Page 197 - Encyclopedia Of World History

diseases—overview 547

from a combination of plague and warfare by the time
the Mongol empire collapsed and the Ming dynasty took
power in 1368.
Plague continued to visit all these lands at irregular
intervals thereafter.The population in Europe continued
to decline until about 1480, when the accumulated resis-
tances among survivors at last permitted population
growth to resume. Population growth accelerated once
the plague disappeared from England and northern
Europe after a final visit to London in 1665, partly be-
cause efforts at quarantining ships coming from plague-
infected ports reduced exposure and partly because slate
roofs, introduced as protection against fire, created much
greater distance between humans and hungry rat fleas
than had prevailed when rats nested overhead in the
thatch. In eastern Europe and Asia, plague continued to
break out until the twentieth century, but little by little
local adaptations reduced its impact everywhere.
Overall, the most enduring change came to the steppes
—the Mongol homelands—where nomadic herdsmen
found themselves permanently exposed to a very lethal
The search for cures for illness has been
infection. Losses were so heavy that nomads even with-
universal in the human experience over the
drew from the fertile grasslands of the Ukraine, leaving
course of history. In this photo two women
them vacant for agricultural pioneers to encroach upon,
are visiting El Santeria de Chimayo in New
beginning about 1550. This reversed a human tide that
Mexico to obtain healing earth from the
had favored nomad expansion ever since the first mil-
hole in the floor of the room.
lennium BCE, carrying first Indo-European and then Turk-
ish languages across Europe and much of Asia.
Other changes in disease patterns accompanied or the transmission of skin diseases. Needless to say, no one
soon followed the sudden expansion of bubonic plague. knows for sure.
The most conspicuous was the retreat of leprosy, empty- Ironically, another skin disease, yaws, caused by a bac-
ing thousands of leprosaria that Europeans had built to terium indistinguishable from the one that causes
isolate lepers in accordance with biblical injunctions. syphilis, may also have been nearly banished from Euro-
Many lepers died of plague during the first onset; but pean populations.The epidemic of syphilis that broke out
something else must have been at work to overcome the after 1494 may have been the result of the bacterium
various skin infections that medieval Europeans lumped finding a new path of propagation via the mucous mem-
together and called leprosy. One possibility is Europe’s branes of the sex organs. Again, no one can be sure.
reduced population had a proportionally larger supply of Yet all the mingling and transformations of diseases
wool with which to clothe themselves, and by wearing across Eurasia and Africa before 1500 never erased local
long, warm nightclothes and thereby reducing skin-to- differences. Above all, large parts of the earth remained
skin contact between people, they may have cut down on unaffected by the rising tide of infection among Old