The first person to be diagnosed with Ebola in the US ...
Lookups spiked on October 8, 2014.
The first person to be diagnosed with Ebola in the United States, Thomas Eric Duncan, died of the disease in Texas. A hospital spokesperson said, "Mr. Duncan succumbed to an insidious disease, Ebola."
When used to describe a disease, insidious means "developing so gradually as to be well established before becoming apparent." In more general contexts, it means "having a gradual and cumulative effect" or "subtle."
It comes from the Latin word meaning "cunning" or "deceitful" and is related the Latin word for "ambush."
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