This article discusses a method that has been recently developed that allows the direct quantitative enumeration of the fecal‐coliform‐organism group by the membrane filter (MF) technique without the need for prior enrichment or subsequent chemical testing. A medium for fecal coliform organisms (MFC) is recommended that contains no inhibitory substances for coliform bacteria and that depends on an incubation temperature of 44.5°C for 24 hrs. for its selectivity.
Summary A study has been made of coli‐aerogenes bacteria isolated from 251 soil samples collected from 26 States and 3 foreign countries. Based on land use, the soils were classified in 8 classes of the undisturbed group and one additional group of soils which were known to have been exposed to various kinds of faecal pollution. Faecal coli‐aerogenes organisms were usually absent, or present in comparatively small numbers only, in undisturbed soils, with most counts being less than 1.8/g. There was a marked increase in the numbers in soils of the polluted group, with a density of between 3,300 and 49,000/g. Intermediate types represented 76% of the 2,348 strains isolated from the undisturbed soil classes, as contrasted with only 17% of 665 polluted soil strains. The IMViC reactions of the predominant type from the undisturbed group were ‐ + ‐ +, and this type represented 48% of the 2,348 strains isolated. The sanitary significance of the ‐ + ‐ + intermediate type as a soil coli‐aerogenes organism, in relation to data on types from faecal samples and certain remote mountain streams, suggests that the strains giving these IMViC reactions, and which are 45° negative, may possibly be considered as a type characteristic in unpolluted soils but relatively infrequent where faecal pollution has occurred. Since soil contains high numbers of organisms, other than coli‐aerogenes bacteria, which frequently produce false positive reactions by the ‘confirmed test’ procedure, the ‘completed test’ method is recommended for the examination of soils for coli‐aerogenes organisms.
Potable water must be provided for drinking and culinary purposes on vessels operated in interstate traffic. In ports of the United States and its possessions, potable water may be obtained only from water supplies and at watering points approved by the Sur¬ geon General of the Public Health Service. If the water is treated aboard, the methods used must be approved by the Surgeon General. Many vessels sailing to foreign ports, particularly those carrying a large number of passengers, do not have sufficient potablewater tank capacity or distilling units to meet the demands, and water from foreign ports is taken on board. These supplies are usually of a satisfactory bacteriological quality, but they may require a second disinfection. The Ameriean President Lines has been interested in the use of the ultraviolet process for disinfecting water on its ships which cruise around the world. In Febru¬ ary 1961, experimental testing of an ultraviolet process was started on the SS President Polk and continued during six around-the-world cruises. In December 1961, Dr. Rodney Yoell (deceased), chief surgeon of the Ameriean President Lines, requested the Surgeon General to evaluate the process under actual operating conditions. One of the authors of the following paper, C. B. Huff, performed engineering and bacteriological tests aboard the President Polk when she sailed from San Francisco via Asian and European ports to New
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