Isolation of El Tor vibrio, a particular strain of the bacterium Vibrio cholerae. Gotschlich first identified this strain in 1905 at a quarantine camp on the Sinai Peninsula in El Tor, Egypt . The vibrios were found in the guts of six pilgrims returning from Mecca. Though the pilgrims failed to show ante or post mortem evidence of cholera, the vibrios isolated from the guts were agglutinable within the anti-cholera serum.