Vac ci na tions
Vac ci na tions
VAC CI NA TIONS
Year of Dis cov ery: 1798
What Is It? Hu mans can be pro tected from dis ease by in ject ing them with mild
forms of the very dis ease they are try ing to avoid.
Who Dis cov ered It? Lady Mary Wortley Montagu and Ed ward Jen ner
Why Is This One of the 100 Great est?
Why Is This One of the 100 Great est?
Have you had small pox? Po lio? Ty phoid? Prob a bly not.
How ever, such in fec tious dis eases used to plague hu man kind. The word plague co mes
from one of these killer dis eases—the bu bonic plague. Through out the four teenth and fif -
teenth cen tu ries, the plague killed nearly half of the pop u la tion of Europe.
Small pox killed over 100,000 peo ple a year for a cen tury and left mil lions hor ri bly
scarred and dis fig ured. The in flu enza ep i demic of 1918 killed 25 mil lion world wide. Po lio
killed thou sands in the early twen ti eth cen tury and left mil lions paralyzed.
One sim ple dis cov ery not only stopped the spread of each of these dis eases, it vir tu ally
erad i cated them. That dis cov ery was vac ci na tions. Vac ci na tions have saved mil lions of
lives and have pre vented un imag in able amounts of mis ery and suf fer ing. Amer i can chil -
dren are now reg u larly vac ci nated for as many as 15 diseases.
How Were Vac ci na tions Dis cov ered?
How Were Vac ci na tions Dis cov ered?
Twenty-four-year-old Lady Mary Wortley Montagu, a well-known Eng lish poet, trav -
eled to Tur key with her hus band in 1712 when he be came the Brit ish am bas sa dor. Lady
Mary no ticed that na tive pop u la tions in Tur key didn’t suf fered from small pox, the dread
dis ease that had left her scarred and pock marked and that killed tens of thou sands in
England each year.
She soon learned that el derly tribal women per formed what was called “in graft ing.”
Pre vi ous Brit ish trav el ers had dis missed the prac tice as a mean ing less tribal rit ual. Lady
Mary sus pected that this an nual event held the se cret to their im mu nity from smallpox.
Vil lage fam i lies would de cide if any one in the fam ily should have small pox that year.
An old woman ar rived car ry ing a nut shell full of in fected liq uid. She would open one of the
vol un teer’s veins with a nee dle dipped in the liq uid, as the fam ily sang and chanted. The in -
fected per son stayed in bed for two to three days with a mild fe ver and a slight rash. He or
she was then as well as be fore, never get ting a se ri ous case of small pox. Mary won dered if
Eng lish pop u la tions could be protected by ingrafting.
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Upon her re turn to Eng land in 1713, Lady Mary lec tured about the po ten tial of in graft -
ing. She was dis missed as an un trained and “silly” woman. In early 1714 Caro line, Prin cess
of Wales, heard one of Lady Mary’s talks and ap proved Lady Mary’s in graft ing of con victs
and orphans.
Lady Mary col lected the puss from small pox blis ters of sick pa tients and in jected small
amounts of the deadly liq uid into her test sub jects. The death rate of those she in oc u lated
was less than one-third that of the gen eral pub lic, and five times as many of her sub jects got
mild, non-scar ring cases.
How ever, there was a prob lem with in graft ing. In oc u la tions with live small pox vi ruses
were dan ger ous. Some pa tients died from the in jec tions that were sup posed to protect them.
En ter Ed ward Jen ner, a young Eng lish sur geon, in 1794. Liv ing in a ru ral com mu nity,
Jen ner no ticed that milk maids al most never got small pox. How ever, vir tu ally all milk maids
did get cow pox, a dis ease that caused mild blis ter ing on their hands. Jen ner the o rized that
cow pox must be in the same fam ily as small pox and that get ting mild cow pox was like in -
graft ing and made a per son immune to the deadly smallpox.
He tested his the ory by in ject ing 20 chil dren with liq uid taken from the blis ters of a
milk maid with cow pox. Each in fected child got cow pox. Pain ful blis ters formed on their
hands and arms, last ing sev eral days.
Two months later, Jen ner in jected live small pox into each of his test chil dren. If Jen -
ner’s the ory was wrong, many of these chil dren would die. How ever, none of his test chil -
dren showed any sign of small pox.
Jen ner in vented the word “vac ci na tion” to de scribe his pro cess when he an nounced his
re sults in 1798. Vacca is the Latin word for cow; vac cinia is Latin for cowpox.
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