations in Chronic Obstructive Pulmonary Disease

Upper Respiratory Tract Infections

Otitis is a general term for infection or inflammation of the ear, usually bacterial (98%) and occasionally fungal or viral. It is part of upper respiratory infections (URI). Ear infections do not spread from person to person and they most commonly occur as a surinfection following a cold. Antibiotics are often used to treat ear infections.

Different forms of otitis can be found :

Otitis externa (acute, chronic or malignant) which involves the outer ear and ear canal.

Otitis media (acute, chronic, with effusion) which involves the middle ear with a localisation just behind the eardrum. The usual symptomatic presentation is known as acute otitis media and is characterized often by fever, irritability, otorrhea, letargy, vomiting, diarrhoea and hearing loss in some children. Otitis media is the second most common childhood disease and it can occur at any age. It is estimated that over 80 % of children would have experienced at least one episode before the age of 2.

Anatomy of the ear

Otitis interna (Labyrinthitis) is an inflammation of the inner ear when bacteria move from the naso-pharynx to reach the level of the alignment of the ear.

The annual incidence of acute otitis externa is between 1/100 and 1/250 of the general population and 256/1000 for acute otitis media in European children under 5 years.

Main bacteria involved in OTITISOtitis externaOtitis mediaOtitis interna
Pseudomonas aeruginosa, Staphylococcus aureus, CandidaStreptococcus pneumoniae,
Haemophilus influenzae,
Staphylococcus aureus,
Moraxella catarrhalis
Mycoplasma pulmonis,
Streptobacillus moniliformis,
Pseudomonas aeruginosa

The most common bacteria responsible for Otitis Externa, Media and Interna

Rhino-sinusitis (or sinusitis) is an inflammation or infection of the lining of the sinus cavities, triggered by a viral, bacterial or fungal infection. It is one of the most common upper respiratory tract infection, affecting an estimated 16% of the US adult population. In Europe, acute sinusitis affects an estimated 2 % and chronic rhino-sinusitis 10 % of the adult population.

Sinusitis can be :

  • Acute, which is usually caused by a bacterial infection in the sinuses that results from an upper respiratory tract infection.
  • Sub-acute or chronic, which refers to long-term swelling and inflammation of the sinuses that may be caused by bacteria (such as Staphylococcus aureus) or fungus and may involve allergy, environmental factors (pollution…).
The different sinusitis
AcuteSymptoms last for up to 4 weeks
Sub-acuteSymptoms last for 4-12 weeks
ChronicSymptoms last for 3 months or longer
Paranasal sinuses
Main pathogens involved in Rhino-sinusitis
BacteriaStreptococcus pneumoniae (30-35%), Haemophilus influenzae (20-25 %), Moraxella catarrhalis (20%), Staphylococcus aureus
VirusesRhinovirus, Influenza A et B, Parainfluenza, Coronavirus (which are the primary pathogens), Respiratory Syncytial Virus, Adenovirus and Enterovirus
FungiAspergillus, Alternaria, Bipolaris and Curvularia species

The most common pathogens responsible for Rhino-sinusitis

Tonsillitis is an inflammation of the glands of the throat. It is mostly caused by viruses, and, in 10 to 30 % of cases, by bacteria. The tonsils are two glands located in the back of the throat that help to protect the body from upper respiratory infections. In Europe, the prevalence in community studies is estimated to 2-4 % (20 000 – 40 000 individuals per million population).

Tonsillitis is mainly transmitted from one person to another by social contact, by droplets in the air from sneezing. The symptoms of tonsillitis are essentially fever, sore throat, pain when swallowing, headache. In some cases, complications are possible, they include cervical adenitis and tonsil abscess.

Different treatments exist to reduce tonsillitis symptoms :

  • Use of paracetamol / ibuprofen or anti-inflammatory drugs (eg, corticosteroids).
  • When tonsillitis is caused by bacteria, use of antibiotics such as penicillin or amoxicillin.
Tonsillitis
Main pathogens involved in Tonsillitis
VirusesAdenovirus, Rhinovirus, Influenza, Coronavirus, Respiratory Syncytial Virus.

It can also be caused by Epstein-Barr Virus, Herpes Simplex Virus, Cytomegalovirus, or HIV.
BacteriaStaphylococcus aureus, Streptococcus pyogenes, Streptococcal pharyngitis, Staphylococcus pneumoniae, Mycoplasma pneumoniae, Chlamydia pneumoniae, Pertussis, Fusobacterium, Diphtheria, Syphilis and Gonorrhea.

The most common pathogens responsible for Tonsillitis

Laryngitis is the medical term for inflammation and swelling of the larynx, characterized by voice loss and irritation of the vocal cords.

There are two types of laryngitis : acute or chronic.

Acute laryngitis is usually caused by an infection that inflames the vocal cords, but may also be caused by voice overuse with excess talking, singing or shouting.

Chronic laryngitis lasts over a week and comes back over time. It can be caused by :

  • Acid reflux, which leads to laryngeal inflammation and chronic cough (known as Gastroesophageal reflux disease).
  • Irritation, due for example to allergies, smoke, prolonged alcohol use or excess coughing.
  • Rarely, chronic laryngitis can provoke cancer of the throat and tumor on the vocal cords.
The different Laryngitis
AcuteUsually lasts for ‹ 7 days
ChronicPersistence of symptoms for 3 weeks or longer
Representation of Larynx

The most common cause of laryngitis is an infection, which could be either viral (which the most common virus is Rhinovirus), bacterial and rarely, a person may develop laryngitis from a fungal infection.

Main pathogens involved in Laryngitis
VirusesRhinovirus, Parainfluenza Virus, Respiratory Syncytial Virus, Influenza and Adenoviruses
BacteriaMoraxella catarrhalis, Haemophilus influenzae, Streptococcus pneumoniae, Staphylococcus aureus, and Klebsiella pneumoniae
FungiCandida species, or Histoplasma capsulatum, Blastomyces dermatitis and Cryptococcus neoformans.

The most common pathogens responsible for Laryngitis

Epiglottitis is an inflammation of the epiglottis (flap of tissue that sits at the base of the tongue that keeps food from going into the trachea during swallowing). When it becomes infected and inflamed, it can swell and obstruct or close off the windpipe which may be fatal unless promptly treated.

Conditions that cause epiglottitis include infectious, chemical and traumatic agents :

  • Infectious causes are the most common, classically with Haemophilus influenzae, but also from other potential pathogens.
  • Other types of epiglottitis that are environmental and not caused by infection include heat damage that may injure the epiglottis, called thermal epiglottitis and in rare instance, epiglottitis may be causes by allergic reactions to food.
Representation of Epiglottis
Main pathogens involved in Epiglottitis
BacteriaHaemophilus influenzae (25%), Streptococcus pneumoniae and Staphylococcus aureus
VirusesHerpes Simplex Virus type 1 and Parainfluenza virus
FungiCandida and Aspergillus

The most common pathogens responsible for Epiglottitis

Lower Respiratory Tract Infections

Pneumonia is an inflammation of the lungs associated with different factors such as fever, chest symptoms and consolidation or interstitial lung infiltrates. This disease can be caused by different types of microorganisms and can range in seriousness from mild to life-threatening. Currently, over 3 million people develop pneumonia each year and it is the sixth leading cause of death in the United States. In Europe, the annual cost is estimated to 10.1 billion euros and the incidence of the disease is 10.8/1000 people/year in Finland, 4.7/1000 in Great-Britain and 2.6/1000 in Spain.

There are different categories of pneumonia :

  • Bacteria are the most common cause of community acquired pneumonia, with Streptococcus pneumoniae isolated in 50 % of cases,
  • Viruses pneumonia,
  • Fungal pneumonia
Gram staining of Streptococcus pneumoniae R1014 : gram-positive alpha-hemolytic aerotolerant anaerobic bacteria
Main pathogens involved in Pneumonia
BacteriaStreptococcus pneumoniae, Haemophilus influenzae, Chlamydophila pneumoniae, Mycoplasma pneumoniae, Staphylococcus aureus, Moraxella catarrhalis, Legionella pneumophila.
VirusesRhinovirus, Coronavirus, Influenza virus, Respiratory Syncytial virus, Adenovirus, Pneumonia, Parainfluenza and Herpes Simplex virus.
FungiHistoplasma capsulatum, Blastomyces, Cryptococcus neoformans, Pneumocystis jiroveci and Coccidioides immitis.

The most common pathogens responsible for Pneumonia

Bronchitis is an inflammation of the main air passages to the lungs and is defined as a lower respiratory tract infection.

Two types of Bronchitis exist, acute bronchitis and chronic bronchitis. Chronic bronchitis has a prevalence of 3.5 % in the French general population aged ›= 45 and is an indicator of an increased risk of devoloping chronic obstructive pulmonary disease (COPD), which is developed in COPD part.

Acute bronchitis is characterized by the development of a cough and mucus most oftenly caused by viral infection of the epithelium of the bronchi. It results in an inflammation and increased secretion of mucus.

Almost 5 % of the general population develops acute bronchitis annualy in the US, with the highest incidence during the fall and winter months. Acute bronchitis generally follows a viral respiratory infection (90 %) and sometimes, a bacterial infection (10%).

The different Bronchitis
AcuteLasts under 21 days
ChronicWhen at least 3 months per year in two consecutive years
Representation of respiratory system
Main pathogens involved in Bronchitis
VirusesCoronavirus, Rhinovirus, Respiratory Syncytial Virus, Adenovirus, Influenza Virus, Para-influenza Virus
BacteriaChlamydia pneumoniae, Mycoplasma pneumoniae, Haemophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis.

The most common pathogens responsible for acute Bronchitis

Acute Exacerbation Chronic obstructive pulmonary disease (AECOPD) is one of the most common lung diseases. It is a progressive Chronic disease which is characterised by a decline in respiratory function and the worsening of symptoms provoke what are known as exacerbation.

The frequence of exacerbations has an impact on individual’s life expectancy. Moreover, they represent a significant cause of hospital admission and readmission. Acute exacerbations are an important cause of mortality and morbidity in patients with AECOPD.

AECOPD is the fourth leading cause of death and affects over 210 million people worldwide. In Europe, the prevalence in adult population has been estimated between 4-10 % . The development of AECOPD is not completely understood and may also depend on gender, genetic and socioeconomic factors (exposures to dusts, chemicals, pollutants).

The principal risks factor associated with AECOPD are :

  • Smoking, (50 % of chronic smokers develop AECOPD).
  • Air pollution and chemical fumes or dust from the environment.
  • Genetics, in rare cases (deficiency of a protein which is called alpha-1 antitrypsin).

Two main forms of COPD exist : chronic bronchitis and emphysema :

  • Chronic bronchitis is a cough with sputum production on most days during 3 months per year, for two consecutive years.
  • Emphysema is an enlargement of the air spaces distal to the terminal bronchioles with destruction of their walls (which reduces the surface available for the exchange of oxygen and carbon dioxide).

Acute exacerbations of COPD (AECOPD) are commonly triggered by bacterial or viral pathogens and also pollutants. Typically, infections cause 75% or more of the exacerbations, bacteria alone can be found in roughly 25% of cases, viruses in another 25%, and viruses and bacteria coinfection in another 25%.

Furthermore, other factors may provoke exacerbations, such as environmental pollution (nitrogen dioxide)

Main pathogens involved in AECOPD
VirusesRhinovirus (66%), Influenza, Parainfluenza, Coronavirus Adenovirus, Respiratory Syncytial Virus, Picornavirus, Metapneumovirus.
BacteriaHaemophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis, Haemophilus parainfluenzae, Pseudomonas aeruginosas.

The most common pathogens responsible for AECOPD

Main viruses

  • Rhinovirus (66%)
  • Influenza
  • Parainfluenza
  • Respiratory syncitial virus
  • Picornavirus
  • Metapneumovirus
  • Coronavirus

Main bacteria

  • Noncapsulated Haemophilus influenzae
  • Moraxella catharrhalis
  • Streptococcus pneumoniae
  • Pseudomonas aeruginosa

Tuberculosis is an infection caused by the koch bacillus Mycoplasma tuberculosis which attacks the lungs but may involve any other body part, especially bones and brain in case of inadequate containment by the immune system. Various tuberculosis causes exist, among them: weak immune system, poverty, vicious life, no strict hygiene, alcoholism. In 2008, there was an estimated 9.4 million incident cases of tuberculosis and the prevalence of the disease is estimated to be 200 per 100 000 population in the world. In Europe, the number of tuberculosis cases was 322 310 in 2008 and the annual cost is estimated to 2.1 billion euros per year.

Tuberculosis bacteria are transmitted through air from one person to another via small droplets of saliva produced when speaking, coughing, sneezing.

When the inhaled tuberculosis bacteria enter the lungs, they can multiply and cause a local lung infection (pneumonia). In most patients, within weeks from infection, the immune system limits propagation of tuberculosis infection resulting in asymptomatic that may remain in the body for many years. About 5 % of infected persons will develop the disease.

 

Estimate of TB incidence by country in 2008.
WHO report 2009 global tuberculosis control