He died of cholera on nov 6th, 1893 a few days after the premiere of his Symphonie Pathetique, said after drinking some contaminated water. But cholera infestation was less likely or less severe in cold countries,particularly during winter(just my guess). He definitely was not poor that his living environment was unhygenic. AIDS seems to have earlier origin than once thought. Could it be that Tchaikovsky was weakened by AIDS and subsequently died of cholera?
"Genetic studies of the virus suggested in 2008 that the most recent common ancestor of the HIV-1 M group dates back to the Belgian Congo city of Léopoldville (modern Kinshasa), circa 1910"
"Later research established these theories were mostly correct: HIV-1 groups M and O started to spread in humans in late 19th–early 20th century.."
