Good living, careful personal hygiene, fresh air in abundance, avoidance of over heated and poorly ventilated rooms, together with a general high standard of living, are excellent in their way to prevent ordinary disease; but in so far as they can prevent any one from being infected by the Flu, the absolute protection is entirely lacking in them; none of these very essential hygienic principles can produce IMMUNITY, which is the SOLE protector from an attack, or more than one attack of Influenza, and it is Nature’s standby, and by means of which it braces up the system to convalescence and ultimate recovery. Successful Vaccination against Small-pox will prevent or render mild an attack of that disease, in 95% of those who have been vaccinated and re-vaccinated. A baby in arms if successfully vaccinated is Immune and protected; whereas an unvaccinated giant living in a balmy climate, should he contract Small-pox, will probably be a candidate for a coffin or the furnace of a Crematory. A mild climate cannot alter nor render less harmful to the system of man, the specific toxin or poison of Influenza once it is liberated into his blood; nor the toxin of any other micro-organism of the infectious type. In the combat with disease, many of the advantages of our Hawaiian climate are to a certain extent neutralised by a lack of stamina and disease resistance (and also the neglecting to call in the services of a physician at an early stage of the illness) of some of our inhabitants. Any person who is affected with symptoms of disease, such as fever, headache, nasal discharge, cough, sore and tickling throat, and lassitude, during the prevalence of Flu, epidemic or sporadic, should take to bed, and by so doing, it may mean and is in line with a quick recovery, and a mild case of that disease: whereas fighting off the disease and struggling to pursue one’s daily avocation may change a mild type of illness to a very grave and hopeless one. In this respect Influenza resembles Typhoid fever of the ambulatory type, the victim does not realize how sick he is, but when the hour comes that exhausted body and brain forces him to seek his bed, it is often too late, and death or prolonged sickness awaits him. Frequently the athlete and the physically strong, when stricken with Flu, refrain from early rest, struggle against the inroads of the disease, exhaust their recuperative powers, and when finally driven to bed, collapse and die: whereas a weaker individual being speedily overcome, gives up and takes early to bed and recovers. The death rate amongst those who are attacked by the “Flu” varies in each epidemic and pandemic; as a fair average, approximately most recover, say 75%; incomplete recovery 15%; and in the late epidemic in Honolulu, the winter of 1920, the death rate was 8% to 10%; in the U. S. A. it was 4% to 6%; and in Europe 4½%. INCUBATION.