LENGTH OF QUARANTINE.—The bac teriological researches of recent years have given us some very definite informa tion bearing on this point. It has al ready been noted that the bacilli may persist in the throat for weeks after an attack, and that such bacilli have beeia proved fully virulent. Park reports a series of careful observations upon the time of the disappearance of the bacilli from the throat in 1736 cases of diph theria. Briefly, he found that the bacilli had disappeared within I week in 3 per cent. of the cases, in 1/3 of the cases at the end of the second week, in 2/3 at the end of the third week, in 4/5 at the end of the fourth week-, and in the remainder the bacilli persisted for varying periods up to 91 days. This last case was one of simple nasal discharge containing diph , theria bacilli, from which both nurse and mother contracted diphtheria. The ' mildness or severity of the case gives no basis for determining the time that the bacilli may remain in the throat. The only accurate method of determining the period of quarantine is that of making cultures from the throats. Only when cultures fail to show the presence of the bacilli in the throat or nose can the case be regarded entirely devoid of danger to others. If cultures cannot be em ployed, we may elect an arbitrary period of three weeks from the disappearance of membrane for the removal of quaran tine restrictions. After that time, if the bacilli have not actually disappeared from the throat, they are but few in number and the danger of communica tion is slight.
Disinfection of the infected rooms upon the termination of the case should be thorough. The walls and ceilings are to be scrubbed with bichloride, 1 to 1000, or rubbed down carefully with bread: a simple method of removing the clinging dirt and bacteria by mechanical means. The wood-work, floor, and furniture are to be scrubbed with bichloride. The wood-work, walls, etc., are to be re painted or papered anew. Carpets, up holstery, etc., can be disinfected by steam. Clothing, linen, etc., may be boiled. Anything which cannot be disin fected by some of these means should be burned. Books and toys that children have used during their illness should be thus destroyed. Even the most careful disinfection will in some cases prove in _effective.
Apart from these measures_ with re spect to the cases already developed, much may be done to prevent the spread of diphtheria by properly caring for chil dren who may be exposed to infection. Catarrhal conditions of the nose and throat undoubtedly afford a favorable soil for the location and growth of diph theria bacilli. Enlarged tonsils and adenoid growths in the naso-pharynx fall in the same category. All such condi tions should be carefully treated.
Healthy mucous membranes are a safe guard against attacks of diphtheria.