From the May 1st, 1901 New York Times Interview:
"One-sixth of the natives of Luzon have either been killed or have died of Dengue fever in the last two years" was the remarkable statement of Brig. General Bell, who arrived in Washington to-day direct from the Philippines, where he was in command of four departments of Southern Luzon.
'The loss of life by killing alone has been very great," continued the General, "but I think not one man has been slain except where his death served a legitimate purpose of war. It has been necessary to adopt what in other countries would be considered harsh measures, of the Filipino is tricky and crafty and has to be fought in his own way."
"One of my sentinels was beheaded within 150 yards of my HQ. His executioner was a Bolo-man, who came into camp disguised as a fruit vendor. He had his Bolo hidden in the fruit basket and with one blow cut off the sentinel's head."
The problems with General Bell's statement are:
(1) J.M. Bell wasn't on Luzon for two years. He arrived in October 1899 and left in March 1901, and returned to the US in the Summer of 1900 for several months on sick leave.
(2) J.M. Bell was a Brig General stationed in southern Luzon. There's no evidence he visited the rest of Luzon, or knew anything about Luzon except what went on in HIS department.
(3) J.M. Bell had no way of knowing the total population in Luzon in April 1899 or April 1901.
(4) The Census records disclose no drop in Luzon's native population from April 1899-April 1901.
(5) There was no epidemic of "Dengue Fever" in the US Army or among the Luzon Filipinos in 1899-1901.
(6) Bell was 63 when he gave the interview and retired in October 1901. There's no evidence he ever testified before Congress to support his "remarkable statement" or was ever questioned further on it, by anyone.
(7) Given that Bell was in charge of 1/6 the natives on Luzon, my suspicion is that the reporter simply mis-quoted him.