Chapter 16 study guide
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CH. 16 Plagues without Ger ms
*The Red Plague (pellagra) – a plague of corn*
- first described in Spain in 1735 as “Mal de Rosa”(the red disease).
- generally appeared first as skin rash that covered hands and feet and sketched a butterf ly p attern
across the neck.
- In early stages, the reddening of skin might be confused as due to sun burn or poison oak, but
when the skin crusted and peeled away showing the smooth and shiny skin below, it is certain.
- symptoms: flaming of skin, loss of balance, staggering gait, senseless muttering, weak and
melancho ly, tongue became reddened , burning sensation in the mouth, diarrhea. Some went insane
- Clinical symptoms : 4Ds
dermatitis (? ? ), diarrhea, dementia, death.
- pellagra is derived from Italian meaning rough skin.
- Pellagra mainly af f licted the poor also ppl who had a diet consisting mainly corn.
- Louis Sambon claimed that its vectors were bloo d sucking insects, black flies and buffalo gnats.
But neither microbe nor vector was found.
- Early 1900s, pellagra struck the American South. It was first recognize d among the insane
hospitalized in Alabama and among tenant farmers and mill workers. Many southerners
embarrassed and denied the existenc e o f it. It become epidemic in 1909 .
- Joseph Goldberger (a skillful microbe hunter) traveled throughout American South where the
number of pellagra was highest. He discovered a paradox: doctors and nurses wh o had physical
contacts with patients. But none of them have developed the disease. It appeared it was not a
contagious disease spread by direct contact.
He suggested it was due to food. The poorer ppl have no red meat in their diet. He conducted 2
experiments: a) give milk to those who are most likely to get the disease. b) the Mississippi Rankin
Prison Farm experiment.
- In 1918, Elmer V. McCollum proposed that pellagra was a contagious disease. Goldberger
car r ied out an experiment to convince it’s not contagious. He and 20 friends and his wife each ate
a capsule with skin scrapings, urine and feces from patient. And none of them developed the
-Preventing and Curing:
Eating fresh meat, milk, eggs and vegetables. These food contain PP factor (named by
Goldberger). He demonstrated these foods are inexpensive and that brewer’s yeast worked the best.
After Goldberger died in 1929 , PP factor was chemically characterized. Experiments were
car r ied out by T.D. Spies. Nicotinic acid and its amide were renamed niacin. Niacin is a water –
soluble B vitamin. It was the specific prevention of pellagra. Gre a t depression eliminated the
disease because ppl starts to grow their own vegetables.
- Pellagra didn’t happen in Mexico because they soak the corn meal in hot limewater before eating
which released the bound of niacin.
- Why does deficiency o f niacin lead to pellagra? Because withou t it food canno t be utilized as a
source of energy. Sugar was not metabolized!
-Red p lague lead to discovery of antimetabolites. Antimetabolites – drug s designed to inhibit
bacterial growth. It was used for Mycobacterium tuberculosis.
*The White Rice Plague*
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