DENGUE. Dengue in its initial stage or degree of progress in some respects resembles the Flu, and is often mistaken for it. Such was the case in the years 1900–1901 when imported laborers from Porto Rico, W. I. carried the Dengue or Breakbone fever with them. This disease has practically disappeared, a sporadic case of it comes to light now and then. Its transmission by the Mosquito, Culex fatigans, is not yet definitely determined. A new and more virulent type or species of the Influenza Bacillus was carried overseas to the port of Honolulu in the third week of June, 1918, and spread to the residents of the town; and it was this new imported type of Influenza that was responsible for the high mortality in the epidemics of that disease in 1918–1920, due to Influenza and complicating Pneumonia, the so-called Pulmonary or Pneumonic form of the disease. All these matters have been fully described in the public press, and in part in the Reports of the Board of Health, which q—v. CHAPTER IV. GENERAL CONSIDERATIONS. _Contents—Effect of Influenza on Man; Pulmonary Influenza or Influenza-Pneumonia; Immunity; Incubation; Salient Points; Quarantine; Cause of “Flu”; Why Microbes Created; Flu Preventatives; Hours When Flu Attacks; Salient Points._ _Effect of Influenza on Man._ When the Influenza Bacillus or Microbe has gained access to the system of man, it speedily produces an acute infectious toxaemia or blood poisoning, due to the toxin or poison liberated in the blood by the Bacillus; there are also other disease producing micro-organisms found in the sputum or spit of the Influenza victim; these are spheroid or bead shaped and called Cocci (kokkos, a berry, Greek), which apparently aid the B Influenza as allies of destruction to our systems. The effects of the “Flu” poisoning on the human lung somewhat resembles the conditions seen in those who have died from inhaling strong Chlorine gas, Carbon mon-oxide or Nitrogen gases in an atmosphere devoid of Oxygen. The type or general character of the “Flu” which has prevailed in Hawaii during the past two years, especially in Honolulu in the months of January, February, March and April, 1920, is the highest development of destructiveness to man, that the B Influenza is capable of. It was the true Russian Catarrh or Malignant “Flu,” and so called by the Italians Catarro Russo and not Influente or Influenza. This type of the “Flu” was reintroduced into the U. S. A. in the spring of 1918. INFLUENZA-PNEUMONIA. Pulmonary Influenza or Influenza-Pneumonia frequently complicates the “Flu” in some epidemics, but not in all of them; it is the main cause for the mortality due to that disease. A century and a half ago the French physicians first demonstrated its peculiarities, and its difference from ordinary Pneumonia, which is as follows: