Acute Interstitial Pneumonitis can result from many different irritants in the lungs and usually is resolved in under a month. Chemical Pneumonitis is caused by toxic substances reaching the lower airways of the bronchial tree. This causes a chemical burn and severe inflammation. (oxford)
Radiation Pneumonitis, also known as Radiation Induced Lung Injury, describes the initial damage done to the lung tissue by ionization radiation. Radiation, used to treat cancer, can cause pneumonitis when applied to the chest or full body. Radiation pneumonitis occurs in approximately 30% of advanced lung cancer patients treated with radiation therapy. Aspiration pneumonitis is caused by a chemical inhalation of harmful gastric contents which include causes such as:
Aspiration due to a drug overdose
A lung injury after the inhalation of habitual gastric contents. The development of colonized oropharyngeal material after inhalation. Bacteria entering the lungs

Treatment
Typical treatment for pneumonitis includes conservative use of corticosteroids such as a short course of oral prednisone or methylprednisolone. Inhaled corticosteroids such as fluticasone or budesonide may also be effective for reducing inflammation and preventing re-inflammation on a chronic level by suppressing inflammatory processes that may be triggered by environmental exposures such as allergens. Severe cases of pneumonitis may require corticosteroids and oxygen therapy, as well as elimination of exposure to known irritants.Corticosteroid dose and treatment duration vary from case to case.
The Centers for Disease Control and Prevention (CDC) recommends all teenagers receive MenACWY vaccine and booster, with optional MenB. MenACWY and MenB are also recommended for people of other ages with various medical conditions and social risk factors.A meningococcal polysaccharide vaccine (MPSV4) has been available since the 1970s and is the only meningococcal vaccine licensed for people older than 55. MPSV4 may be used in people 2–55 years old if the MCV4 vaccines are not available or contraindicated. Two meningococcal conjugate vaccines (MCV4) are licensed for use in the U.S. The first conjugate vaccine was licensed in 2005, the second in 2010. Conjugate vaccines are the preferred vaccine for people 2 through 55 years of age. It is indicated in those with impaired immunity, such as nephrotic syndrome or splenectomy. In June 2012, the U.S. Food and Drug Administration (FDA) approved a combination vaccine against two types of meningococcal diseases and Hib disease for infants and children 6 weeks to 18 months old. The vaccine, Menhibrix, was designed to prevent disease caused by Neisseria meningitidis serogroups C and Y, and Haemophilus influenzae type b (Hib). It was the first meningococcal vaccine that could be given to infants as young as six weeks old.In October 2014 the FDA approved the first vaccine effective against serogroup B, named Trumenba, for use in 10- to 25-year-old individuals. Africa
In 2010, the Meningitis Vaccine Project introduced a vaccine called MenAfriVac in the African meningitis belt.