Tetanus
Unlike the other vaccine preventable diseases, tetanus is not communicable person to person. Tetanus (“lockjaw”) is caused by a potent neurotoxin produced by the anaerobic bacterium Clostridium tetani. The bacterium is a ubiquitous organism found in soil and the intestines of animals and humans. The organism multiplies in wounds—particularly dirty wounds with devitalized tissues—elaborating a plasmid-encoded exotoxin that binds to skeletal muscle and to neuronal membranes without causing an inflammatory response.
Generalized tetanus, the most common form of disease, usually begins with spasms of the face and chewing muscles causing trismus—or as it is popularly called “lockjaw”—causing a characteristic facial expression, the risus sardonicus or sardonic grin. As the illness progresses, trismus is often accompanied by intense muscle spasms.
In the late 1890s it was recognized that passive prophylaxis with equine antiserum could prevent tetanus. This, plus aggressive surgery, was the only means to combat tetanus in World War I. Chemical inactivation of tetanus toxin in the early1920s permitted the active immunization with tetanus toxoid to prevent tetanus by the US Army in World War II. The prophylactic use of vaccine plus post-injury management (a booster dose of tetanus toxoid, aggressive surgery, and passive prophylaxis with antiserum) dramatically reduced the occurrence—and therefore the mortality—of tetanus among the US Army in World War II compared to WWI.
Neonatal tetanus—generalized tetanus in newborn infants—occurs in infants whose mothers are not immune because they have not received vaccine. Because of nearly universal immunization with tetanus toxoid, neonatal tetanus is now rare in the USA but remains an important cause of neonatal mortality in developing countries.
In the late 1940s, routine tetanus toxoid immunization of children started in the USA. There has been a steady decline in cases from about 500 to 600 cases a year to the all-time low in 2009 of 18 cases—that is, from 0.4 cases/100,000 population to 0.01cases/100,000 population. Mortality because of better wound care and the use of human tetanus immunoglobulin (which has now replaced horse antiserum) has decreased from 30% to 10%. Persons who recover from tetanus still need to be immunized against tetanus, however, as immunity is not acquired after tetanus. That is, so-called natural immunity to tetanus does not occur.
Almost all cases of human tetanus that occur in the USA now occur in adults who have either not been immunized or have not had a booster dose within 10 years.
http://immunizationinfo.com/
Unlike the other vaccine preventable diseases, tetanus is not communicable person to person. Tetanus (“lockjaw”) is caused by a potent neurotoxin produced by the anaerobic bacterium Clostridium tetani. The bacterium is a ubiquitous organism found in soil and the intestines of animals and humans. The organism multiplies in wounds—particularly dirty wounds with devitalized tissues—elaborating a plasmid-encoded exotoxin that binds to skeletal muscle and to neuronal membranes without causing an inflammatory response.
Generalized tetanus, the most common form of disease, usually begins with spasms of the face and chewing muscles causing trismus—or as it is popularly called “lockjaw”—causing a characteristic facial expression, the risus sardonicus or sardonic grin. As the illness progresses, trismus is often accompanied by intense muscle spasms.
In the late 1890s it was recognized that passive prophylaxis with equine antiserum could prevent tetanus. This, plus aggressive surgery, was the only means to combat tetanus in World War I. Chemical inactivation of tetanus toxin in the early1920s permitted the active immunization with tetanus toxoid to prevent tetanus by the US Army in World War II. The prophylactic use of vaccine plus post-injury management (a booster dose of tetanus toxoid, aggressive surgery, and passive prophylaxis with antiserum) dramatically reduced the occurrence—and therefore the mortality—of tetanus among the US Army in World War II compared to WWI.
Neonatal tetanus—generalized tetanus in newborn infants—occurs in infants whose mothers are not immune because they have not received vaccine. Because of nearly universal immunization with tetanus toxoid, neonatal tetanus is now rare in the USA but remains an important cause of neonatal mortality in developing countries.
In the late 1940s, routine tetanus toxoid immunization of children started in the USA. There has been a steady decline in cases from about 500 to 600 cases a year to the all-time low in 2009 of 18 cases—that is, from 0.4 cases/100,000 population to 0.01cases/100,000 population. Mortality because of better wound care and the use of human tetanus immunoglobulin (which has now replaced horse antiserum) has decreased from 30% to 10%. Persons who recover from tetanus still need to be immunized against tetanus, however, as immunity is not acquired after tetanus. That is, so-called natural immunity to tetanus does not occur.
Almost all cases of human tetanus that occur in the USA now occur in adults who have either not been immunized or have not had a booster dose within 10 years.
http://immunizationinfo.com/
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