Answer:
At the time, pandemic influenza was new to the world and only people exposed to milder forms of influenza in earlier flu seasons (usually winter) had partial protection against this more virulent form of the virus. And since it happened in the pre-antibiotic era, heavily infected patients were likely to die from viral pneumonia and complicating bacterial infections.
The pandemic started in January 1918, overlapping with the war for nine months and persisting in its aftermath as people travelled back to their homes. Indeed, the war played a major role in its spread and severity.
Explanation: The great influenza pandemic of 1918-19, often called the Spanish flu, caused about 50 million deaths worldwide; far more than the deaths from combat casualties in the World War One (1914-18). In fact, it may have killed between 3% and 6% of the global population.
At the time, pandemic influenza was new to the world and only people exposed to milder forms of influenza in earlier flu seasons (usually winter) had partial protection against this more virulent form of the virus. And since it happened in the pre-antibiotic era, heavily infected patients were likely to die from viral pneumonia and complicating bacterial infections.
The pandemic started in January 1918, overlapping with the war for nine months and persisting in its aftermath as people travelled back to their homes. Indeed, the war played a major role in its spread and severity.
