A chest infection, also called a respiratory infection, occurs when a pathogen (viral, bacterial, mycobacterial, or fungal) infects the respiratory tract. This page focuses on lower respiratory tract infections, commonly referred to as lung infections.
These infections can affect different parts of the lungs:
Chest infections also trigger flare-ups of underlying lung conditions. Clinicians refer to these flare-ups as exacerbations. Infections commonly worsen conditions such as COPD, asthma, bronchiectasis, and interstitial lung disease.
Chest infections develop when microorganisms enter the lower respiratory tract and overcome the body’s normal defence mechanisms. These infections most commonly arise from viruses and bacteria, but other pathogens can also play a role, particularly in vulnerable individuals.
Viruses are the most frequent cause of chest infections, especially in otherwise healthy people. Common respiratory viruses include influenza, respiratory syncytial virus (RSV), rhinovirus, and coronaviruses. These infections often spread easily through droplets in the air and tend to cause illnesses such as bronchitis or viral pneumonia.
Bacteria commonly cause more severe chest infections, including pneumonia. Typical organisms include Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. Bacterial infections may occur on their own or follow a viral illness, which can weaken the immune response and allow bacteria to take hold.
Some chest infections result from so-called “atypical” bacteria such as Mycoplasma pneumoniae, Chlamydophila pneumoniae, and Legionella pneumophila. These infections often present with less typical symptoms and may affect younger or otherwise healthy individuals.
Fungal infections and mycobacterial infections (including tuberculosis) are less common but can occur in people with weakened immune systems or underlying lung disease. These infections often require specialised investigation and treatment.
In some cases, chest infections develop when material such as food, liquid, or stomach contents enters the lungs (aspiration). This can introduce bacteria and lead to infection, particularly in older adults or those with swallowing difficulties.
Here is a list of common pathogens:
Gram-positive bacteria
Gram-negative bacteria
Viruses
Mycobacterium
Fungal
Several factors increase the risk of developing a chest infection. These risk factors affect how well the lungs clear pathogens and how effectively the immune system responds.
Older adults and young children face a higher risk of chest infections. Ageing reduces immune efficiency, while immature immune systems in children provide less protection against respiratory pathogens.
Smoking damages the airways and impairs the lungs’ natural defence mechanisms, including mucociliary clearance. Exposure to air pollution, dust, and occupational fumes also increases susceptibility to respiratory infections.
Chronic lung diseases significantly raise the risk of chest infections. These include:
These conditions alter airway structure or function, making it easier for pathogens to colonise and cause infection.
A compromised immune system increases vulnerability to both common and opportunistic infections. This includes people:
A recent viral infection, such as influenza or a common cold, can damage the respiratory lining and create an environment where bacteria can cause secondary infection.
Recent hospital stays, especially in intensive care, increase exposure to resistant organisms. Mechanical ventilation and invasive procedures further elevate the risk of infection.
Difficulty swallowing (dysphagia), neurological conditions, or reduced consciousness increase the risk of aspiration. When food, liquid, or gastric contents enter the lungs, they can introduce bacteria and trigger infection.
Poor nutrition, reduced mobility, and alcohol misuse weaken the body’s defences and increase infection risk.
Dr Ricardo José uses a structured, evidence-based approach to investigate chest infections. He combines clinical assessment with targeted tests to identify the cause, assess severity, and guide treatment.
Dr José uses imaging to evaluate the lungs and identify patterns of infection.
Dr José identifies the causative organism through laboratory testing.
These tests help tailor treatment, especially when infections do not respond to standard therapy.
Blood tests provide information about inflammation and immune status.
Dr José requests further tests when underlying conditions contribute to infection risk.
Dr Ricardo José tailors treatment for chest infections based on the underlying cause, severity of illness, and any co-existing medical conditions. His approach combines supportive care with targeted therapy to ensure effective and personalised management.
Dr José recommends supportive measures for most patients to help relieve symptoms and support recovery.
These measures form the foundation of treatment across all types of chest infection.
Most viral chest infections resolve without specific treatment. Dr José focuses on supportive care in these cases.
In selected patients, he may prescribe antiviral therapy, particularly for higher-risk individuals or more severe infections, to reduce complications and speed recovery.
Bacterial chest infections require antibiotic therapy. Dr José selects the most appropriate antibiotic based on:
He also determines the optimal duration of treatment to ensure full resolution while minimising unnecessary antibiotic use.
Mycobacterial infections require combination antimicrobial therapy over a prolonged period.
Dr José closely monitors these patients to ensure treatment response and manage potential side effects.
Fungal chest infections require specialist antifungal therapy. Dr José selects treatment based on the specific organism and clinical context, often working within a multidisciplinary framework for complex cases.
For more severe infections or patients at higher risk, Dr José can arrange hospital admission for closer monitoring and advanced treatment. He holds admitting privileges at:
This ensures seamless access to inpatient care, including intravenous therapies, oxygen support, and specialist respiratory input.
