What Can Cause Pneumonia?

Experts explain what’s most likely to cause pneumonia—and ways you can avoid getting the lung infection.

Pneumonia is a common respiratory infection that affects people of all ages, causing symptoms such as trouble breathing, chest pain, cough, and fever. While these symptoms are similar regardless of the cause, understanding the underlying factors responsible for your pneumonia can be crucial in effectively treating the condition. Pneumonia is characterized by inflammation and fluid buildup in the alveoli, tiny air sacs within the lungs. It can range from mild to severe, with certain individuals being more susceptible, especially those who smoke or have preexisting health conditions like diabetes or heart disease.

Prevention plays a key role in reducing the risk of pneumonia. Vaccinations, good hand hygiene, and regular disinfection of frequently touched surfaces can help protect against various types of pneumonia. Despite preventive measures, pneumonia remains a significant health concern, with more than 47,000 people succumbing to the condition in the United States in 2020.

To safeguard yourself against pneumonia, it’s essential to familiarize yourself with the primary causes of this lung infection. In this comprehensive guide, we will delve into the three main categories of pneumonia, providing insights into the causes, symptoms, and treatments associated with each.

Bacterial Pneumonia

Bacterial pneumonia is primarily instigated by the bacterium Streptococcus pneumoniae. This bacterium typically colonizes the upper respiratory tract. The symptoms of bacterial pneumonia can be severe and may include fever, chills, sweating, coughing, rapid or labored breathing, and chest pain. It can develop as a complication of a viral infection, such as the common cold or influenza, or result from aspirating fluids like saliva or vomit into the lungs.

In some cases, bacterial pneumonia can be triggered by a viral infection that disrupts the balance of bacteria in the lungs. It’s worth noting that the lungs are not entirely sterile, and they harbor harmless bacteria under normal circumstances. In addition to Streptococcus pneumoniae, other bacteria that can cause bacterial pneumonia include Staphylococcus aureus, Group A Streptococcus, Klebsiella pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis.

There are also bacteria that cause “atypical pneumonia,” which are challenging to detect through standard diagnostic methods. These atypical bacteria encompass Legionella pneumophila, responsible for Legionnaires’ disease, as well as Mycoplasma pneumoniae, Chlamydia pneumoniae, and Chlamydia psittaci.

Treatment for bacterial pneumonia typically involves antibiotics, with the choice of medication depending on the specific bacteria responsible for the infection. In severe cases, broad-spectrum antibiotics may be employed to target multiple types of bacteria. To lower the risk of contracting bacterial pneumonia caused by Streptococcus pneumoniae, individuals can receive pneumococcal vaccines, of which there are two varieties available in the United States.

Viral Pneumonia

Viral pneumonia can be caused by a variety of viruses, making it a diverse category within pneumonia. Respiratory syncytial virus (RSV) is a common cause of viral pneumonia in children, while in adults, the influenza virus and SARS-CoV-2, responsible for COVID-19, are significant contributors. Even the common cold can lead to viral pneumonia.

Symptoms of viral pneumonia encompass coughing, fever, chills, shortness of breath, confusion (especially in older adults), sweating, headache, loss of appetite, chest pain, and fatigue. Viral pneumonia typically develops when individuals are exposed to droplets or aerosols from someone actively infected, leading to lung inflammation and an immune response that results in pneumonia.

In mild cases, managing symptoms through rest and adequate hydration can suffice for treating viral pneumonia. However, more severe cases often require antiviral treatments like Tamiflu (oseltamivir) or remdesivir. If symptoms persist or worsen, seeking prompt medical attention is crucial.

Certain vaccines designed to prevent other viral infections, such as influenza and COVID-19, may also reduce the risk of developing viral pneumonia as a complication of these illnesses.

Fungal Pneumonia

Fungal pneumonia primarily poses a risk to individuals with weakened immune systems, such as those who are human immunodeficiency virus (HIV)-positive and have progressed to acquired immune deficiency syndrome (AIDS). Additionally, people exposed to large quantities of specific fungi from contaminated soil or bird droppings may be susceptible to fungal pneumonia. However, for most individuals in the United States with normal immune systems, fungal pneumonia is not a significant concern, except for certain organisms.

Fungi responsible for causing pneumonia include Pneumocystis jiroveci, which leads to Pneumocystis pneumonia (PCP), as well as the Coccidioides fungus, which causes Valley fever or coccidioidomycosis. Other fungi like Histoplasma and Cryptococcus species can also lead to fungal pneumonia under specific circumstances.

Fungal pneumonia typically occurs when individuals inhale fungal spores. Healthcare providers generally treat fungal pneumonia with antifungal medications like fluconazole.

In summary, pneumonia is a prevalent respiratory infection characterized by inflammation and infection in the lungs, and it can result from various causes, including bacteria, viruses, and fungi. Recognizing the specific type of pneumonia you may have is essential for tailoring effective treatment strategies. While mild cases can often resolve with rest, adequate hydration, and symptom management, more severe cases may require targeted interventions such as specific antibiotics for bacterial pneumonia, antiviral medications for viral pneumonia, or antifungal treatments for fungal pneumonia.

In addition to targeted treatments, supportive care, including oxygen therapy and respiratory treatments, may be necessary to alleviate symptoms and facilitate recovery. Preventative measures are equally crucial in managing and preventing pneumonia. Maintaining good respiratory hygiene, such as regular handwashing and covering your mouth and nose when coughing or sneezing, can help reduce the risk of infection transmission.

Furthermore, vaccination against common pathogens that can cause pneumonia, such as the influenza virus and Streptococcus pneumoniae bacteria, is highly recommended, especially for individuals at higher risk, like the elderly and those with weakened immune systems. Prompt medical attention should always be sought if you suspect pneumonia or experience severe respiratory symptoms, as early diagnosis and treatment can significantly improve outcomes and prevent complications. Remember that your healthcare provider is the best source of guidance and care when dealing with pneumonia or any respiratory illness.