2/25/99
Microbiology II
C. botulinum and C. tetani
· P 686-689
· C. tetani
· Transmitted by through same route as C. perfringes
· Wound, deep, dirty, dead tissue (deeper than 1cm will leave dead tissue)
· Tetanus
· Almost any object that is sharp, dirty/clean can transmit the organism
· May carry endospores that are the transmission vehicle (anaerobic conditions)
· Spores can remain dormant for some time
· May germinate and produce 2 toxins
1. Tetanespasmin—2nd most deadly toxin produced by any system; may be released w/I days from the wound; it may be locked up in an abscess and is released wks later; transmitted through nerve route; reaches nerve endings—synaptosomes
2. tetanolysin—not involved in tetanus
· Symptoms
· 1st affects muscles of the jaw—Lock jaw
· generalized muscle spasm
· painful situation that arises
· very painful death
· person dies as a result of the spasm of the respiratory muscles
· disease has been kept under control by preventative methods
· once symptoms begin, it becomes more difficult to save the life
· Tx: keep patient in dark room and reduce activity
· sedatives to make less painful
· tracheotomy—facilitate respiration
· nasogastric feeding
· immunoglobulins—specially prepared to tetanus toxin—artificial passive immunization
· should be administered as quickly as possible
· prevention by artificial active immunization—vaccine
· DPT—tetanus toxoid—given early in childhood and several boosters
· Gives immunity for a given amount of time (5 yrs, 10 yrs)
· Obligate anaerobe
· Part of normal flora of horses, cattle and 25% of humans
· Fecal transmission
· Annual cases is below 100 since1975
· More in elderly women
· Neurotoxin—not known to leave any residual damage if have 100% recovery
· Tetanus neonatorum—contaminated knives are used to cut umbilical cord after the baby is delivered and mud is smeared on the cut end
· Structure—double shaped organism—spore deforms
· Very resistant; can survive in dust
C. botulinum
· Botulism
· 6 serotypes
· in US A, B, and E are most common
· rod, spore forming, gram negative
· botulus means sausage
· food borne, infant botulism, and wound botulism
· food is 90% of cases, toxin is heat sensitive
· improperly canned foods (nonacid)—green beans, green pepper
· food not cooked and eaten w/toxin will get sick
· toxin is more resistant to heat than any other toxin (100`C for 10 minutes)
· resistant to freezing
· botulism toxin is the #1 deadliest in toxicity, not heat stable
· most potent toxin known (compared to Shigella and tetanus )
· 0.000005microgram can kill a mouse
· disease botulism is not an infection
· the live organism is not needed
· it is a toxemia
· symptoms appear 8 – 36 hours after ingestion
· earliest symptoms are bulba paralysis (difficulty in swallowing); immediately after is generalized paresis, nystagmus (rhythmic movement of eyeball), dilopia (
· do not lose senses but there is nothing the patient can do for themselves
· artificial passive immunization; should be administered as soon as possible
· mixture of ABE serotypes
· trachetomy to aide breathing
· saline enemas—
· earlier symptoms appear, the more deadly the disease it going to be
· not only the ones that have shown the symptoms, but everyone who ate together should be considered potential victims
· prompt treatment is important to save a life
· polyvalent anti-toxin is started immediately
· antibiotics is of no use
· mortality rate is <10% w/treatment
· complete recovery w/time
· no vaccine available
· fig 24.8
Infant botulism
· 1976
· 30-100 cases/yr
· in California
· associated w/feeding honey to infants
· C. spores in honey
· “floppy baby” syndrome
· under 6 months and rarely after 12 mon
· good prognosis and death is rare
· have to be hospitalized
Wound Botulism
· 1 case/yr
· deep crushing wound
· endospores in blood and goes to body
· junctions b/w nerves and muscles
· progressive paralysis
· mortality rate is 25%