50506
He was promoted to lieutenant on 21 April 1905 and then spent the next two years in Tibet and Sikkim before moving to Benares in 1907 where he caught diphtheria .
 Tibet, Sikkim, Benares, diphtheria
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: media, plant, vehicle, astronomical object, time, disease, animal, location, person, organization, mythical figure, food, biology, geographical phenomenon, instrument, event 
Text: {0} 
Answer:
 Tibet, Sikkim, Benares, diphtheria