When the tiny air sacs in our lungs, called alveoli, become infected with invading pathogens like bacteria, viruses, or fungi, the delicate balance of our respiratory system is disrupted. As the infection takes hold, the alveoli become inflamed and fill with fluid or pus, making it difficult for oxygen to reach the bloodstream. This is pneumonia – a serious and potentially life-threatening condition that affects millions of people worldwide. Fig 1: Picture depicting the difference between healthy lungs & inflamed lungs. Types of Pneumonia: Pneumonia is classified into different types based on the cause of infection and the type of agent responsible for the pneumonia. All of them are explained in detail below. Bacterial pneumonia: It is the most commonly emerging pneumonia. As the name indicates, it is caused by bacteria, and most commonly by the Streptococcus pneumoniae. Other bacteria involved in causing pneumonia include Pneumococcus bacteria, Mycoplasma, Chlamydia, and Legionella. Viral pneumonia: The viral pneumonia is often caused by different viruses like the Influenza virus, the Cold virus, RSV, Measles virus, adenovirus and Whooping cough virus. Fungal pneumonia: The fungal agents causing pneumonia include Coccidioidomycosis, Cryptococcus, and Histoplasmosis. Community-acquired pneumonia: Community-acquired pneumonia, mainly abbreviated as CAP, encompasses those patients with pneumonia who are living autonomously in a community. This type of pneumonia may happen because of poor hygienic conditions in the community. Health care-associated pneumonia: Health care-associated pneumonia, mainly abbreviated as HAP. As the name indicates, this type of pneumonia develops in the hospital setting. It can occur if the patient spends more time in the hospital. It can also be antibiotic-resistant pneumonia, and can be difficult to treat. Ventilator-associated pneumonia: Ventilator-associated pneumonia, mainly abbreviated as VAP. This type of pneumonia mainly arises when the patient is in a serious condition and is on a ventilator. The causal factor in VAP is the infestation caused by the ventilator itself. Signs & symptoms associated with pneumonia The person suffering from pneumonia usually exhibits the following indications, such as chest pain, shortness of breath, cough, fever, headache, and loss of appetite, etc. Pharmacological treatment options for pneumonia: If the patient is moderately sick with pneumonia and also is neither elderly nor suffering from contemporary systemic diseases of the heart, kidney, liver, or compromised immune system, then the patient is mainly considered as an outpatient. Such patients can be treated with antibiotics like macrolide (Azithromycin-500mg L.D. followed by 250mgOD from Day 2 to Day 5) and tetracycline (Doxycycline-100mg BD from Day 1 to Day 5). However, if the patient is in such a condition that suffering from multilobar infiltration, confusion, disorientation, uremia (blood urea nitrogen 20mg/dL), leukopenia (WBCs 4000cells/cubic mm, thrombocytopenia & hypothermia (temp 36 ) then needs to be admitted to hospital and needs non-ICU treatment. In this case, the patient is administered fluoroquinolone (moxifloxacin-400mg OD) & -lactam antibiotic (Ceftriaxone-1to2g IV OD for Day 1, 2 succeeded by 1 to 2g IM for 5 days) and macrolide (Azithromycin-500mg IV for Day 1, 2 followed by 500mg P.O for 5 days). Although if the patient is hypotensive and suffering from respiratory distress, then they must be admitted to the ICU and require the following treatment immediately: a -lactam antibiotic (Cefotaxime- 1to2g IV q 6-8hr) OR (Ampicillin-Sulbactam- 1.5to3g IV q 6hr for 1 to 2 weeks) and Macrolide (Azithromycin- 500mg IV for Day 1, 2 succeeded by 500mg P.O for 5 days). In case if the patient is allergic to penicillin, then fluoroquinolone (moxifloxacin- 400mg OD for 1 to 2 weeks) & -lactam antibiotic (Aztreonam- 2g IV q6-8hr for 1 to 2 weeks) is administered. Non-pharmacological management of pneumonia: The pneumonia can be prevented non-pharmacologically by following such simple tips: Abstaining from smoking. Evading alcoholism. Exercising healthy sanitation. Conclusion: Overall, pneumonia is a severe disorder of the respiratory tract system. It can vary from person to person based on the causal factor. It can be life-threatening, but proper diagnosis and on-the-spot treatment can help patients recover from this disease. A quote as a concluding note; ‘‘The Ability to breathe is a gift’’ FAQs: Is pneumonia contagious? Yes, pneumonia is a contagious disease. It can spread from one person to another through coughing, sneezing, or touching surfaces infected with pneumonia-causing bacteria, viruses, or fungi. What type of people are at increased risk of this disease? Older people, infants, and people with a weak immune system are at higher risk of getting pneumonia. What are the diagnostic tests for pneumonia? A chest X-ray is the diagnostic tool for pneumonia. It provides clear information about the inflammation in the lungs, etc. What are the vaccines to avoid pneumonia, and when should these vaccines be administered? Yes, there are vaccines, which can help prevent this disease. These are the flu vaccine and the pneumococcal vaccine. The 1st one is usually administered once every year. While the 2nd one is usually administered once & then repeated every 5 years. Can pneumonia be seasonal? Yes, pneumonia is a seasonal disease. It mainly emerges in cold weather. That’s why the fall & winter weather is also called pneumonia season, and children can mostly get affected by pneumonia in this season. References: [1] L. R. et al Baden, “Overview of Pneumonia,” Goldman-Cecil Medicine, vol. 1. pp. 606–619, 2024. [2] “Pneumonia_ Symptoms, Causes, and Treatment.” [3] K. Batra, K. Jordan, S. Fisher, and S. Abbara, “Normal Anatomy of the Lungs | Radiology Key,” Problem Solving in Chest Imaging, no. Ivc. pp. 2–17, 2021.