Pneumococcal bacteria are dispersed in the air when infected people cough or sneeze.
Pneumococcal infections usually cause fever and a general feeling of illness, with other symptoms depending on which part of the body is infected.
Diagnosis may be based on symptoms or identification of the bacteria in samples of infected material.
Young children are routinely vaccinated against these infections, and vaccination is also recommended for all people 65 years of age and older and all people at high risk.
Penicillin or another antibiotic is usually effective treatment.
(See also Overview of Bacteria Overview of Bacteria Bacteria are microscopic, single-celled organisms. They are among the earliest known life forms on earth. There are thousands of different kinds of bacteria, and they live in every conceivable... read more .)
There are more than 90 types of pneumococci. However, most serious infections are caused by only a few types.
Pneumococci commonly reside in the upper respiratory tract of healthy people, their natural host, particularly during the winter and early spring. The bacteria spread to other people when they do the following:
Inhale infected droplets dispersed by sneezing or coughing
Come in close contact with an infected person
Spread is more likely among certain populations of people, such as military personnel and homeless people. Spread is also more likely to occur among self-contained groups of people, such as people who live, stay, or work in nursing homes or long-term care facilities, hospital wards, prisons, military bases, universities or schools, shelters for the homeless, or day care centers.
Certain conditions increase the risk of developing and the severity of pneumococcal infections:
Chronic illnesses (such as heart and lung disorders, diabetes Diabetes Mellitus (DM) Diabetes mellitus is a disorder in which the body does not produce enough or respond normally to insulin, causing blood sugar (glucose) levels to be abnormally high. Urination and thirst are... read more , and liver disease Overview of Liver Disease Liver disease can manifest in many different ways. Characteristic manifestations include Jaundice (a yellowish discoloration of the skin and whites of the eyes) Cholestasis (reduction or stoppage... read more )
Disorders that weaken the immune system Disorders That Can Cause Immunodeficiency Immunodeficiency disorders involve malfunction of the immune system, resulting in infections that develop and recur more frequently, are more severe, and last longer than usual. Immunodeficiency... read more , such as HIV infection Human Immunodeficiency Virus (HIV) Infection Human immunodeficiency virus (HIV) infection is a viral infection that progressively destroys certain white blood cells and can cause acquired immunodeficiency syndrome (AIDS). HIV is transmitted... read more
Drugs that suppress the immune system Some Drugs That Can Cause Immunodeficiency Immunodeficiency disorders involve malfunction of the immune system, resulting in infections that develop and recur more frequently, are more severe, and last longer than usual. Immunodeficiency... read more , such as corticosteroids or chemotherapy drugs
Residence in a long-term care facility
Aboriginal Australians, Alaskan natives, and certain groups of American Indians
Influenza Influenza (Flu) Influenza (flu) is a viral infection of the lungs and airways with one of the influenza viruses. It causes a fever, runny nose, sore throat, cough, headache, muscle aches (myalgias), and a general... read more and chronic bronchitis Chronic Obstructive Pulmonary Disease (COPD) Chronic obstructive pulmonary disease is persistent narrowing (blocking, or obstruction) of the airways occurring with emphysema, chronic obstructive bronchitis, or both disorders. Cigarette... read more may damage the lining of respiratory tract and thus make it easier for pneumococcal bacteria to cause infection.
Also, older people, even if healthy, tend to have more severe symptoms and complications when they get a pneumococcal infection.
Symptoms and Diagnosis
Symptoms of pneumococcal infections vary depending on the site of the infection.
Most pneumococcal infections occur in the
The bacteria may also spread to and through the bloodstream (called bacteremia Bacteremia Bacteremia is the presence of bacteria in the bloodstream. Bacteremia may result from ordinary activities (such as vigorous toothbrushing), dental or medical procedures, or from infections ... read more ). Infections may occur in the tissues covering the brain and spinal cord (meningitis Acute Bacterial Meningitis Acute bacterial meningitis is rapidly developing inflammation of the layers of tissue that cover the brain and spinal cord (meninges) and of the fluid-filled space between the meninges (subarachnoid... read more ) or, less often, in heart valves (endocarditis Infective Endocarditis Infective endocarditis is an infection of the lining of the heart (endocardium) and usually also of the heart valves. Infective endocarditis occurs when bacteria enter the bloodstream and travel... read more ), bones, joints, or the abdominal cavity.
Often, symptoms of pneumococcal pneumonia Overview of Pneumonia Pneumonia is an infection of the small air sacs of the lungs (alveoli) and the tissues around them. Pneumonia is one of the most common causes of death worldwide. Often, pneumonia is the final... read more begin suddenly. People have fever, chills, a general feeling of illness (malaise), shortness of breath, and a cough. The cough brings up sputum that is rust-colored.
Commonly, sharp, stabbing chest pains occur on one side. Deep breathing and coughing make the pains worse. In about 40% of people, fluid accumulates between the layers of tissue that cover the lungs (called pleural effusion Pleural Effusion Pleural effusion is the abnormal accumulation of fluid in the pleural space (the area between the two layers of the thin membrane that covers the lungs). Fluid can accumulate in the pleural... read more ). Pleural effusion may contribute to chest pain and make breathing difficult.
Chest x-rays are taken to look for signs of pneumonia. Doctors take a sample of sputum and examine it under a microscope. A sample of sputum, pus, or blood may be sent to a laboratory to grow (culture) bacteria. Pneumococcal bacteria are easily identified. They are also tested to see which antibiotics are effective (a process called susceptibility testing Testing of a Microorganism's Susceptibility and Sensitivity to Antimicrobial Drugs Infectious diseases are caused by microorganisms, such as bacteria, viruses, fungi, and parasites. Doctors suspect an infection based on the person's symptoms, physical examination results,... read more ).
People with pneumococcal meningitis Acute Bacterial Meningitis Acute bacterial meningitis is rapidly developing inflammation of the layers of tissue that cover the brain and spinal cord (meninges) and of the fluid-filled space between the meninges (subarachnoid... read more have fever, headache, and a general feeling of illness (malaise). They have a stiff neck that makes lowering the chin to the chest painful and difficult, but this problem is not always obvious early in the disease.
Unlike older children and adults, most infants with meningitis Newborns and children under 12 months of age Bacterial meningitis is a serious infection of the layers of tissue covering the brain and spinal cord (meninges). Bacterial meningitis in older infants and children usually results from bacteria... read more do not have a stiff neck. They may only be reluctant to eat and be irritable or sluggish.
Pneumococcal meningitis may lead to complications, such as
Hearing loss (in up to 50% of people)
The diagnosis of pneumococcal meningitis requires a spinal tap Spinal Tap Diagnostic procedures may be needed to confirm a diagnosis suggested by the medical history and neurologic examination. Electroencephalography (EEG) is a simple, painless procedure in which... read more (lumbar puncture) to obtain a sample of the fluid that surrounds the brain and spinal cord (cerebrospinal fluid). The sample is checked for signs of infection, such as white blood cells and bacteria.
Pneumococcal otitis media
Pneumococcal otitis media Otitis Media (Acute) Acute otitis media is a bacterial or viral infection of the middle ear. Acute otitis media often occurs in people with a cold or allergies. The infected ear is painful. Doctors examine the eardrum... read more causes ear pain and a red, bulging eardrum or pus behind the eardrum. These infections can cause
Problems with balance
Pneumococcal bacteria causes about 30 to 40% of all cases of otitis media in children. Pneumococcal otitis media commonly recurs.
The diagnosis of pneumococcal otitis media is usually based on symptoms and results of a physical examination. Cultures and other diagnostic tests are usually not done.
Pneumococcal sinusitis Sinusitis Sinusitis is inflammation of the sinuses, most commonly caused by a viral or bacterial infection or by an allergy. Some of the most common symptoms of sinusitis are pain, tenderness, nasal congestion... read more most commonly affects the sinuses located in the cheekbones (the maxillary sinuses) and the sinuses located on either side of the nasal cavity (the ethmoid sinuses). The infection causes sinus pain and pus discharged from the nose. The infection may become chronic. The infection may extend into the skull and cause complications such as the following:
Blood clot of certain major veins in the brain (such as cavernous sinus thrombosis Cavernous Sinus Thrombosis Cavernous sinus thrombosis is a very rare disorder in which a blood clot (thrombosis) forms in the cavernous sinus (a large vein at the base of the skull). Cavernous sinus thrombosis is usually... read more )
A doctor bases the diagnosis of sinusitis on the typical symptoms. A computed tomography (CT) scan is done when people have symptoms of complications or when people have chronic sinusitis.
Pneumococcal bacteremia Bacteremia Bacteremia is the presence of bacteria in the bloodstream. Bacteremia may result from ordinary activities (such as vigorous toothbrushing), dental or medical procedures, or from infections ... read more is bacteria in the bloodstream. It may be the primary infection, or it may accompany any of the other pneumococcal infections. When bacteremia occurs, it may lead to other infections, such as in the joints (infectious arthritis Infectious Arthritis Infectious arthritis is infection in the fluid and tissues of a joint usually caused by bacteria but occasionally by viruses or fungi. Bacteria, viruses, or fungi may spread through the bloodstream... read more ), the lining of the heart (endocarditis Infective Endocarditis Infective endocarditis is an infection of the lining of the heart (endocardium) and usually also of the heart valves. Infective endocarditis occurs when bacteria enter the bloodstream and travel... read more ), or the tissues covering the spinal cord and brain (meningitis).
If bacteremia is suspected, doctors usually take a sample of blood so they can try to grow (culture) the bacteria in the laboratory and identify it.
Despite antibiotic treatment, pneumococcal bacteremia often causes death, especially in older people, people who have disorders that weaken their immune system, or people who have no spleen.
Prevention of Pneumococcal Infections
Pneumococcal infections can be prevented with vaccines and, for certain people, antibiotics.
For more information, see also Pneumococcal Vaccine Pneumococcal Vaccine Pneumococcal vaccines help protect against bacterial infections caused by Streptococcus pneumoniae (pneumococci). Pneumococcal infections include ear infections, sinusitis, pneumonia, bloodstream... read more and the vaccine schedules for children and adults from the Centers for Disease Control and Prevention (CDC).
Two types of pneumococcal vaccines are available:
A conjugate vaccine (PCV13 Administration Pneumococcal vaccines help protect against bacterial infections caused by Streptococcus pneumoniae (pneumococci). Pneumococcal infections include ear infections, sinusitis, pneumonia, bloodstream... read more ) that protects against 13 types of pneumococci
A polysaccharide vaccine (PPSV23 Administration Pneumococcal vaccines help protect against bacterial infections caused by Streptococcus pneumoniae (pneumococci). Pneumococcal infections include ear infections, sinusitis, pneumonia, bloodstream... read more ) that protects against 23 types of pneumococci
The vaccine schedules vary depending on the person's age and medical conditions.
PCV13 is recommended for
All children 2 months through 6 years of age as part of the routine childhood vaccination schedule Childhood Vaccination Schedule Most doctors follow the vaccination schedule recommended by the Centers for Disease Control and Prevention (CDC—see the schedule for infants and children and the schedule for older children... read more
People aged 65 years and over who have a condition that weakens their immune system, cerebrospinal fluid leak, or cochlear implant and who have not previously received PCV13
People aged 65 years and over who do not have any of the above conditions, provided they discuss the relative risks and benefits of the vaccine with their doctor
PPSV23 is recommended for
All adults aged 65 and over
If children under 5 years old do not have a spleen or if their spleen is not functioning, they may be given antibiotics (such as penicillin) in addition to the vaccine. In such cases, antibiotics may be continued throughout childhood and into adulthood.
Treatment of Pneumococcal Infections
Penicillin (or the related drugs, ampicillin and amoxicillin) is used for most pneumococcal infections. It is usually taken by mouth but, if the infection is severe, may be given intravenously.
Pneumococci that are resistant to penicillin are becoming more common. Thus, other antibiotics, such as ceftriaxone, cefotaxime, fluoroquinolones (such as levofloxacin), vancomycin, lefamulin, or omadacycline, are often used. Vancomycin is not always effective against meningitis caused by pneumococci. Thus, people with meningitis are usually given ceftriaxone or cefotaxime, rifampin, or both, as well as vancomycin.
The following are some English-language resources that may be useful. Please note that THE MANUAL is not responsible for the content of these resources.
CDC: Pneumococcal Disease: Information about how the infection spreads, the symptoms it causes, and how to prevent it