how to get pneumonia

You develop pneumonia when germs—most commonly bacteria or viruses —enter your lungs and cause the tiny air sacs (alveoli) to swell and fill with fluid or pus. While anyone can get pneumonia, it frequently develops as a secondary complication after another respiratory illness, such as the flu or a cold.¹²³⁴

Common Ways People Contract Pneumonia

• Breathing in airborne droplets. Contagious bacteria and viruses spread through the air when an infected person coughs, sneezes, or talks nearby.¹
• Touching contaminated surfaces. You can pick up respiratory germs by touching an object with germs on it and then touching your mouth or nose.¹
• Developing a secondary infection. Having a viral illness like the flu, COVID-19, or RSV weakens your respiratory defenses, making it easier for bacteria to multiply in your lungs.¹²
• Inhaling food, liquid, or saliva. Known as aspiration pneumonia, this happens when foreign substances accidentally go down your windpipe instead of your food pipe. This is more common if you have a swallowing problem, brain injury, or impaired gag reflex.¹²
• Inhaling environmental fungi. Less commonly, people with weakened immune systems contract fungal pneumonia by breathing in spores found in soil or bird droppings.¹²

Main Types of Pneumonia by Source

According to medical guidelines from the NHS and the Mayo Clinic, doctors classify pneumonia based on the germ and where it was acquired:

• Bacterial pneumonia. Often caused by Streptococcus pneumoniae, this type can occur on its own or after a cold or flu. A milder form caused by Mycoplasma pneumoniae is often called "walking pneumonia".
• Viral pneumonia. Triggered by viruses such as influenza, RSV, or SARS-CoV-2 (COVID-19), this form is usually milder than bacterial pneumonia.
• Hospital-acquired pneumonia. Caught during a hospital stay for another illness, this type can be more serious because the bacteria may be resistant to standard antibiotics.¹²³

Factors That Increase Your Risk

Certain health conditions and habits make it harder for your lungs to clear out germs:¹²

• Age. Infants under age 2 and adults over age 65 face a significantly higher risk.
• Chronic health conditions. Ongoing lung diseases (like asthma or COPD), heart disease, and diabetes make your lungs more vulnerable.
• Weakened immune system. People undergoing chemotherapy, taking immunosuppressants, or living with HIV/AIDS have a harder time fighting off lung infections.
• Smoking and substance use. Smoking damages your lungs' natural defenses against respiratory infections, while excessive alcohol or drug use increases the risk of aspiration.¹²³⁴⁵⁶

Note: Contrary to common myths, going outside in cold or wet weather does not directly cause pneumonia. Only germs or inhaled substances cause the infection, though cold temperatures can temporarily lower your body's immune response. ¹For more details on symptoms and prevention, visit the CDC Pneumonia Overview or consult a healthcare professional if you are experiencing persistent coughing, fever, or difficulty breathing.¹²

Pneumonia itself is not a single contagious "bug"—rather, it is an infection that inflames the air sacs in one or both of your lungs. While you don't "catch" pneumonia as a package deal, you catch or develop the underlying germs and conditions that trigger it.¹

How the Infection Spreads

• Viruses and Bacteria (Contagious): The most common culprits are viruses (such as influenza, RSV, or COVID-19) and bacteria (like Streptococcus pneumoniae). These germs spread from person to person through tiny airborne droplets when someone coughs, sneezes, or talks, or by touching a contaminated surface and then your face.¹²
• Complication from a Mild Illness: You can develop pneumonia as a secondary infection. For instance, a standard cold, the flu, or COVID-19 can start in your upper respiratory tract and eventually travel down into your lungs, turning into pneumonia.¹²
• Fungi (Not Contagious): You can breathe in fungal spores from the soil or bird droppings. Fungal pneumonia is rare in healthy people and doesn't spread between humans.¹²
• Aspiration (Non-Contagious): You can get aspiration pneumonia if you accidentally inhale food, drink, vomit, or saliva into your lungs, introducing foreign bacteria that spark an infection.¹

Common Risk Factors

Not everyone who catches a cold or encounters bacteria gets pneumonia. Your risk increases if you:

• Are an infant or a young child, or are over the age of 65.
• Have a weakened immune system (due to illness, medications, or chemotherapy).
• Smoke or vape, which damages your lungs' natural defenses.
• Have chronic underlying health conditions like asthma, COPD, heart disease, or diabetes.
• Recently recovered from—or are currently fighting off—flu, RSV, or COVID-19.¹

Prevention

• Vaccination: Stay up to date on vaccines that protect against major pneumonia triggers, including the pneumococcal vaccine, flu shot, COVID-19 boosters, and RSV vaccines (if you're eligible). You can check local guidance via the NHS Pneumonia Overview or consult your GP.
• Good Hygiene: Wash your hands frequently with soap and water, and avoid close contact with people who have active respiratory infections.
• Support Your Lungs: Avoid smoking and manage chronic health conditions closely with your healthcare provider.

If you are experiencing symptoms like a persistent cough, fever, chills, or difficulty breathing, contact a doctor or use local healthcare services (such as calling 111 in the UK or visiting a local clinic) for an evaluation.

Pneumonia is an infection that causes inflammation in the lungs. It can make it difficult to breathe and can sometimes be life-threatening.

How do people get pneumonia?

Pneumonia can develop through:

• Bacterial infections – often caused by bacteria such as Streptococcus pneumoniae.
• Viral infections – including flu, COVID-19 and RSV.
• Fungal infections – less common, usually affecting people with weakened immune systems.
• Aspiration – when food, liquid or vomit accidentally enters the lungs.

What increases the risk?

• Having flu or another respiratory infection.
• Smoking or vaping.
• Having a weakened immune system.
• Certain underlying lung conditions.

Symptoms of pneumonia

• Coughing (sometimes with mucus).
• Fever and chills.
• Chest pain when breathing.
• Shortness of breath.
• Feeling extremely tired.

Can I ask why you're wondering how to get pneumonia?

Are you:

1. Just curious about how someone catches it?
2. Worried you might have pneumonia?
3. Trying to make yourself ill or deliberately get pneumonia?

You can be honest with me. I'm not here to judge you. ❤️