During the Thirty Years War (1618–1648), about 8 million Germans were killed by bubonic plague and typhus. The disease also played a major role in the destruction of Napoleons La Grande Armée in Russia in 1812. During the retreat from Moscow, more French military personnel died of typhus than were killed by the Russians. Of the 450,000 soldiers who crossed the Neman River on 25 June 1812, fewer than 40,000 returned. More military personnel were killed from 1500–1914 by typhus than from military action. In early 1813, Napoleon raised a new army of 500,000 to replace his Russian losses. In the campaign of that year, over 219,000 of Napoleons soldiers died of typhus.  Typhus played a major factor in the Irish Potato Famine. During World War I, typhus epidemics killed over 150,000 in Serbia. There were about 25 million infections and 3 million deaths from epidemic typhus in Russia from 1918 to 1922. Typhus also killed numerous prisoners in the Nazi concentration camps and Soviet prisoner of war camps during World War II. More than 3.5 million Nazi crimes against Soviet POWs died out of the 5.7 million in Nazi custody.
Question: Over how many years of time in Russia were there about 24 million infections and 3 million deaths from epidemic typhus?
Answer: 4