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ate at work. Cases of measles or acute catarrh in a country .district do not affect many persons, but it is otherwise in a camp; for here there are opportunities for cross-infection which do not exist in civil life, especially in the country. The miningococcus introduced by a carrier into groups of catarrh-infected persons is likely to find conditions favourable to the development of its virulent attributes, and this doubtless is what often may happen in camp life. Men from the country are perhaps more likely to form small coteries associating closely together, and the individuals forming the coteries are not: protected against measles and other catarrhal infectious by preliminary attacks as are men from the towns. A meningoeoccus-catrier in such a group becomes, therefore, a very serious danger. We see then a reasonable explanation for the various features of the epidemic—the tendency for meningococcal infection to appear in camps; the greater prevalence among men from the country; the infection of small territorial groups; and the appearance after some weeks in camp, during which period the preliminary catarrhs are being contracted and spread. The prevalence in the winter months is a sequel to the epidemics of these preliminary catarrhs, and to the colder weather driving the men into crowded overheated buildings. The absence of disease among men from Wellington City and neighbourhood is probably a result of these men having their homes and friends to go to while on leave. There is less temptation for them to form those social groupings during which opportunities for close contact arise. We see clearly also that the elimination of the carrier is only one of the precautions to aim at. We must also seek to prevent the crowding-together of recruits, more especially during their moments of leisure, till they have obtained in a measure the immunity enjoyed by town dwellers. But perhaps most important of all must be the efforts to minimize the preliminary infections, both as to spread and as to virulence. We have had in the first four months of the present year but 42 eases of measles, as against 55!) in the same time last year. Influenza has also been conspicuously less—l3s cases as against 928 last year. How fat this is due to systematic gargling and inhalation, which is now enforced in the camps, it is not possible to say with certainty, but it probably has played a large part. In any case the results so far have been that we have had but I case of meningococcal infection in the two camps, as against 5 in 1916. which is encouraging. The full value of the recent precautions, however, will not be put to the test till the camps have been subjected to the influence of the wot, cold months of June and July, Yet with the increased knowledge we have gained of this disease, with the segregation at Tauherenikau of newly arrived Reinforcements for a month apart from the rest of the troops, with the increased facilities for bacteriological examination and for spraying and isolating contacts, and with the new hospital wards wherein patients can be carefully classified, we may hope to find a lessening in the number and severity of the attacks during the coming winter. R. H. Makgill, Lieut.-Colonel, Assistant Director Medical Services (Sanitary).

Ip/voxiimUe Cost of Paper. —Preparation, not given; printing (600 copies), £10

Uy Authority : Makcus P. Marks, Government Printer, Wellington.—1917

Price !J,i.]