Pneumonia is a respiratory infection where the tiny air sacs in your lungs become inflamed and filled with fluid. It can range in severity from mild to life-threatening.

Although fever is a common symptom of pneumonia, in some cases you can have pneumonia without a fever.

Read on to learn more about this topic, the different types and causes of pneumonia, and symptoms to look for.

Common symptoms of pneumonia include:

Pneumonia symptoms, such as fever, may be absent or less severe in some populations, including:

  • newborns
  • infants
  • older adults

In these situations, there may be other warning signs to look out for.

Older adults or people with a compromised immune system may actually have a lower body temperature if they have pneumonia. Additionally, older adults with pneumonia may also have changes in mental state, such as confusion.

Newborns and infants may or may not have a fever, but can experience rapid breathing, nasal flaring, and grunting. Signs of a very severe infection may also include not eating, low body temperature, and convulsions.

Pneumonia can sometimes cause serious complications and become life-threatening. Potential complications can include:

People that may be at risk for more serious symptoms or complications include:

There are several types of pneumonia. They can be classified by how you get the infection.

Community-acquired pneumonia (CAP)

This is the type of pneumonia that you can get within your community and outside of a hospital or healthcare setting. It accounts for between 5 and 12 percent of lower respiratory infections in adults treated by primary care physicians.

Healthcare-acquired pneumonia

Sometimes you can get pneumonia while you’re staying in a hospital or long-term care facility. This type of pneumonia can be more serious because bacteria that are resistant to antibiotics may cause the infection.

Ventilator-associated pneumonia (VAP)

VAP occurs after being placed on a ventilator. A ventilator helps you to breathe by providing oxygen through a tube placed in your nose or throat or through a hole in your neck.

While ventilators can be very important to people who are very ill or recovering from surgery, they can also make it easier for the germs that cause pneumonia to enter the lungs.

Aspiration pneumonia

Aspiration pneumonia happens when you accidentally inhale a small bit of something like food, drink, or vomit into your lungs. This can lead to germs being introduced into your lungs.

Aspiration pneumonia is more likely to occur in:

  • people whose gag reflex has been disrupted
  • those in an altered mental state, such as through drug or alcohol use
  • those who have been vomiting frequently

Walking pneumonia

Walking pneumonia is caused by a bacterial infection. You may also see it referred to as atypical bacterial pneumonia. It’s often caused by a type of bacteria called Mycoplasma pneumoniae.

Walking pneumonia can be a milder illness. Because of this, some people may not even realize they’re sick.

Pneumonia can also be classified by the type of germ that’s causing it. These can include things like bacteria, viruses, and fungi.

Bacterial pneumonia

Bacterial pneumonia can be divided into typical and atypical types. Common typical bacteria include Streptococcus pneumoniae and Haemophilus influenzae.

Atypical bacteria can include:

Many types of bacterial pneumonia involve symptoms like high fever, sweating, and quick breathing.

People with atypical (walking) pneumonia may experience milder symptoms, such as low-grade fever, headache, and dry cough.

Viral pneumonia

Various types of viruses can cause viral pneumonia, including:

Many cases of viral pneumonia are milder than those of bacterial pneumonia. Symptoms can include fever, cough, and aches, and pains.

Fungal pneumonia

Pneumonia caused by a fungal infection is more common in people with a compromised immune system. However, people with a healthy immune system can get it as well.

The fungi that can cause these infections are often found in the soil or in bird droppings and can be caused by organisms like:

In some cases, the symptoms of fungal pneumonia may take a week or more to develop. They can include fever, cough, and chest pain.

Pneumonia is caused by several types of germs, many of which are contagious. This means that they can be spread from person to person, potentially causing pneumonia.

You can inhale these organisms through airborne droplets that are generated when someone with the germs coughs or sneezes. You can also become infected by touching contaminated objects and then touching your face or mouth.

Fungal pneumonia typically isn’t contagious. Instead, it’s acquired through inhaling spores present in the environment. However, infections due to P. jirovecii have been observed to spread between individuals.

To reduce your risk of becoming ill with pneumonia, follow the steps below.

  • Practice good hygiene. Wash your hands frequently with soap and warm water. Use an alcohol-based hand sanitizer if soap and water isn’t available.
  • Get vaccinated. Some causes of pneumonia have vaccines available. These include vaccines for pneumococcal disease, influenza, and Haemophilus influenzae type b (Hib).
  • Avoid smoking. Smoking can damage your lungs and lower their ability to fight off infections.
  • Keep your immune system healthy. This can include doing things like eating a healthy diet and getting regular exercise.

In order to diagnose pneumonia, your doctor will first take your medical history and perform a physical exam. During this exam, they may listen to your lungs for bubbling or rumbling sounds that could indicate pneumonia.

Additionally, there are several other tests that can be used to help diagnose pneumonia:

  • Chest X-ray. This checks your lungs for signs of inflammation.
  • Blood tests. These can include a complete blood count (CBC) that can let your doctor know if your body is fighting an infection. Blood testing can also check for bacteria in your blood.
  • Sputum testing. For this culture, mucus is collected from one of your deep coughs. This can help your doctor determine what’s causing your infection.
  • Pulse oximetry. This test measures the amount of oxygen in your blood using a small sensor.

In more serious cases or where complications are suspected, your doctor may perform the following additional tests.

  • Pleural fluid culture. A small sample of fluid is collected from the pleural space. This sample can then be tested for bacteria.
  • CT scan. This type of imaging technology gives more detail than an X-ray. This can help check for complications like fluid in the lungs or lung abscesses.
  • Bronchoscopy. A doctor uses a camera on a small, flexible tube to examine your airways and lungs. This can be useful to see if something is blocking your airways or to collect a fluid or tissue sample.
Is it pneumonia?

Are you feeling ill and aren’t sure what you’ve come down with? Review the questions below:

  • Do you have a persistent cough that brings up mucus?
  • When you cough or breathe deeply, do you feel discomfort in your chest?
  • Do you feel short of breath while performing normal activities?
  • Did your symptoms develop shortly after you had a viral infection such as a cold or the flu?
  • Are you currently (or were you recently) staying in a hospital or other healthcare facility?
  • Did you recently come into contact with someone that had pneumonia?
  • In addition to a cough, do you feel tired, fatigued, or have a loss of appetite?

If you’ve answered “yes” to many of these things, you could have pneumonia.

Remember, not everyone with pneumonia has fever or other common symptoms.

If you think you have pneumonia, make an appointment with your doctor to receive a diagnosis and begin treatment, especially if you’re in an at-risk group.

If you have pneumonia, treatment depends on the cause of your pneumonia as well as your overall health. Let’s review some possible treatment options below.

Prescription medications

The type of medication you’re prescribed will depend on the germ that’s causing your infection.

Antibiotics are used to treat bacterial infections while antivirals and antifungal medications are prescribed to treat viral and fungal pneumonia, respectively.

Hospitalization

Hospitalization may be required if your symptoms are very severe or if you’re in a group that’s at risk for developing complications. That way, you can receive treatment while your condition is carefully monitored.

If you’re not able to breathe well, you may be put on a ventilator. People with low blood oxygen levels may also receive oxygen therapy. If you’re hospitalized for pneumonia, you may receive your medications via IV.

At-home care

There are several things that you can do at home while you’re recovering from pneumonia:

  • Rest up. Making sure that you’re getting plenty of rest can help your body fight the infection.
  • Drink plenty of fluids. This not only helps you on your way to recovery, but can also loosen mucus in your lungs.
  • Take over-the-counter (OTC) medications. These medications may help relieve aches and pains and fever. Examples include ibuprofen (Motrin, Advil) and acetaminophen (Tylenol).
  • Use cough syrup sparingly. Coughing actually helps to loosen and clear mucus from your lungs. However, if it’s preventing you from getting rest, you can take a small dose of cough syrup.
  • Avoid areas where smoke or other irritants may be present. This can further irritate your airways and lungs while they’re healing.
  • Drink warm beverages or use a humidifier. Moist air may help open your airways and improve breathing.
  • Follow your treatment plan. Take all medications as directed by your doctor. If you’re prescribed antibiotics, make sure to take the entire course even if you begin to feel better.
When to see a doctor

Be sure to see your doctor if you’re experiencing any of the following symptoms:

  • trouble breathing
  • fever of 102°F (38°C) or higher
  • persistent cough, especially if it brings up sputum
  • chest pain

Remember that in some groups, fever and other common symptoms may be mild or even not present. You may have to watch for other warning signs like low body temperature or confusion.

The time that it takes to recover from pneumonia can vary by individual. Some may find that they can go back to their normal routine in about a week. Others may need some additional time to recover. Sometimes tiredness and fatigue can linger for several weeks.

Illness may also be more severe in at-risk groups like young children, older adults, and people with underlying conditions. These groups often require hospitalization and close monitoring through their treatment and recovery.

What about the different causes of pneumonia? The time until symptoms improve can also depend on what’s causing your infection.

In bacterial pneumonia, you may begin to feel better after several days of antibiotic treatment. Viral pneumonia typically improves in 1 to 3 weeks while fungal pneumonia may require taking antifungal medications for weeks or even months.

what to do while recovering

Remember, the germs that cause pneumonia can be contagious. While you’re recovering, be sure to do the following:

  • limit contact with others
  • cover your nose and mouth when you cough
  • wash your hands frequently
  • throw away any used tissues promptly in a covered container

Be sure to speak to your doctor about when you can go back to your normal activities. Your doctor may also want to schedule a follow-up chest X-ray to make sure that your infection has completely cleared.

While fever is a common symptom of pneumonia, it’s possible to have pneumonia without a fever. This can occur in specific groups, such as young children, older adults, and people with a weakened immune system.

Pneumonia can be caused by a variety of germs, some of which are contagious. The treatment and recovery time can be dependent on what’s causing your illness as well as on your overall health.

It’s important that pneumonia is treated promptly to prevent complications. If you suspect you have pneumonia, make an appointment with your doctor to discuss your concerns and receive a diagnosis.

If you don’t already have a provider, our Healthline FindCare tool can help you connect to physicians in your area.