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Influenza Pandemic

The influenza Pandemic appeared in the spring of 1918 as a three-day ailment accompanied by fever. By late summer, it seemed to have passed, but returned in the autumn as in a more virulent, deadly form. A third and final wave occurred in early 1919. Estimates of its final death toll range from 20 to 100 million worldwide.

When the flu first struck, some wondered if it were a new, biological weapon. Nations at war feared that sharing information on the flu would provide useful intelligence to the enemy. Neutral Spain was under no such constraint and reported on the influenza, leading to it being called Spanish influenza.

The second deadly wave was first recorded at Camp Devens in Massachusetts, 35 miles west of Boston. Concentrations of troops in camps, bases, troopships, cities and trenches all helped spread the flu.

The pandemic was caused by an H1N1 virus.