A lung infection occurs when a pathogen invades the lungs and begins to reproduce. This causes the immune system to trigger an inflammatory response to fight off the infection, which can lead to various unwanted symptoms.
While some lung infections can be severe and require immediate medical attention, others are mild and can resolve on their own.
In many cases, people may have a lung infection without even realizing it, as they can easily go unnoticed if you don’t know what to look for.
Therefore, in this article, we’ll explore the most common signs and symptoms that may indicate you’ve had a lung infection without knowing it.
Lung Infection Signs and Symptoms
- Persistent Cough
- Weakness and Fatigue
- Runny Nose
- Shortness of Breath
- Loss of Taste or Smell
- Chest Pain
- Body Aches
- Mucus Production
- Coarse Breath Sounds
- Hair Loss
A fever is a temporary increase in body temperature, usually above the normal range of 98.6°F (37°C) in adults. It is a common symptom of many illnesses, including infections, and is often the body’s way of fighting off an infection.
A cough is a natural reflex that helps to clear mucus and irritants from the lungs. However, if you have a persistent cough that lasts for more than a week, it could be a sign of a lung infection.
Weakness and Fatigue
Lung infections can cause weakness and fatigue, making it difficult to carry out daily activities. This can be due to the body’s immune system working to fight off the infection or due to the infection itself causing inflammation in the body.
While a runny nose is more commonly associated with upper respiratory infections, such as the common cold or flu, it can also be a symptom of a lung infection.
This is because the airways and nasal passages are connected, and an infection in the lungs can cause inflammation and mucus production in the nose and sinuses.
Shortness of Breath
Shortness of breath is a symptom characterized by a feeling of breathlessness or difficulty breathing. It can occur during a lung infection due to the buildup of mucus or secretions in the lungs.
Loss of Taste or Smell
It is thought that the loss of taste or smell during a lung infection is due to the inflammation and damage to the olfactory nerves and receptors that are responsible for these senses.
This damage can affect the ability of these nerves and receptors to detect and transmit taste and smell signals to the brain.
An infection in the thoracic region can result in stabbing chest pain that is worsened by coughing or deep breathing.
This type of pain is often localized to a specific area of the chest and may be accompanied by other symptoms, such as shortness of breath or a persistent cough.
Body aches are a common symptom of many illnesses, including lung infections. They are often caused by the body’s immune response to the infection, as the immune system produces cytokines and other chemicals that can cause inflammation and pain in the muscles and joints.
Chills are a common symptom of many infections, including lung infections, and are often accompanied by other symptoms such as fever and body aches.
Chills can be described as a feeling of coldness or shivering and are often a sign that the body is trying to fight off an infection.
Mucus production is a common symptom of lung infections, as the body tries to flush out pathogens and irritants from the respiratory system.
Mucus is a sticky substance that lines the respiratory tract and helps to trap particles and microorganisms, preventing them from reaching the lungs.
However, during a lung infection, the body may produce an excess of mucus, making it difficult to breathe.
The color and consistency of the mucus can vary depending on the type and severity of the infection. Normal mucus is clear or white in color. However, during a lung infection, it may become thicker and appear yellow, green, or brown.
Coarse Breath Sounds
Coarse breath sounds may be heard during a lung infection due to the buildup of mucus in the airways of the lungs. These sounds can be described as low-pitched, rumbling noises that are similar to snoring.
They are heard during both inspiration and expiration. The presence of coarse breath sounds is a sign that the airways are partially blocked, which can make it more difficult to breathe.
While not as common as other symptoms, hair loss can occur with severe or long-lasting lung infections. This is because the body’s immune system can attack hair follicles as it tries to fight off the infection.
A high fever, sudden loss of weight, and stressful events may lead to the shedding of hair called telogen effluvium.
In the case of a lung infection, telogen effluvium can occur for weeks or months after the infection subsides.
Cyanosis is a symptom that occurs when the skin, lips, and nails turn blue or purple in color due to a lack of oxygen in the bloodstream.
It can be caused by various factors, including lung infections, heart disease, and other respiratory or circulatory conditions. Cyanosis is a serious symptom that requires immediate medical attention.
What Does a Lung Infection Feel Like?
A lung infection can feel different depending on the type and severity of the infection, as well as the individual’s overall health and immune response. However, several common symptoms may be experienced during a lung infection.
These symptoms can vary in severity and duration and may be more pronounced in individuals with weakened immune systems or underlying health conditions.
In severe cases, a lung infection may cause complications such as pneumonia or respiratory failure, which can be life-threatening.
How to Know if You Have a Lung Infection?
The best way to know you have a lung infection is to look for the signs and symptoms. The most common is a persistent cough, which may be dry or produce mucus.
Other symptoms may include fever, fatigue, weakness, shortness of breath, chest pain, chills, body aches, mucus production, and loss of taste or smell. Coarse breath sounds or wheezing may also be heard during a lung infection.
However, the signs and symptoms of a lung infection can be similar to other conditions, so it is important to see a healthcare provider for an accurate diagnosis.
What are the Signs That You Have Pneumoinia?
Pneumonia is a lung infection caused by various microorganisms, including bacteria, viruses, and fungi.
It’s a serious condition that can range from mild to severe and can be life-threatening, especially in individuals with weakened immune systems or underlying health conditions.
Pneumonia causes various signs and symptoms, including a persistent cough, shortness of breath, fever, fatigue, chest pain, chills, mucus production, and unexplained weakness or malaise.
How Long Can You Have Pneumonia Without Knowing?
The length of time a person can have pneumonia without knowing can vary depending on the type and severity of the infection, as well as the individual’s overall health and immune response.
Therefore, a person may have pneumonia for several days or even weeks before they begin to experience symptoms.
It’s important to note that pneumonia is a serious condition that can become life-threatening if left untreated.
In some cases, the symptoms of pneumonia may be mild or may be mistaken for other respiratory conditions, which can delay diagnosis and treatment.
How Can You Get a Lung Infection?
There are several ways that a person can get a lung infection, including inhalation of respiratory droplets, contact with contaminated surfaces, or having a weakened immune system.
It is important to practice good hygiene, such as frequent hand washing and covering the mouth and nose when coughing or sneezing, to help prevent the spread of respiratory infections.
Additionally, avoiding exposure to environmental irritants and harmful substances, as well as quitting smoking, can help reduce the risk of developing a lung infection.
What is Mucus That Forms in the Bronchial Tubes During a Respiratory Infection?
During a respiratory infection, the body produces mucus in the bronchial tubes as a defense mechanism to trap and remove pathogens such as viruses, bacteria, and irritants.
Mucus is a thick, sticky substance that lines the respiratory tract, and it helps to moisten and protect the airways.
The mucus that forms in the bronchial tubes during a respiratory infection is typically thicker and stickier than normal, and it can be more difficult to cough up. This can cause symptoms such as coughing and shortness of breath.
The color and consistency of the mucus may also vary depending on the type and severity of the infection.
Treatment for excessive mucus production may include drinking plenty of fluids, using a humidifier or steam inhalation to help loosen the mucus, and taking medications such as expectorants or decongestants to help thin the mucus and make it easier to cough up.
When to See a Doctor
If you have any concerns about your symptoms or suspect that you may have a lung infection, it’s important to see a healthcare provider as soon as possible.
Early diagnosis and treatment can help to prevent complications and promote a faster recovery.
A lung infection can go unnoticed for days, weeks, or even months, and the symptoms can be mild or mistaken for other respiratory conditions.
However, it is important to pay attention to any signs or symptoms, such as persistent cough, shortness of breath, fever, chest pain, and fatigue, and seek medical attention if these symptoms persist or worsen.
Early diagnosis and treatment can help prevent complications and promote a faster recovery.
By practicing good hygiene, avoiding exposure to environmental irritants and harmful substances, and quitting smoking, you can reduce the risk of developing a lung infection and maintain healthy lungs.
John Landry, BS, RRT
John Landry is a registered respiratory therapist from Memphis, TN, and has a bachelor's degree in kinesiology. He enjoys using evidence-based research to help others breathe easier and live a healthier life.
- Harvard Health. (2019, April 22). Telogen Effluvium.
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