Worn with pain, and weak from the prolonged hardships which I had undergone, I was removed, with a great train of wounded sufferers, to the base hospital at Peshawur. Here I rallied, and had already improved so far as to be able to walk about the wards, and even to bask a little upon the verandah, when I was struck down by enteric fever, that curse of our Indian possessions. For months my life was despaired of, and when at last I came to myself and became convalescent, I was so weak and emaciated that a medical board determined that not a day should be lost in sending me back to England. I was dispatched, accordingly, in the troopship Orontes, and landed a month later on Portsmouth jetty, with my health irretrievably ruined, but with permission from a paternal government to spend the next nine months in attempting to improve it.
November 26, 1890: Holmes took to his bed. [DYIN]
I was horrified, for I had heard nothing of his illness. I need not say that I rushed for my coat and my hat. As we drove back I asked for the details.
‘There is little I can tell you, sir. He has been working at a case down at Rotherhithe in an alley near the river and he has brought this illness back with him. He took to his bed on Wednesday afternoon and has never moved since. For these three days neither food nor drink have passed his lips.’
Source: A Day by Day Chronology of Mr. Sherlock Holmes according to Zeisler and Christ, compiled by William S Dorn, BSI, DWNP.