The following is from an article by Matt Mcgowan, published in the February 13, 2014 edition of medicalxpress.com.
(Medical Xpress)—Epidemiological data integrated with climate data taken from tree-ring estimates of soil moisture levels demonstrate that drought contributed to the spread of typhus in Mexico from 1655 to 1918, according to a new study by researchers at the University of Arkansas.
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“The observed relationship between drought and typhus epidemics in colonial and modern Mexico is curious because drought has not been specifically considered a risk factor for typhus,” Burns said. “But drought, much like war and natural disasters, caused famine in poor, agricultural regions and forced impoverished refugees to move into already crowded urban areas where infrastructure and sanitary systems were insufficient.”
