There are 2 main types of pneumonitis:

Infectious Pneumonitis aka Pneumonia – A lung infection that causes inflammation and swelling of the air sacs in the lungs. The type of infection can vary, and may include viruses, bacteria, and fungi. Bacterial infections include Streptococcus pneumoniae, Haemophilus influenza type B, Chlamydia pneumoniae, Legionella spp., and Mycoplasma pneumoniae, while viral infections include respiratory syncytial virus (RSV) and the influenza virus.      

Non-Infectious Pneumonitis – This occurs from, for example, inhaling substances or toxins that irritate the lungs. Such substances include smoke, dust, and some volatile chemicals. Additionally, certain (few) antibiotics, chemotherapy drugs, and anti-arrhythmic medications can also produce pneumonitis.

Pneumonitis can occur at any age; however, infectious cases (pneumonia) are common among children under 2 years of age and older adults.
Pneumonia is also quite common among those with underlying risk factors:

• Hospital patients, especially those in the intensive care unit (ICU)
• People suffering from chronic diseases such as diabetes, asthma, chronic obstructive pulmonary disease (COPD), and heart disease
• People with compromised immune systems, such as those with HIV/AIDS, organ transplant recipients, cancer patients receiving chemotherapy, or those with a history of prolonged use of immunosuppressive medications    
• Smokers

People can contract pneumonia through:

• Airborne transmission; being coughed on, sneezed on, or breathed on by an infected person. These are ways to get the infection directly into the lungs
• Choking, in which saliva and food bits can bring infection from the upper respiratory tract into the lungs. This is often an issue among older adults and chronic disease sufferers
• Bloodstream infection, for example, contracting the infection from prolonged urinary catheterization or intravenous (IV) administration
• Infection from an abscess near the lungs, for example, a liver abscess

Infection through hospital test equipment such as an unsterile bronchoscopy, unclean pulmonary function equipment, or contaminated nebulizer. Infection can also spread by improper hand washing by medical personnel

 

Diagnosing pneumonia initially involves a thorough medical history review alongside checking for symptoms such as coughing with sputum production, fever, shortness of breath, and wheezing. The doctor will use a stethoscope to assess the lungs (auscultation) and may request a chest X-ray. Additionally, a blood test may be used to determine the cause of the pneumonia. The blood test may involve:

• White Blood Cell (WBC) Count – This can help determine if there is an infection from bacteria or a virus, although the test cannot identify the specific type of infection
• Blood Oxygen Level Test – This measures the ability of the lungs in getting oxygen into the blood
• Sputum and Blood Culture Tests – These tests determine the type of infectious agent

No matter the causative agent, symptoms are generally similar.
Symptoms of pneumonia may include: 

• Coughing with phlegm
• Chest pain while breathing and coughing
• Rapid breathing / difficulty breathing
• Fever, sweating, chills
• Nausea, vomiting
• Fatigue
• Obtundation (altered consciousness) and confusion, fall in body temperature in older adults
• Bloating, aversion to drinking water or milk in very young children

The severity of symptoms will vary from person to person depending on the specific causes of infection, age, and individual health.

Treatment of pneumonia involves simultaneously treating the condition and preventing possible complications.
Treatment may include the following methods:

• Antibiotics – For bacterial infections, the doctor will prescribe antibiotics based on the type of bacterial infection, which is determined by cultures and clinical-epidemiological data. It is important to note that prolonged use of antibiotics can increase resistance of certain bacteria, such as Streptococcus pneumoniae.   
• Symptom-based treatment – As symptoms present themselves, the doctor may prescribe fever-reducing medications, bronchodilators, and expectorants. Intravenous fluid and oxygen therapy or chest physical therapy (CPT) may be given in severe cases. 
• Treatment of complications – Bacteria may travel from the lungs into the bloodstream to other organs. Some people may experience pleural effusion (fluid build-up in the space between the lungs and chest wall, which may need drainage) or lung abscesses. In severe cases, patients can experience potentially fatal respiratory failure and require breathing assistance.

Pneumonitis, especially infectious pneumonitis (pneumonia), has the potential of being life-threatening. The following methods can help with pneumonia prevention:

• Getting vaccinated – Doctors recommend that those in high risk groups such as children, adults over 65, and those with compromised immune systems get vaccinated for prevention of pneumonia; vaccines include the influenza and pneumococcal vaccines.

Regarding pneumococcal vaccines, protection specifically against Streptococcus pneumonia is highly recommended; 2 vaccines are available, which include: 

• Pneumococcal Polysaccharide Vaccine (PPV) – This is recommended for high risk persons and older adults; should be taken every 5 years
• Pneumococcal Conjugate Vaccine (PCV)  – This protects against several strains of pneumococci: PCV 7, PCV 10, which are recommended for children 6 weeks to 5 years of age, and PCV 13, which is recommended for those in high risk groups and older adults 

Those in high risk groups can take both the influenza and pneumococcal vaccines during the same appointment, having one shot in each arm. After the vaccination, patients may feel a bit of discomfort at the area where the shot was administered; generally the discomfort usually subsides in 2-3 days. 

Adopting the following lifestyle habits may help prevent contracting pneumonia:

• Do not smoke, as tobacco smoke harms the lungs’ natural defense mechanism against infection; avoid being around cigarette smoke, smoke from fires, automobile exhaust, and cold weather
• Practice good hygiene, wash your hands frequently, and try to avoid crowded areas
• If suffering from a cold or flu, get treated quickly and do not let the condition persist
• Strengthen your immune system by getting sufficient sleep, eating healthy foods, and getting regular exercise
• Be aware of the dangers of excessive alcohol consumption, which can lead to aspiration pneumonia, which develops from liquid, food, vomit, or saliva being inhaled into the lungs.