Corynebacterium diphtheriae are Gram-positive, nonmotile, rod-shaped bacteria that do not form spores or branch. They do not have a typical gram-postive cell wall. It consists of arabinose, galactose, disminopimelic acid, and short chain mycolic acids. In the mycolic acid, chains of 28-40 carbons are common. They are chemoorganotroph and aerobic, exhibiting a fermentative metabolism under certain conditions. They are fastidious organisms, growing slowly on even an enriched medium. They form irregular shaped, club-shaped or V-shaped arrangements in normal growth. Their arrangement resembles Chinese letters because they undergo snapping movements just after cell division.
C. diphtheriae is an infectious disease that spreads from person to person by respiratory droplets from the throat by coughing, sneezing, or even laughing. It affects the tonsils, throat, and nose and can also affect the skin. These bacteria can lead to breathing problems, heart failure, paralysis and even sometimes death.
Its early symptoms can have C. diphtheriae mistaken for a severe sore throat. Its symptoms make a low-grade fever and the lymph nodes are enlarged in the neck. The symptoms may also appear as skin lesions that may be painful, red and swollen. These symptoms usually appear within 2 to 4 days after the infection has taken place, but they can also range anywhere from 1 to 6 days. Anyone who is carrying diphtheria germs are however contagious for up to 4 weeks without any antibiotic therapy.
The tetanus-diphtheria (Td) vaccine should be given to anyone who either: did not receive a primary series of immunization against tetanus and diphtheria during childhood, or who did not receive a booster dose within the past ten years. This vaccine stimulates the body to make neutralizing antibodies against the binding component of the diphtheria exotoxin. Once this antibody binds to the exotoxin, the toxin itself can no longer bind to the receptors on the host cell membrane. This vaccine is very safe and does not usually produce any side effects. This vaccine is not a cause for diphtheria.
There are many known cases in the world dating back to as early as the 4th century B.C., when Hippocrates provided the first clinical description of diphtheria. In the 17th century it swept through Europe and became to acquire nicknames. In Spain the disease was known as “El garatillo”, which means “the strangler”, and in Italy it was known as “the gullet disease”. It reached the American colonies in the 18th century around 1735 and often killed whole families in a few weeks.
In 1883, Klebs first described the bacterium that caused diphtheria. It was later cultivated by Loeffler in 1884, which he used Koch’s postulates and identified Corynebacterium diphtheriae as the agent of the disease. Loeffler also discovered that C. diphtheriae produced a toxin, and he provided the first description of the bacterial exotoxin. It was next tested on lab animals in 1888 by Roux and Yersin. They demonstrated the presence of the toxin in the cell-free culture fluid of C. diphtheria by injecting the animals, which caused the manifestation of diphtheria.
In the 1900’s, in the United States, the disease was very common, especially in children, making it one of the leading causes of death to infants and children. In the 1920’s there were 150,000 cases and 13,000 deaths resulted from those known cases. In 1945, after immunization was introduced, there were only 19,000 cases and a decreasing number of deaths, also. In the 1970’s, 196 cases per year were reported. In the 1980’s, the cases in the United States has dropped to 24, two of the cases resulted in death, and 18 occurred in people over the age of 20 years old.
C. diphtheriae is an infectious disease that spreads from person to person by respiratory droplets from the throat by coughing, sneezing, or even laughing. It affects the tonsils, throat, and nose and can also affect the skin. These bacteria can lead to breathing problems, heart failure, paralysis and even sometimes death.
Its early symptoms can have C. diphtheriae mistaken for a severe sore throat. Its symptoms make a low-grade fever and the lymph nodes are enlarged in the neck. The symptoms may also appear as skin lesions that may be painful, red and swollen. These symptoms usually appear within 2 to 4 days after the infection has taken place, but they can also range anywhere from 1 to 6 days. Anyone who is carrying diphtheria germs are however contagious for up to 4 weeks without any antibiotic therapy.
The tetanus-diphtheria (Td) vaccine should be given to anyone who either: did not receive a primary series of immunization against tetanus and diphtheria during childhood, or who did not receive a booster dose within the past ten years. This vaccine stimulates the body to make neutralizing antibodies against the binding component of the diphtheria exotoxin. Once this antibody binds to the exotoxin, the toxin itself can no longer bind to the receptors on the host cell membrane. This vaccine is very safe and does not usually produce any side effects. This vaccine is not a cause for diphtheria.
There are many known cases in the world dating back to as early as the 4th century B.C., when Hippocrates provided the first clinical description of diphtheria. In the 17th century it swept through Europe and became to acquire nicknames. In Spain the disease was known as “El garatillo”, which means “the strangler”, and in Italy it was known as “the gullet disease”. It reached the American colonies in the 18th century around 1735 and often killed whole families in a few weeks.
In 1883, Klebs first described the bacterium that caused diphtheria. It was later cultivated by Loeffler in 1884, which he used Koch’s postulates and identified Corynebacterium diphtheriae as the agent of the disease. Loeffler also discovered that C. diphtheriae produced a toxin, and he provided the first description of the bacterial exotoxin. It was next tested on lab animals in 1888 by Roux and Yersin. They demonstrated the presence of the toxin in the cell-free culture fluid of C. diphtheria by injecting the animals, which caused the manifestation of diphtheria.
In the 1900’s, in the United States, the disease was very common, especially in children, making it one of the leading causes of death to infants and children. In the 1920’s there were 150,000 cases and 13,000 deaths resulted from those known cases. In 1945, after immunization was introduced, there were only 19,000 cases and a decreasing number of deaths, also. In the 1970’s, 196 cases per year were reported. In the 1980’s, the cases in the United States has dropped to 24, two of the cases resulted in death, and 18 occurred in people over the age of 20 years old.
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