Pneumococcus
Pneumococcus, scientifically known as Streptococcus pneumoniae, is a spherical bacterium commonly found in the upper respiratory tract, particularly among young children. It can be highly infectious and is transmitted through respiratory droplets. While there are over ninety strains of pneumococci, only a select few are responsible for severe illnesses, including pneumonia, sepsis, and meningitis. Non-invasive pneumococcal diseases, such as bronchitis and otitis media, generally cause milder symptoms and can often be managed at home. However, invasive infections are more serious and can lead to life-threatening conditions, particularly affecting those under two years of age, adults over sixty-five, and individuals with weakened immune systems.
Pneumonia, the most common invasive pneumococcal disease, affects hundreds of thousands of Americans annually, with a notable percentage resulting in fatalities. Sepsis and meningitis, while less frequent, carry higher mortality rates and require urgent medical attention and antibiotics. Vaccination plays a crucial role in prevention, with several vaccines available, including the pneumococcal conjugate vaccine (PCV13) and the polysaccharide vaccine (PPSV23), both targeted at high-risk populations. Understanding pneumococcus and its associated diseases is essential for recognizing and addressing potential health risks.
On this Page
Pneumococcus
Pneumococcus (plural pneumococci), also known as Streptococcus pneumoniae, is a highly infectious bacterial microorganism that can cause a number of serious illnesses, some of which can be life-threatening. The bacterium is most commonly found in the human respiratory tract and can be transmitted from person to person through droplets dispersed in the air. More than ninety strains of pneumococcal bacteria exist, but only a few produce the most serious illnesses, such as pneumonia, sepsis, and meningitis.
Overview
Pneumococcus is a spherical-shaped bacterium usually found in the upper respiratory tract, especially among young children. The bacterium's scientific name is Streptococcus pneumoniae, from the Greek words strepto, meaning "twisted," and coccus, meaning "berry." The term pneumoniae refers to the bacterium's tendency to attack the lungs and cause pneumonia.
More than ninety types of pneumococci exist, most of which cause non-invasive infections. These occur outside major organs or the bloodstream and are usually less serious. Invasive infections occur within major organs or the bloodstream, places that are usually free from bacteria. These are more serious illnesses and can be fatal at times.
Pneumococcal diseases occur most often in children under the age of two, adults over sixty-five, and people whose immune systems have been weakened by other diseases or medical conditions or by smoking. These illnesses are responsible for more deaths worldwide than any other infectious disease.
Common non-invasive pneumococcal diseases include bronchitis, an infection of the bronchial tubes in the lungs; otitis media, a middle-ear infection and a common cause of earaches in children; and sinusitis, an infection in the cavities near the nasal passages. Symptoms of these infections are usually mild and can be treated with rest, fluids, and over-the-counter medicines.
The more serious invasive infections affect the lungs, the bloodstream, or the membranes surrounding the brain and spinal cord. The most common of these is pneumonia, an infection of the lungs. The Centers for Disease Control and Prevention in the United States estimated in 2012 that about nine hundred thousand Americans contract pneumonia each year and that 5 to 7 percent of those cases are fatal.
Blood infections include the less serious bacteraemia and a potentially life-threatening form of blood poisoning called sepsis or septicemia. A pneumococcal infection that affects the lining of the brain or spinal cord is meningitis. While these forms of infection are less common than pneumonia, they can be far more deadly. According to a 2013 report from the Cold Spring Laboratory in New York, about 20 percent of patients who contract sepsis die; that number jumps to 30 percent for patients with meningitis. Pneumococcal blood infections and meningitis occur more often in adults. They can be treated with bacteria-killing antibiotics and may require hospitalization.
Several vaccines are available to prevent pneumococcal infection. In the United States, these include the pneumococcal conjugate vaccine (PCV13 or Prevnar 13), which is recommended for infants, children under five, and adults older than sixty-five. The pneumococcal polysaccharide vaccine (PPSV23 or Pneumovax) is recommended for adults over sixty-five, children older than two who may be at high risk of disease, and adults who smoke cigarettes or have asthma.
Bibliography
"Definition of Pneumococcus (Streptococcus pneumoniae)." MedicineNet.com, www.medicinenet.com/script/main/art.asp?articlekey=4957. Accessed 4 Oct. 2016.
"Fast Facts." Centers for Disease Control and Prevention, 10 June 2015, www.cdc.gov/pneumococcal/about/facts.html. Accessed 4 Oct. 2016.
Henriques-Normark, Birgitta, and Elaine I. Tuomanen. "The Pneumococcus: Epidemiology, Microbiology, and Pathogenesis." Cold Spring Harbor Perspectives in Medicine, 2013, perspectivesinmedicine.cshlp.org/content/3/7/a010215.full. Accessed 4 Oct. 2016.
"Meningitis." Mayo Clinic, 12 Jan. 2016, www.mayoclinic.org/diseases-conditions/meningitis/home/ovc-20169520. Accessed 5 Oct. 2016.
"Pneumonia." Mayo Clinic, 21 June 2016, www.mayoclinic.org/diseases-conditions/pneumonia/home/ovc-20204676. Accessed 5 Oct. 2016.
"Pneumococcal Infections." National Health Service of the United Kingdom, 19 Aug. 2014, www.nhs.uk/conditions/Pneumococcal-infections/Pages/Introduction.aspx. Accessed 4 Oct. 2016.
"Pneumococcal Vaccination." Centers for Disease Control and Prevention, 10 Dec. 2015, www.cdc.gov/pneumococcal/vaccination.html. Accessed 5 Oct. 2016.
"Sepsis." Mayo Clinic, 15 Jan. 2016, www.mayoclinic.org/diseases-conditions/sepsis/home/ovc-20169784. Accessed 5 Oct. 2016.