What is Pneumonia?

By Dr. Magdy Badran

CAIRO, Feb. 15 (SEE) - Pneumonia is a common lung infection that may be caused by bacteria, viruses, or fungi. The lungs are made up of small sacs called alveoli, which fill with air when a healthy person breathes.

When an inpidual has pneumonia, the alveoli are filled with pus and fluid, which makes breathing painful and limits oxygen intake.

Pneumonia is the single largest infectious cause of death in children worldwide. It accounts for about 1.6 million deaths a year in this age group -18% of all deaths among children under five.

More than 99% of all pneumonia deaths occur in low-and-middle-income countries. South Asia and sub-Saharan Africa bear the burden of more than half of the total number of cases of pneumonia among children under five worldwide.

Streptococcus Pneumonia is the most common cause of bacterial pneumonia in children. Haemophilus influenza type b is the second most common cause of bacterial pneumonia.

Viral pneumonia is caused by a virus and is the most common cause of pneumonia in children under age 5. Viral pneumonia is the leading cause of hospitalization of infants. It is usually not as serious as bacterial pneumonia.

Most people with viral pneumonia recover within one to three weeks without treatment, though some cases become severe and require hospitalization. Examples of viruses that can cause viral pneumonia include Influenza viruses, Respiratory syntactical virus, Human parainfluenza viruses, and Rhinovirus.

The respiratory syncytial virus is the most common cause of viral pneumonia in infants under a year old and the second most common viral cause of pneumonia in adults. It can cause pneumonia in any age group and can be especially severe in adults over 65 and in people whose immune systems are compromised.

Influenza is the most common cause of pneumonia, especially among younger children, the elderly, pregnant women, or those with certain chronic health conditions. Influenza results in between 250 000 and 500 000 deaths every year around the world.

Fungal pneumonia is rare and more commonly occurs in people with compromised immune systems or chronic health problems.

Hospital-acquired pneumonia or nosocomial pneumonia refers to any pneumonia contracted by a patient in a hospital at least 48–72 hours after being admitted. It can be serious because the bacteria causing pneumonia can be resistant to antibiotics.

Common symptoms of pneumonia include cough, difficulty breathing, rapid heartbeat, fever, feeling generally unwell, sweating and shivering, loss of appetite and chest pain– which gets worse when breathing or coughing.

Pneumonia can be spread in a number of ways. The viruses and bacteria that are commonly found in a child's nose or throat can infect the lungs if they are inhaled. They may also spread via airborne droplets from a cough or sneeze.

Risk factors for pneumonia include malnutrition or undernourishment, indoor air pollution , living in crowded homes, a weakened immune response; such as caused by age-related immune senescence, immunosuppressive medications, HIV infection, smoking, colds, chronic obstructive pulmonary disease, asthma, diabetes, cardiovascular disease, liver disease, drug or alcohol abuse, chronic kidney disease, cancer and overuse of antibiotics resulting in antimicrobial resistance.

Not all cases of pneumonia are caused by transmissible organisms. For example, aspiration pneumonia can occur when someone inhales an unwanted substance, like vomit, into their lungs.

Possible pneumonia complications include sepsis, septic shock, lung abscesses, lung abscesses, respiratory failure, kidney failure, and heart failure.

Antibiotics can be effective for many of the bacteria that cause pneumonia. For viral causes of pneumonia, antibiotics are ineffective and should not be used.

Antibiotic resistance is growing amongst the bacteria that cause pneumonia. This often arises from the overuse and misuse of antibiotics in and out of the hospital. There are few or no treatments for most viral causes of pneumonia.

Pneumonia can be prevented by immunization, adequate nutrition, managing ongoing medical conditions like asthma and by addressing environmental factors.

Vaccines are available for some but not many causes of pneumonia. The influenza vaccine is effective for those strains circulating that year, so it should be taken again every year. The pneumococcal pneumonia vaccines are recommended for those in higher-risk groups.

Immunization against Haemophilus influenza type b, pneumococcus, measles, and whooping cough is the most effective way to prevent pneumonia.

Preventing pneumonia in children is an essential component of a strategy to reduce child mortality. Adequate nutrition improves children's natural defenses, starting with exclusive breastfeeding for the first 6 months of life. In addition to being effective in preventing pneumonia, it also helps to reduce the length of the illness if a child does become ill.

Addressing environmental factors such as indoor air pollution, cleaning surfaces that are touched a lot and encouraging good hygiene in crowded homes also reduces the number of children who fall ill with pneumonia. Regular handwashing with soap has been shown to reduce the risk of pneumonia by 25%.