40 Fun Facts About Streptococcus

Which group A strep disease strikes Beth March in Little Women and the boy in The Velveteen Rabbit?

Scarlet fever was a leading cause of death in children in the early 20th century, which is why it haunts so many classic stories.

Group A strep is one cause of necrotizing fasciitis, a rare infection better known by which grim nickname?

Flesh-eating disease is a misnomer: the bacteria do not eat tissue but release toxins that kill it, making it a surgical emergency.

Which entertainer died in May 1990 of toxic shock syndrome caused by a group A streptococcal infection?

Jim Henson, creator of the Muppets, was 53; his doctor said he might have been saved had he reached hospital a few hours sooner.

Streptococcus mutans, a bacterium that thrives in the mouth, is a major contributor to which common health problem?

Tooth decay sets in because the bacterium turns sucrose into acid that erodes the enamel.

Streptococcus thermophilus, a harmless cousin of the strep throat germ, is a standard starter culture for which food?

Yogurt is made by keeping warm milk for hours with this species and Lactobacillus bulgaricus, which sour and thicken it together.

Group A strep has never developed resistance to which antibiotic, still a first-choice treatment for strep throat?

Penicillin still works against every strain, whereas some have become resistant to macrolides, tetracyclines and clindamycin.

A defence system that Streptococcus pyogenes uses against invaders was adapted in 2012 into which laboratory tool?

CRISPR gene editing relies on the bacterium's Cas9 protein as programmable scissors, work that won the 2020 Nobel Prize in Chemistry.

A group A strep infection can leave a child's tongue red and bumpy, a sign doctors name after which fruit?

Strawberry tongue begins with a white coating that sheds after four or five days, leaving the swollen red surface behind.

Which symptom, typical of an ordinary cold, usually points away from strep throat when a doctor checks a sore throat?

Cough is so unusual in strep throat that its absence scores a point on the Centor criteria doctors use to decide who needs a test.

Staphylococci, the cluster-forming look-alikes of streptococci, are named after the Greek for a bunch of which fruit?

Grapes inspired the name because these bacteria pile up in bunches; the Scottish surgeon Alexander Ogston coined it after finding them in abscess pus.

Which inflammatory disease can follow untreated strep throat by a few weeks and permanently damage the heart valves?

Rheumatic fever is the immune system's doing, not the bacteria's: antibodies made against strep mistakenly attack the body's own tissue.

Which contagious skin infection of young children, known for its honey-coloured crusts, can be caused by group A strep?

Impetigo is most common between the ages of two and five and spreads easily through schools and day care.

Group B strep, carried harmlessly by many healthy women, is a leading cause of serious infection in which group?

Newborn babies can pick it up during birth, so US guidelines call for testing late in pregnancy and antibiotics during labour for carriers.

Strep throat typically brings a fever, a sore throat and which red, swollen structures at the back of the mouth?

Tonsils often carry white patches in strep throat, and the lymph nodes at the front of the neck usually swell as well.

Under the microscope, the round cells of streptococci are typically arranged in which pattern?

Chains form because each cell divides along a single axis and the daughters stay attached, like beads on a necklace.

Strep throat, which peaks in late winter and early spring, spreads between people mainly by which route?

Respiratory droplets from talking or sneezing carry the bacteria, and touching a contaminated surface and then the mouth, nose or eyes can spread them too.

Strep throat is the best-known bacterial sore throat, but most sore throats are caused by what?

Viruses are behind most sore throats; group A strep accounts for only 5–15% of them in adults, which is why doctors test before prescribing.

Strangles, a streptococcal disease named for the swollen glands that can block the airway, affects which animals?

Horses pass it on through shared troughs, brushes and tack, and a recovered animal can remain a long-term carrier.

Streptococci are gram-positive bacteria, which means they hold which colour after the Gram stain is applied?

Purple comes from crystal violet dye trapped in the thick cell wall; gram-negative bacteria lose it and are counterstained pink.

Besides pneumonia, Streptococcus pneumoniae is a leading bacterial cause of which common childhood complaint?

Middle ear infection, or otitis media, is among the milder illnesses this bacterium causes, alongside pink eye and sinusitis.

The 'strepto' in Streptococcus, a name coined in 1877, comes from an Ancient Greek word with which meaning?

Twisted was joined to kokkos, the Greek for grain, to describe how the growing cells looked under the microscope.

The 'pyogenes' in Streptococcus pyogenes comes from Greek words meaning that the bacterium forms which substance?

Pus gave the species its name because so many of its infections, from sore throats to skin sores, produce it.

In 1944, Oswald Avery's team used pneumococcus bacteria to show which molecule carries hereditary information?

DNA was a surprise: most scientists of the day believed that proteins carried genetic information.

Which 19th-century doctor cut deaths from childbed fever, often a strep infection, by making staff wash their hands?

Ignaz Semmelweis cut maternal deaths in his clinic from 18% to under 2%, yet some doctors mocked the idea that their hands were to blame.

Post-streptococcal glomerulonephritis, a delayed complication of strep infections, is an inflammation of which organs?

Kidneys become inflamed a week or more after the infection, the time the body needs to raise the antibodies involved.

Viridans streptococci take their name from the Latin for which colour, the tint that appears around their colonies?

Green gave these mouth-dwelling bacteria their name; they are mostly harmless but can infect heart valves if they reach the bloodstream.

Streptococci are classed as alpha, beta or gamma by how fully they destroy which ingredient of their growth medium?

Red blood cells are burst completely by beta types such as group A strep, leaving a clear ring around each colony.

Streptokinase, an enzyme first obtained from streptococci, is given as an emergency medicine to do what?

To dissolve clots, it switches on the body's own clot-busting system, and it is used after some heart attacks and pulmonary embolisms.

Which American microbiologist sorted streptococci into the lettered groups, such as A and B, that doctors still use?

Rebecca Lancefield's lab was nicknamed the Scotland Yard of streptococcal mysteries because she so willingly answered other scientists' questions.

Sydenham's chorea, a nervous disorder that can follow a group A strep infection, has which historical name?

St. Vitus' dance recalls the patron saint of dancers, before whose statue crowds once danced wildly on his feast day.

In the disputed diagnosis PANDAS, a strep infection is thought to trigger the sudden onset of which childhood condition?

OCD or tics appearing almost overnight after a strep infection is the proposed pattern, though the diagnosis remains controversial.

Lab workers tell staphylococci from streptococci by whether a sample fizzes in a drop of which liquid?

Hydrogen peroxide bubbles when staphylococci are added because they make the enzyme catalase, which streptococci lack.

Streptococci belong to an order of bacteria named after which substance, their main product when fermenting sugars?

Lactic acid bacteria also include Lactobacillus and Lactococcus, and the group is usually found in decomposing plants and milk products.

Group B strep's species name, agalactiae, means 'no milk' after the udder disease it causes in which animals?

Cows with the infection give less milk, and it was studied as a costly problem of dairy herds long before doctors saw it as a threat to people.

Streptococci are a leading cause of which spreading deep-skin infection, often a hot, swollen patch on the lower leg?

Cellulitis usually starts where bacteria slip in through a break in the skin, such as a graze, an insect bite or cracks between the toes.

Streptococcus suis, caught from pigs or raw pork, most often causes which illness in people, sometimes with deafness?

Meningitis is the usual form the infection takes in people, who typically catch it by handling infected carcasses with cuts on their hands.

Which Viennese surgeon, a close friend of the composer Brahms, coined the name Streptococcus in 1877?

Theodor Billroth also pioneered surgery of the digestive tract and throat, performing the first laryngectomy in 1873.

Frederick Griffith's 1928 experiment on pneumococci in mice first revealed which process of genetic change in bacteria?

Transformation showed itself when a harmless live strain turned deadly after being mixed with killed virulent bacteria.

In 1984, gut-dwelling bacteria long classed as group D streptococci were moved into which new genus?

Enterococcus became a separate genus after genetic analysis showed how different these bacteria were; its name comes from the Greek for intestine.

Which skin infection, a raised bright-red rash with a sharp edge, did Friedrich Fehleisen trace to streptococci in 1883?

Erysipelas mostly strikes the legs today, though historically the face was the more frequent site.